Creatine: a real strength gain when it is paired with training

In a network meta-analysis of 35 randomized trials in 1211 trained athletes, creatine supplements improved muscle strength by SMD 0.46 (95% CI 0.29 to 0.63), the best result among the supplements compared, though that ranking rests partly on indirect comparisons. Almost all of this evidence is about powder, and creatine monohydrate was the form in 80% of 343 published trials, while 15.5% never said which form they used. In trials of 608 postmenopausal women followed for 12 to 104 weeks, creatine added 0.82 lb (0.37 kg) of lean mass (95% CI 0.05 to 0.69, in the 338 women with that measure) and 17 lb (7.5 kg) to the leg-press maximum (2.2 to 12.8, in 111 women). The gain showed up when 5 g a day or more was combined with resistance training, and trials using 3 g a day or less without training found no measurable effect. Food supplies far less. Among 8407 Americans on a special diet, estimated dietary creatine averaged 0.82 g a day, and 69.5% fell under a 1 g threshold that the authors chose themselves.

How much is actually in it

• In US survey data, people on special diets ate about 0.8 g of creatine a day from food, and 69.5% got less than 1 g. — 8,407 NHANES 2003-2023 participants aged 1 and over on a single special diet (n = 8407) Evidence C source
  Mean dietary creatine 0.82 g/day; 69.5% below 1 g/day; range 60.4% (renal diets) to 83.3% (low-fiber diets)

What a real portion looks like

• In RCTs of postmenopausal women, creatine added 0.82 lb (0.37 kg) of lean mass and 17 lb (7.5 kg) to leg-press strength, with benefits seen at 5 g a day or more combined with resistance training. — 608 postmenopausal women, mean age about 62, 12 to 104 weeks (n = 608) Evidence A source
  Lean mass MD +0.82 lb (95% CI 0.11 to 1.5; metric: 0.37 kg, 0.05 to 0.69); leg-press 1RM MD +17 lb (4.9 to 28; metric: 7.5 kg, 2.2 to 12.8); bone density unchanged; 3 g/day or less without training no effect

What your body absorbs

• In 15 vegans and vegetarians, 7 days of creatine monohydrate at 0.3 g/kg a day raised muscle creatine by 18.8 mmol/kg but did not improve repeated sprints. — 15 healthy young adult vegans and vegetarians, 0.3 g/kg/day for 7 days (n = 15) Evidence B source
  Muscle Cr +18.8 mmol/kg, total Cr +30.8 mmol/kg, body mass +3.4 lb (1.56 kg); sprint power unchanged
• A review of nine studies found vegetarians start with lower creatine stores and supplementation often lifts muscle creatine above omnivore levels. — vegetarians, 9 studies in 11 articles Evidence C source
  Higher muscle, plasma and red cell creatine after supplementation; no effect on brain phosphocreatine
• Of 343 creatine RCTs, only 11.1% mentioned bioavailability and 15.5% did not say which form of creatine they used. — 343 RCTs of oral creatine published 1994 to 2023 Evidence C source
  Monohydrate in 80.2%; form unspecified in 15.5%; bioavailability mentioned in 11.1%; 5 trials compared formulations

What it does to your health

• A network meta-analysis of 35 trials in 1211 trained athletes ranked creatine first for muscle strength, with an SMD of 0.46. — trained athletes with at least six months of structured training, 35 RCTs (n = 1211) Evidence A source
  Strength SMD 0.46 (95% CI 0.29 to 0.63), SUCRA 82.4%
• Across 52 RCTs in athletes, creatine improved sprint, jump and repeated-sprint performance against placebo. — healthy adult athletes, 52 RCTs, at least 2 weeks Evidence A source
  Sprint SMD -0.64, jump SMD 0.33, repeated-sprint ability SMD -0.78, upper-body endurance SMD 0.43
• In 23 professional cyclists, 20 g of creatine a day during a 6-day training camp did not improve recovery, body composition or performance. — 23 professional U23 cyclists, 20 g/day for 6 days (n = 23) Evidence B source
  No group-by-time interaction for any outcome (all p > 0.05)
• Pooling 16 RCTs with 492 adults, creatine monohydrate gave a small improvement in memory, SMD 0.31, with moderate certainty. — adults aged 20.8-76.4 years, healthy and with specific diseases, 16 RCTs of creatine monohydrate (n = 492) Evidence A source
  Memory SMD 0.31 (95% CI 0.18 to 0.44); GRADE moderate
• In 15 healthy young adults kept awake for 21 hours, one high dose of creatine (0.35 g/kg) cut self-rated fatigue by about 8% against placebo. — 15 healthy subjects aged 20-28, 8 women, single dose 0.35 g/kg creatine monohydrate or placebo during 21 h sleep deprivation (n = 15) Evidence B source
  Fatigue score reduced 8 +/- 7% vs placebo at 2 and 4 a.m.
• With 20 g a day of creatine for 7 days before up to 36 hours without sleep, only one complex executive task improved, and only at 36 hours. — men, 5 g creatine monohydrate four times a day for 7 days, then 18-36 h sleep deprivation with exercise Evidence B source
  Better central executive task at 36 h only; no difference in short-term memory, reaction time, balance or mood
• In 14 healthy adults, 7 days of 20 g creatine did not prevent the drop in reaction speed and accuracy caused by a 90-minute mentally tiring task. — 14 healthy adults aged about 24, 20 g/day creatine or placebo for 7 days, crossover (n = 14) Evidence B source
  Mental fatigue still slowed visuomotor response 4.4% and cut Flanker accuracy 5.0% in both conditions; Stroop accuracy +4.9% with creatine
• A 2026 three-level meta-analysis of 63 studies with 1,489 people found creatine plus resistance training raised lean mass more than training alone, a small effect of g 0.30. — adults in trials of resistance training plus creatine vs resistance training alone (n = 1,489) Evidence A source
  Lean mass g 0.30; upper-body strength g 0.54; lower-body strength g 0.55; fat mass g -0.10 (not significant)
• A meta-analysis of 12 RCTs in adults under 50 found creatine with resistance training added 2.5 lb (1.14 kg) of lean body mass over training alone. — adults younger than 50 years doing resistance training (n = 12 trials) Evidence A source
  Lean body mass +2.5 lb (95% CI 1.5 to 3.5; metric: 1.14 kg, 0.69 to 1.59); body fat -0.88% (-1.66 to -0.11); fat mass -1.6 lb (-3 to -0.24; metric: -0.73 kg, -1.34 to -0.11)
• A meta-analysis of 23 studies in adults under 50 found creatine with training added 9.8 lb (4.43 kg) to upper-body and 25 lb (11.35 kg) to lower-body strength. — adults under 50 doing resistance training; 467 men and 49 women (n = 23 studies) Evidence A source
  Upper-body strength WMD +9.8 lb (4.43 kg); lower-body strength WMD +25 lb (11.35 kg) vs placebo; women showed no significant gains
• A meta-analysis of 12 studies with 266 adults under 50 found creatine plus resistance exercise cut body fat by 1.19 percentage points but did not change absolute fat mass. — adults younger than 50 doing resistance exercise with creatine or placebo (n = 266) Evidence A source
  Body fat -1.19 percentage points (p = 0.006); fat mass -0.4 lb (-0.18 kg) (p = 0.76, not significant)
• A preregistered meta-analysis of 12 trials in adults under 50 found creatine with resistance training lowered fat mass by 1.6 lb (0.73 kg) more than training alone. — adults younger than 50 doing resistance training (n = 12 trials) Evidence A source
  Fat mass -1.6 lb (95% CI -3 to -0.24; metric: -0.73 kg, -1.34 to -0.11); body fat -0.88 percentage points (-1.66 to -0.11); lean body mass +2.5 lb (1.5 to 3.5; metric: 1.14 kg, 0.69 to 1.59)
• A 2026 three-level meta-analysis of 63 studies with 1,489 people found creatine with resistance training did not significantly change fat mass, g -0.10. — adults in trials of resistance training plus creatine vs resistance training alone (n = 1,489) Evidence A source
  Fat mass g -0.10 (p = 0.14, not significant); body-fat percentage g -0.14; body mass g 0.12
• In a controlled trial of male lifters on a 4-day very low calorie diet, creatine 20 g a day did not change weight or fat loss and only slightly reduced the loss of fat-free mass. — male resistance trainers on a formula diet of 18 calories/kg/day for 4 days; 20 g/day creatine or placebo Evidence C source
  Similar falls in body weight and body fat; fat-free mass -1.4% with creatine vs -2.4% with placebo; nitrogen loss similar

Safety, limits and interactions

• A meta-analysis found creatine nudged serum creatinine up slightly without changing kidney filtration rate. — 21 studies reviewed, 12 pooled with 177 creatine and 263 control participants (n = 440) Evidence A source
  Serum creatinine MD 0.07 (95% CI 0.01 to 0.12); GFR no significant difference
• In the 2026 trial of a single 0.2 g/kg dose in 29 adults, creatine was well tolerated, with no reports of stomach upset or other physical side effects. — 29 healthy adults, single dose 0.2 g/kg creatine monohydrate (n = 29) Evidence B source
  No gastrointestinal distress or other adverse physical symptoms reported
• A 2020 meta-analysis of 29 studies with 951 women found no significant difference in gastrointestinal adverse events between creatine monohydrate and placebo. — female participants taking creatine monohydrate in studies that monitored adverse outcomes (n = 951) Evidence A source
  Gastrointestinal events RR 1.09 (95% CI 0.53 to 2.24); total adverse events RR 1.24 (0.51 to 2.98); no deaths or serious adverse outcomes
• In a double-blind randomized trial in 59 male soccer players, a single 10 g dose of creatine a day caused diarrhea in 55.6 percent versus 35.0 percent on placebo, while two 5 g doses did not differ from placebo. — top-level male soccer players, 28 days of creatine 2 x 5 g, 1 x 10 g, or placebo (n = 59) Evidence B source
  Diarrhea 55.6% (1 x 10 g) vs 28.6% (2 x 5 g) vs 35.0% (placebo); no difference in GI distress between 2 x 5 g and placebo
• In a randomized trial of 54 active men loading 20 g of creatine a day for 5 days, mild stomach discomfort was reported only when creatine was combined with caffeine. — physically active males, creatine 5 g four times a day alone or with caffeine or coffee, or placebo, 5 days (n = 54) Evidence B source
  4 participants with mild GI discomfort in creatine + caffeine group; no side effects in other groups
• A Cochrane review of 14 randomized trials with 364 people with muscle diseases found no trial reported any clinically relevant adverse event from creatine. — people with muscular dystrophies, metabolic myopathies and inflammatory myopathies in RCTs of creatine (n = 364) Evidence A source
  No clinically relevant adverse events in any trial
• In a 2025 analysis of 685 creatine trials, muscle cramping or pain affected 0.52% of 12,839 people on creatine and 0.07% of 13,452 on placebo, a difference that was not statistically significant. — participants of 685 human clinical trials of creatine (mostly creatine monohydrate, about 12.5 g/day for about 65 days) and 652 placebo arms (n = 26291) Evidence A source
  Participants with cramping/pain: creatine 67/12,839 (0.52%) vs placebo 9/13,452 (0.07%), p = 0.085; studies reporting cramping/pain: 20/685 (2.9%) vs 6/652 (0.9%), p = 0.008
• A 2009 systematic review of 10 randomized trials found no evidence that creatine impairs heat tolerance or body fluid balance in athletes exercising in the heat. — athletes in randomized clinical trials of creatine and thermoregulation or hydration (n = 10 RCTs) Evidence A source
  No adverse effects on heat dissipation or fluid balance at recommended doses; PEDro scores 7 to 10
• A 2019 meta-analysis of creatine trials concluded that creatine did not cause kidney damage at the doses and durations studied. — participants of creatine supplementation studies with renal outcomes; 15 studies reviewed, 6 pooled (n = 15 studies) Evidence A source
  No renal damage at studied amounts and durations
• A 2025 meta-analysis of creatine trials found no significant change in kidney filtration rate with creatine compared with control. — people taking creatine supplements vs placebo or control; 5 studies with 69 creatine and 74 control participants in the GFR analysis (n = 143) Evidence A source
  GFR: no statistically significant difference vs control; serum creatinine MD 0.07 (95% CI 0.01 to 0.12) in 12 studies
• A 2019 systematic review of 15 studies, 6 of them pooled, concluded that creatine did not cause kidney damage at the doses and durations tested. — studies of creatine supplementation reporting serum creatinine and urea (n = 15 studies (6 in meta-analysis)) Evidence A source
  Serum creatinine SMD 0.48 (95% CI 0.24 to 0.73); urea SMD 1.10 (0.34 to 1.85)
• In a 3-month randomized trial of 18 healthy young men, about 10 g of creatine a day caused no kidney dysfunction measured by cystatin C. — healthy sedentary males 18-35 years, moderate aerobic training, 3 months (n = 18) Evidence B source
  Cystatin C fell in both groups (CR 0.82 to 0.71 mg/L; placebo 0.88 to 0.75); no between-group differences
• A 2009 systematic review of 10 randomized trials found no evidence that creatine harms heat tolerance or fluid balance in athletes. — athletes exercising in the heat; randomized clinical trials of creatine (n = 10 studies) Evidence A source
  No adverse effect on thermoregulation or body fluid balance at recommended dosages
• A 2025 meta-analysis found creatine is linked to a modest, transient rise in serum creatinine, which the authors put down to metabolic turnover rather than kidney damage. — studies of creatine supplementation reporting kidney outcomes; 177 creatine and 263 control participants in the creatinine analysis (n = 440) Evidence C source
  Serum creatinine MD 0.07 (95% CI 0.01 to 0.12); no significant difference in GFR
• In a crossover RCT of 20 rugby players, creatine loading raised DHT, a hormone linked to hair loss, by 56% after 7 days. — college-aged male rugby players; 25 g/day creatine for 7 days then 5 g/day for 14 days (n = 20) Evidence B source
  DHT +56% after 7 days, +40% after 21 days; DHT:T ratio +36%; testosterone unchanged
• A dose-response meta-analysis of 61 trials found creatine with lifting raised body weight by 2 lb (0.89 kg) and had no significant effect on fat mass or BMI. — trained and untrained adults doing resistance training with creatine or placebo (n = 61 trials) Evidence A source
  Body mass WMD +2 lb (95% CI 1.7 to 2.2; metric: 0.89 kg, 0.76 to 1.01); fat-free mass +3.1 lb (2.4 to 3.7; metric: 1.39 kg, 1.07 to 1.70); no significant effect on fat mass, BMI or body-fat percentage
• In an RCT of 63 adults, a 7-day creatine wash-in at 5 g a day added 1.1 lb (0.51 kg) of lean body mass before any training, a gain the authors tie to body water. — 34 women and 29 men, mean age 31; 5 g/day creatine monohydrate or no supplement for 13 weeks (n = 63) Evidence B source
  Lean body mass +1.1 lb (0.51 kg) vs control after 7 days; no between-group difference after 12 weeks of training
• A 2025 meta-analysis found creatine raises serum creatinine slightly, MD 0.07, without a significant change in kidney filtration rate. — studies of creatine supplementation reporting kidney outcomes; 177 creatine and 263 control participants in the creatinine analysis (n = 440) Evidence C source
  Serum creatinine MD 0.07 (95% CI 0.01 to 0.12); rise significant only in the first week; no significant change in GFR

What people believe that the data does not support

• Pooling 8 placebo-controlled RCTs, creatine did not lower CRP or IL-6, against claims that it is anti-inflammatory. — 8 RCTs in healthy people, athletes and clinical groups Evidence A source
  Chronic CRP SMD -0.11 (95% CI -0.69 to 0.48); IL-6 SMD -0.06 (-0.64 to 0.53); moderate certainty
• A review of 10 controlled trials found no sign that creatine harms heat tolerance or body fluid balance in athletes. — 10 randomized trials, athletes exercising in heat Evidence A source
  No adverse effects on thermoregulation or hydration
• The EU did not authorize claims that creatine improves mental attentiveness, concentration or mental performance. — EU health claims register Evidence E source
  Status non-authorized
• The EU did not authorize the claim that creatine enhances physical working capacity at the fatigue threshold. — EU health claims register Evidence E source
  Status non-authorized
• The EU did not authorize the claim that creatine improves mental attentiveness in the elderly. — EU health claims register Evidence E source
  Status non-authorized
• The EU authorizes a creatine claim only for physical performance in repeated short bursts of high intensity exercise, with no gut claim either way. — EU Register of nutrition and health claims, claim POL-HC-6365 Evidence E source
  Authorized
• The 2017 ISSN position stand says well-controlled studies show creatine does not raise the incidence of muscle cramping, dehydration or injury. — healthy and clinical populations taking creatine at recommended doses Evidence E source
  No increase in musculoskeletal injuries, dehydration, muscle cramping or GI upset in controlled studies
• The same ISSN review concludes that experimental and clinical research does not support the idea that creatine causes dehydration and muscle cramping. — athletes and patients in experimental and clinical studies Evidence E source
  No support for creatine causing dehydration or muscle cramping
• A 2008 review notes that an American College of Sports Medicine statement from 2000 advised people exercising intensely or in the heat to avoid creatine, a position later evidence did not support. — athletes exercising in hot environments or managing weight Evidence E source
  ACSM 2000 advised avoiding creatine; later trials suggest no added risk in the heat
• An ISSN expert review says the case reports of kidney problems on creatine were confounded by medicines, existing kidney disease, other supplements, very high doses or steroids. — published case reports of renal dysfunction during creatine use Evidence E source
  Case reports confounded; no adverse kidney effects at recommended doses in healthy people
• The same ISSN review concludes that creatine at recommended doses does not cause kidney damage or dysfunction in healthy people. — healthy individuals at recommended creatine doses Evidence E source
  No kidney damage or renal dysfunction at recommended dosages
• The ISSN position stand says well-controlled trials do not show that creatine causes cramps, dehydration, gut upset or kidney damage. — healthy people and athletes using creatine monohydrate Evidence E source
  No consistent pattern of adverse events; refutes claims of injuries, dehydration, cramping, GI upset and renal dysfunction
• The EU allows creatine products to say that daily creatine can enhance the effect of resistance training on muscle strength in adults over 55. — foods and supplements sold in the EU; adults over 55 Evidence E source
  Claim status: authorized
• An expert review in the ISSN journal says a creatine loading phase of 20 g a day for 5 to 7 days usually adds 2.2 to 6.6 lb (1 to 3 kg) of body weight, mostly water. — people starting creatine with a loading phase Evidence E source
  Body mass +2.2 to 6.6 lb (1 to 3 kg) during loading, mostly body water
• The same ISSN expert review concludes that creatine does not increase fat mass across a variety of populations. — young and older adults, athletes, postmenopausal women and patient groups in creatine trials Evidence E source
  No increase in fat mass
• The ISSN position stand says weight gain is the only side effect of creatine that has been consistently reported. — healthy people and patient groups using creatine monohydrate Evidence E source
  Weight gain is the only consistently reported side effect

Who this works differently for

• In 29 studies with 951 women, creatine did not raise total adverse events, gut complaints or weight gain. — 951 female participants in 29 studies monitoring adverse outcomes (n = 951) Evidence A source
  Total adverse events RR 1.24 (95% CI 0.51 to 2.98); GI events RR 1.09 (0.53 to 2.24); no deaths or serious events
• In a meta-analysis of 8 RCTs in healthy people, creatine improved memory in adults aged 66 to 76, SMD 0.88, but not in people aged 11 to 31. — healthy individuals in placebo-controlled RCTs, older adults 66-76 years vs younger 11-31 years (n = 8 trials) Evidence A source
  Older SMD 0.88 (95% CI 0.22 to 1.55), I2 83%; younger SMD 0.03 (95% CI -0.14 to 0.20)
• In 29 healthy adults kept awake for 21 hours, a lower single dose of creatine (0.2 g/kg) reduced the decline in cognitive tests by up to 12%. — 29 healthy subjects, single dose 0.2 g/kg creatine monohydrate or placebo during 21 h sleep deprivation (n = 29) Evidence B source
  Up to 12% less deterioration; smaller than with 0.35 g/kg
• In 22 rested young adults, 6 weeks of creatine did not change any of seven cognitive tests compared with placebo. — 22 young adults aged about 21, 0.03 g/kg/day creatine or placebo for 6 weeks, not sleep deprived (n = 22) Evidence B source
  No group, time or interaction effects on reaction time, memory, reasoning or math processing (all p>0.05)
• In a pilot RCT of 15 long COVID patients, 8 g creatine plus glucose daily for 8 weeks reduced reported difficulty concentrating, with an effect size of 0.80. — 15 adults with long COVID and moderate fatigue, 8 g/day creatine monohydrate with or without 3 g glucose vs placebo for 8 weeks (n = 15) Evidence B source
  Difficulties concentrating effect size 0.80 in creatine-glucose group (p<=0.05); body aches 1.33, headache 1.12
• Across 29 studies with 951 women taking creatine, no study reported a significant difference in measures of kidney or liver function. — 951 female participants in 29 studies of creatine monohydrate that monitored adverse outcomes (n = 951) Evidence A source
  No significant difference in renal or hepatic function; no deaths or serious adverse outcomes
• In a 2-year randomized trial of 60 older people with Parkinson disease taking 4 g of creatine a day, creatine was well tolerated and the main side effects were gastrointestinal complaints. — aged patients with Parkinson disease, creatine 4 g/day (n = 40) or placebo (n = 20) for 2 years (n = 60) Evidence B source
  Well tolerated; main side effects gastrointestinal complaints (type and rate not given in abstract); kidney markers normal
• A 2026 meta-analysis of 7 randomized trials with 608 postmenopausal women found creatine adverse events were mild and similar to placebo. — postmenopausal women aged about 62, creatine with or without resistance training, 12 to 104 weeks (n = 608) Evidence A source
  Adverse events mild and similar to placebo; renal indices unchanged
• Over one football season, 38 college players who chose to take creatine had significantly fewer cramps than 34 teammates who did not, in hot and humid conditions. — 72 NCAA Division IA football players, 38 volunteers on creatine 0.3 g/kg/day for 5 days then about 0.03 g/kg/day; mean 81 °F (27 °C), 54% humidity (n = 72) Evidence C source
  Less cramping in creatine users (chi2 = 5.35, P = .021); also less heat illness or dehydration (P = .043) and fewer total injuries (P < .001)
• Across three college football seasons, players on about 5 g of creatine a day accounted for 39% of cramps, in line with the 34 to 56% of players who used creatine. — NCAA Division IA football players, 1998 to 2000 seasons, open-label creatine 15.75 g/day for 5 days then about 5 g/day (n = 3 seasons) Evidence C source
  Cramping 37/96 (39%) in creatine users, proportional to a 34-56% use rate; total injuries 205/529 (39%)
• In a double-blind RCT of 10 people on hemodialysis with frequent cramps, creatine before each session for 4 weeks cut cramp frequency by 60%, and the benefit vanished after stopping. — 10 hemodialysis patients with frequent muscle cramps; creatine monohydrate or placebo before each session for 4 weeks (n = 10) Evidence B source
  Cramps 6.2 ± 0.8 vs 2.6 ± 1.8 times per 4 weeks (P < 0.05); back to 6.6 ± 1.1 in washout; serum creatinine rose from 10.7 to 12.4 mg/dl
• A 2024 systematic review of 13 trials of drugs and supplements for dialysis cramps rated the creatine trial among the only ones at low risk of bias. — patients on dialysis with muscle cramps in experimental studies of 9 interventions (n = 13 studies) Evidence B source
  Creatine monohydrate and L-carnitine trials the only ones at low risk of bias; vitamins C and E most studied with positive results
• A Cochrane review of 14 trials in muscle diseases found creatine well tolerated, but high-dose creatine increased muscle pain and worsened daily activities in McArdle disease. — 364 participants with muscular dystrophies, inflammatory myopathies or metabolic myopathies (n = 364) Evidence A source
  No clinically relevant adverse events in dystrophies; in McArdle disease worse activities of daily living (MD 0.54 on a 1-10 scale, 95% CI 0.14 to 0.93) and more muscle pain at high dose
• A 2020 meta-analysis of 29 studies with 951 women found no more adverse events, gastrointestinal events or weight gain with creatine than without it. — female participants in creatine monohydrate studies that monitored adverse outcomes (n = 951) Evidence A source
  Total adverse events RR 1.24 (95% CI 0.51 to 2.98); gastrointestinal events RR 1.09 (0.53 to 2.24); no serious adverse outcomes
• The ISSN position stand notes that some have suggested people with existing kidney disease consult a physician before taking creatine, as a precaution, while finding no compelling evidence of harm to kidney function. — individuals with pre-existing renal disease Evidence E source
  Precautionary physician consultation; no compelling evidence of harm to renal function
• A 2020 meta-analysis of 29 studies in 951 women found no difference in adverse events or in measures of kidney function with creatine. — female participants in creatine monohydrate trials that monitored adverse outcomes (n = 951) Evidence A source
  Total adverse events RR 1.24 (95% CI 0.51 to 2.98); no significant difference in renal function measures
• In a randomized trial of 29 older patients with peripheral artery disease, 8 weeks of creatine (20 g a day for a week, then 5 g) did not change creatinine clearance. — patients with symptomatic peripheral arterial disease, both genders; creatine 20 g/day 1 week then 5 g/day 7 weeks (n = 29) Evidence B source
  Creatinine clearance CR 108 to 117 vs placebo 88 to 82 mL/min/1.73 m2, P = 0.366
• A 17-year-old developed acute kidney injury with cast nephropathy after a 6-day high-dose creatine loading regimen, without rhabdomyolysis. — 17-year-old male athlete, 6-day high-dose creatine loading (n = 1) Evidence D source
  Acute kidney injury with cast nephropathy confirmed on biopsy; bilateral flank pain
• A dose-response meta-analysis of 61 trials found creatine with lifting added 3.1 lb (1.39 kg) of fat-free mass, in both novice and experienced lifters. — trained and untrained adults doing resistance training with creatine or placebo (n = 61 trials) Evidence A source
  Fat-free mass WMD +3.1 lb (95% CI 2.4 to 3.7; metric: 1.39 kg, 1.07 to 1.70); body mass +2 lb (1.7 to 2.2; metric: 0.89 kg, 0.76 to 1.01); trained 1.82 vs untrained 2.7 lb (1.23 kg), difference not significant
• In postmenopausal women, a meta-analysis pooling 5 RCTs with 338 women found creatine added 0.82 lb (0.37 kg) of lean mass. — postmenopausal women, mean age about 62 years; 12 to 104 weeks (n = 338) Evidence A source
  Lean mass MD +0.82 lb (95% CI 0.11 to 1.5; metric: 0.37 kg, 0.05 to 0.69); leg-press 1RM +17 lb (7.5 kg); no effect at 3 g/day or less without training
• In older adults and people with chronic disease, a meta-analysis of 33 RCTs found creatine added 2.4 lb (1.08 kg) of lean tissue, with low quality evidence. — older adults and adults with chronic disease at risk of functional disability (n = 1,076) Evidence A source
  Lean tissue mass MD +2.4 lb (95% CI 1.7 to 3; metric: 1.08 kg, 0.77 to 1.38); sit-to-stand SMD 0.51 (0.01 to 1.00)
• In a 12-month RCT of 38 men aged 49 to 69 doing supervised lifting, creatine did not add muscle thickness, lean tissue or strength over placebo. — older males, creatine 0.1 g/kg/day (n 18) or placebo (n 20) with supervised whole-body resistance training (n = 38) Evidence B source
  Similar changes in lean tissue, muscle thickness and strength in both groups after 12 months
• A meta-analysis of 29 studies in 951 women found no significant difference in total adverse events, gut complaints or weight gain with creatine. — female participants in creatine monohydrate studies that monitored adverse outcomes (n = 951) Evidence C source
  Total adverse events RR 1.24 (95% CI 0.51 to 2.98); weight gain MD 2.7 to 3 lb (1.24 to 1.37 kg), not significant
• In adults 50 and over, a meta-analysis of 19 studies with 609 people found creatine with resistance training lowered body fat by 0.55 percentage points, while fat mass loss of 1.1 lb (0.50 kg) was not significant. — adults aged 50 and over in resistance training trials of 7 to 52 weeks (n = 609) Evidence A source
  Body fat MD -0.55 percentage points (95% CI -1.08 to -0.03); fat mass MD -1.1 lb (-2.5 to 0.33; metric: -0.50 kg, -1.15 to 0.15); body mass +1.9 lb (-0.71 to 4.5; metric: 0.86 kg, -0.32 to 2.05), not significant
• A meta-analysis of 35 RCTs with 1,192 people found creatine taken without exercise did not change lean body mass, MD 0.07 lb (0.03 kg). — healthy adults in creatine RCTs, with and without exercise training (n = 1,192) Evidence A source
  Lean body mass without exercise MD 0.07 lb (95% CI -1.4 to 1.5; metric: 0.03 kg, -0.65 to 0.70); with resistance training MD 2.4 lb (1.2 to 3.6; metric: 1.10 kg, 0.56 to 1.65)
• In a 12-week RCT of 64 adults aged 45 to 65, creatine 10 g a day during an exercise and weight-loss diet program gave a greater fall in body-fat percentage and more lean tissue than placebo. — 64 sedentary adults aged 45 to 65 (40 women), mean weight 186 lb (84.5 kg); 2 x 5 g/day creatine monohydrate or placebo (n = 64) Evidence B source
  Greater reduction in body-fat percentage and higher lean tissue mass with creatine in the diet and exercise arm

What is still unknown

• Of six studies on creatine and cognition in 1542 older adults, five reported benefits, but only two were trials and only one rated good quality. — 1542 adults aged 55 and over, 2 RCTs and 4 cross-sectional studies (n = 1542) Evidence C source
  5 of 6 studies positive (memory, attention); quality: 1 good, 2 fair, 3 poor
• A systematic review found creatine raises brain creatine only modestly and its effects on cognition are equivocal. — studies of creatine supplementation and cognition Evidence C source
  Brain creatine up to a limited extent; cognition results equivocal
• The same meta-analysis of 16 RCTs found no improvement in overall cognitive function or executive function, and rated that evidence low certainty. — adults in 16 RCTs of creatine monohydrate (n = 492) Evidence A source
  Overall cognition and executive function not significantly improved; GRADE low
• A Cochrane review found no randomized trials of creatine in pregnant women, so its safety in pregnancy is untested. — pregnant women, trials of creatine for fetal neuroprotection (n = 0 trials) Evidence A source
  No completed or ongoing RCTs identified
• In the same meta-analysis, constipation was one of many gut complaints reported across 8 placebo-controlled studies, with 32 events on creatine and 19 on placebo, and the difference was not significant. — women in 8 placebo-controlled creatine studies reporting gastrointestinal symptoms Evidence A source
  GI symptoms 32 in creatine groups vs 19 in placebo groups; no significant difference when stratified by dose; constipation not analyzed separately
• Observational data from 10,721 US adults in NHANES link higher creatine intake from food with 19 percent lower odds of chronic constipation. — US adults aged 20 and over, NHANES 2005-2010, 2-day dietary recall; constipation by Bristol stool type 1 or 2 (n = 10721) Evidence C source
  Chronic constipation adjusted OR 0.81 (95% CI 0.65 to 0.96) per unit of dietary creatine; chronic diarrhea risk about 4% higher per unit
• The same 2025 analysis concluded that cramping or pain can occur on creatine but is rare and no more common than on placebo. — participants of 685 creatine clinical trials (n = 26291) Evidence A source
  Incidence of GI issues and cramping/pain low and not different from placebo
• An ISSN expert review cites a survey of 219 athletes in which 90 used creatine and 27% reported cramping as a perceived negative effect. — survey of 219 athletes, 90 creatine users; NCAA baseball and football players using creatine (n = 219) Evidence E source
  38% of the 90 creatine users reported perceived negative effects; cramping 27%; self-report, no placebo group
• The only published report on creatine and kidney stones in a person describes one athlete with a past 11 mm stone who took creatine for two months and had no stone on ultrasound 14 months later. — healthy young athlete with a previous kidney stone treated by lithotripsy (n = 1) Evidence D source
  No stone recurrence on renal ultrasound 14 months after 2 months of creatine monohydrate
• The authors of the 2025 meta-analysis note that most creatine trials were short and that kidney safety data beyond one year remain sparse. — creatine supplementation trials reporting kidney outcomes (n = 21 studies) Evidence A source
  Long-term (over 1 year) kidney safety data sparse
• In 24-hour urine from 418 first-time kidney stone formers and 440 controls, stone formers had more creatine in their urine. — first-time symptomatic kidney stone formers and controls, prospective cohort; 24-hour urine NMR metabolomics (n = 858) Evidence C source
  Higher urine creatine in stone formers after adjustment for age and sex
• A meta-analysis of 10 RCTs that imaged muscle directly found creatine with training gave only a very small gain in muscle thickness, 0.04 to 0.06 in (0.10 to 0.16 cm). — healthy adults, at least 6 weeks of resistance training; MRI, CT or ultrasound measures of hypertrophy (n = 10 trials) Evidence A source
  Pooled standardized effect 0.11 (95% CrI -0.02 to 0.25); muscle thickness +0.04 to 0.06 in (0.10 to 0.16 cm) upper and lower body

The bottom line

Across 52 placebo-controlled trials in healthy athletes, creatine improved sprint performance (SMD -0.64, where lower is faster), jumping (SMD 0.33) and repeated-sprint ability (SMD -0.78), and the abstract gives no confidence intervals for any of them. Endurance is a different story. In 23 professional under-23 cyclists, 20 g a day for 6 days changed none of the measured outcomes. Over 8 trials, creatine taken for weeks did not shift the inflammation markers CRP (SMD -0.11, 95% CI -0.69 to 0.48) or IL-6. People who eat no meat start lower and their muscle stores respond clearly. In 15 young vegans and vegetarians taking 0.3 g per kg of body weight a day for 7 days, muscle creatine rose by 18.8 mmol/kg, yet repeated sprints did not improve. A review of 9 studies in vegetarians found supplements raised creatine in muscle, plasma and red blood cells, often above omnivore levels, with a moderate to high risk of bias and no effect on brain phosphocreatine. The brain claims are the weakest part. Five of six studies in 1542 adults aged 55 and over reported a link between creatine and memory or attention, but four of the six were cross-sectional and only one was rated good quality. A broader review, without pooled numbers, found creatine can raise brain creatine content, with somewhat equivocal results for thinking. The EU refused the claim that creatine improves attention and concentration, and also refused one wording about physical working capacity at the fatigue threshold, with no reason given in the register. Who should take care. Creatine nudges up serum creatinine, the usual blood test for kidney function, by a small and transient amount (MD 0.07, 95% CI 0.01 to 0.12) in a pooled analysis of 440 people, with no significant change in filtration rate. The units in that abstract are doubtful and not every pooled study was randomized, so anyone having kidney tests should tell the clinician they take it. Across 29 studies in 951 women, total adverse events did not differ from control (RR 1.24, 95% CI 0.51 to 2.98), and the authors note that adverse events were often poorly reported. A 2009 review of 10 trials found no evidence that creatine impairs heat loss or fluid balance in athletes exercising in the heat. We have no card on people who already have kidney disease, on pregnancy, children or drug interactions, so this page says nothing about those groups.

Sources

1. crtn-daily-r4-01 · cross-sectional
   Among 8,407 participants (57.8% female; mean age = 45.0 ± 21.5 years) reporting adherence to a single special diet, mean creatine intake was 0.82 ± 0.82 g/day, with 69.5% classified as having inadequate intake.
   Ann Nutr Metab, 2026 · checked 2026-10-03
2. crtn-daily-r4-07 · meta-analysis
   Lean mass (k = 5; n = 338) favored creatine: mean difference (MD) + 0.37 kg (95% CI + 0.05 to + 0.69; I² = 25%; τ² = 0.01; 95% PI -0.10 to + 0.84). Leg-press 1RM (k = 3; n = 111) improved with creatine: MD + 7.5 kg (95% CI + 2.2 to + 12.8; I² = 0%). Benefits were evident when creatine ≥ 5 g·day⁻¹ was combined with RT; trials using ≤ 3 g·day⁻¹ without RT showed no measurable effect.
   J Int Soc Sports Nutr, 2026 · checked 2026-10-03
3. crtn-daily-r4-02 · randomized controlled trial
   In the CM group, muscle creatine (Cr) and total muscle creatine (TCr) increased by 18.8 ± 13.1 mmol/kg (p < 0.05) and 30.8 ± 21.2 mmol/kg (p < 0.01), respectively.
   Physiol Rep, 2025 · checked 2026-10-03
4. crtn-daily-r4-03 · systematic review
   Creatine supplementation in vegetarians increased total creatine, creatine, and phosphocreatine concentrations in vastus lateralis and gastrocnemius muscle, plasma, and red blood cells, often to levels greater than omnivores.
   Int J Environ Res Public Health, 2020 · checked 2026-10-03
5. crtn-daily-r4-04 · meta-research
   Creatine monohydrate was the most commonly used formulation, reported in 275 (80.2%) trials; however, 53 (15.5%) reports did not specify the exact creatine form used. Bioavailability was mentioned in only 38 (11.1%) reports, most frequently in the discussion section.
   Nutrients, 2026 · checked 2026-10-03
6. crtn-daily-r4-05 · network meta-analysis
   Creatine supplementation demonstrated superior effects for muscle strength (SMD = 0.46, 95% CI: 0.29 to 0.63, SUCRA = 82.4%)
   Nutrients, 2026 · checked 2026-10-03
7. crtn-daily-r4-06 · network meta-analysis
   Cr supplementation significantly improved sprint performance (SMD = -0.64; p = 0.04), jump performance (SMD = 0.33; p = 0.002), RSA (SMD = -0.78; p = 0.01), and UME (SMD = 0.43; p = 0.01) versus placebo
   J Int Soc Sports Nutr, 2026 · checked 2026-10-03
8. crtn-daily-r4-09 · randomized controlled trial
   However, no significant group-by-time interaction effect was found for any of the study outcomes (all p > 0.05).
   J Int Soc Sports Nutr, 2024 · checked 2026-10-03
9. ev-crbf-01 · meta-analysis
   Creatine supplementation showed significant positive effects on memory (SMD = 0.31, 95% CI: 0.18-0.44, Hedges's g = 0.3003, 95% CI: 0.1778-0.4228)
   Front Nutr, 2024 · checked 2026-10-07
10. ev-crbf-04 · randomized controlled trial
    Creatine significantly reduced fatigue in terms of FAT by 8 ± 7% (Wilcoxon’s Z26 = − 2.84, p = 0.002) at 2 a.m. and 4 a.m. pooled.
    Scientific Reports, 2024 (Gordji-Nejad et al.) · checked 2026-10-07
11. ev-crbf-06 · randomized controlled trial
    It was concluded that, during sleep deprivation with moderate-intensity exercise, creatine supplementation only affects performance of complex central executive tasks.
    Physiol Behav, 2007 · checked 2026-10-07
12. ev-crbf-08 · randomized controlled trial
    CONCLUSION: Creatine supplementation improved physical (strength endurance) and prolonged cognitive (Stroop accuracy) performance, yet it did not combat MF-induced impairments in short sport-specific psychomotor or cognitive (Flanker) performance.
    Med Sci Sports Exerc, 2020 · checked 2026-10-07
13. ev-crmg-01 · meta-analysis
    Compared with resistance training alone (RT), resistance training plus creatine (RT + CR) produced significant increases in upper-body strength (g = 0.54, p < 0.001), lower-body strength (g = 0.55, p < 0.001), lean mass (g = 0.30, p < 0.001), and body mass (g = 0.12, p = 0.04), and a significant reduction in body-fat percentage (g = -0.14, p = 0.02).
    J Int Soc Sports Nutr, 2026 · checked 2026-10-06
14. ev-crmg-02 · meta-analysis
    Compared with resistance training (RT) alone, creatine supplementation increased LBM by 1.14 kg (95% CI 0.69 to 1.59), and reduced body fat percentage by -0.88% (95% CI -1.66 to -0.11) and body fat mass by -0.73 kg (95% CI -1.34 to -0.11).
    J Strength Cond Res, 2024 · checked 2026-10-06
15. ev-crmg-05 · meta-analysis
    In comparison with a placebo, creatine supplementation combined with resistance training significantly increased upper-body (WMD = 4.43 kg, p < 0.001) and lower-body strength (WMD = 11.35 kg, p < 0.001).
    Nutrients, 2024 · checked 2026-10-06
16. ev-crwl-01 · meta-analysis
    Adults (<50 years of age) who supplemented with creatine and performed resistance exercise experienced a very small, yet significant reduction in body fat percentage (-1.19%, p = 0.006); however, no difference was found in absolute fat mass (-0.18 kg, p = 0.76).
    Nutrients, 2023 · checked 2026-10-07
17. ev-crwl-02 · meta-analysis
    Compared with resistance training (RT) alone, creatine supplementation increased LBM by 1.14 kg (95% CI 0.69 to 1.59), and reduced body fat percentage by -0.88% (95% CI -1.66 to -0.11) and body fat mass by -0.73 kg (95% CI -1.34 to -0.11).
    J Strength Cond Res, 2024 · checked 2026-10-07
18. ev-crwl-03 · meta-analysis
    No significant difference emerged for fat mass (g = -0.10, p = 0.14).
    J Int Soc Sports Nutr, 2026 · checked 2026-10-07
19. ev-crwl-08 · controlled trial
    CrS and P1 demonstrated similar decreases in body weight and percent body fat.
    Med Sci Sports Exerc, 2001 · checked 2026-10-07
20. crtn-daily-r4-10 · meta-analysis
    Creatine supplementation is associated with a modest, transient increase in serum creatinine levels, likely due to metabolic turnover rather than renal impairment. No significant changes were observed in GFR, suggesting preserved kidney function.
    BMC Nephrol, 2025 · checked 2026-10-03
21. ev-crbf-10 · randomized controlled trial
    Creatine supplementation was well tolerated, with no reports of gastrointestinal distress or other adverse physical symptoms.
    Nutrients, 2026 · checked 2026-10-07
22. ev-crcon-01 · meta-analysis
    There were no significant differences in total adverse events, (risk ratio (RR) 1.24 (95% CI 0.51, 2.98)), gastrointestinal events, (RR 1.09 (95% CI 0.53, 2.24)), or weight gain, (mean difference (MD) 1.24 kg pre-intervention, (95% CI -0.34, 2.82)) to 1.37 kg post-intervention (95% CI -0.50, 3.23)), in CrM supplemented females, when stratified by dosing regimen and subject to meta-analysis.
    Nutrients, 2020 · checked 2026-10-07
23. ev-crcon-03 · RCT
    Moreover, diarrhoea was more frequent in the C10 group as compared with the placebo group (55.6% vs. 35.0%, p < 0.05).
    Res Sports Med, 2008 · checked 2026-10-07
24. ev-crcon-05 · RCT
    Four subjects reported mild gastrointestinal discomfort with CRE + CAF, with no side effects reported in other groups.
    J Strength Cond Res, 2016 · checked 2026-10-07
25. ev-crcon-06 · Cochrane review
    No trial reported any clinically relevant adverse event.
    Cochrane Database Syst Rev, 2013 · checked 2026-10-07
26. ev-crcr-01 · systematic review
    While more studies reported GI issues (PLA 28/652 or 4.3%, Cr 63/685 or 9.2%, p < 0.001) and muscle cramping/pain (PLA 6/652 or 0.9%, Cr 20/685 or 2.9%, p = 0.008) with creatine supplementation, there were no significant differences in these side effects when the number of participants experiencing GI issues (PLA 545/13,452 or 4.2%, Cr 708/12,839 or 5.51%, p = 0.820) or muscle cramping/pain (PLA 9/13,452 or 0.07%, Cr 67/12,839 or 0.52%, p = 0.085) is evaluated in all of these studies.
    J Int Soc Sports Nutr, 2025, Safety of creatine supplementation: analysis of the prevalence of reported side effects in clinical trials and adverse event reports · checked 2026-10-07
27. ev-crcr-03 · meta-analysis
    No evidence supports the concept that creatine supplementation either hinders the body's ability to dissipate heat or negatively affects the athlete's body fluid balance.
    J Athl Train, 2009 · checked 2026-10-07
28. ev-crcr-10 · meta-analysis
    The findings indicate that creatine supplementation does not induce renal damage in the studied amounts and durations.
    J Ren Nutr, 2019 · checked 2026-10-07
29. ev-crks-02 · meta-analysis
    A total of 5 studies evaluating GFR before and after intervention were included in the meta-analysis. ... The meta-analysis revealed a non-statistically significant differences in GFR following creatine supplementation compared to control.
    BMC Nephrol, 2025 · checked 2026-10-07
30. ev-crks-04 · meta-analysis
    The findings indicate that creatine supplementation does not induce renal damage in the studied amounts and durations.
    J Ren Nutr, 2019 · checked 2026-10-07
31. ev-crks-06 · RCT
    The decrease in cystatin C indicates that high-dose creatine supplementation over 3 months does not provoke any renal dysfunction in healthy males undergoing aerobic training.
    Eur J Appl Physiol, 2008 · checked 2026-10-07
32. ev-crks-08 · meta-analysis
    No evidence supports the concept that creatine supplementation either hinders the body's ability to dissipate heat or negatively affects the athlete's body fluid balance.
    J Athl Train, 2009 · checked 2026-10-07
33. ev-crmg-09 · meta-analysis
    Creatine supplementation is associated with a modest, transient increase in serum creatinine levels, likely due to metabolic turnover rather than renal impairment.
    BMC Nephrol, 2025 · checked 2026-10-06
34. ev-crmg-11 · randomized crossover trial
    However, levels of DHT increased by 56% after 7 days of creatine loading and remained 40% above baseline after 14 days maintenance (P < 0.001).
    Clin J Sport Med, 2009 · checked 2026-10-06
35. ev-crwl-04 · meta-analysis
    A pooled analysis of 61 trials revealed that Cr supplementation significantly increased FFM (weighted mean difference [WMD]: 1.39 kg; 95% confidence intereval (CI): 1.07,1.70; p < 0.001) and body mass (WMD: 0.89 kg; 95% CI: 0.76,1.01; p < 0.001) without significant effects on FM, BMI, and BFP.
    J Int Soc Sports Nutr, 2025 · checked 2026-10-07
36. ev-crwl-09 · RCT
    After the 7-day wash-in, the supplement group gained 0.51 ± 1.79 kg more lean body mass than the control group (p = 0.03).
    Nutrients, 2025 · checked 2026-10-07
37. ev-crwl-13 · meta-analysis
    Creatine supplementation was associated with a small but statistically significant increase in serum creatinine (MD: 0.07 µmol/L; 95% CI: 0.01 to 0.12; p = 0.03).
    BMC Nephrol, 2025 · checked 2026-10-07
38. crtn-daily-r4-08 · meta-analysis
    Chronic effects of creatine on CRP (SMD = -0.11; 95% CI: -0.69 to 0.48; p = 0.73; I² = 0%) and IL-6 (SMD = -0.06; 95% CI: -0.64 to 0.53; p = 0.84; I² = 0%) were also no significant.
    Front Immunol, 2026 · checked 2026-10-03
39. crtn-daily-r4-12 · meta-analysis
    No evidence supports the concept that creatine supplementation either hinders the body's ability to dissipate heat or negatively affects the athlete's body fluid balance.
    J Athl Train, 2009 · checked 2026-10-03
40. crtn-daily-r4-15 · EU claims register
    POL-HC-6994 Creatine Improves mental attentiveness Improved powers of concentration and ability to absorb information Assists in mental performance Non-authorised
    EU Register on nutrition and health claims, claim POL-HC-6994, snapshot 2026-09-21 · checked 2026-10-03
41. crtn-daily-r4-16 · EU claims register
    POL-HC-6993 Creatine Creatine can help enhance physical working capacity at fatigue threshold Non-authorised
    EU Register on nutrition and health claims, claim POL-HC-6993, snapshot 2026-09-21 · checked 2026-10-03
42. ev-crbf-13 · regulatory register entry
    POL-HC-6995 Creatine Improves mental attentiveness also in the elderly Non-authorised
    EU Register on nutrition and health claims, claim POL-HC-6995, snapshot 2026-09-21 · checked 2026-10-07
43. ev-crcon-09 · regulatory register
    POL-HC-6365 Creatine Creatine increases physical performance in successive bursts of short-term, high intensity exercise Authorised
    EU Register on nutrition and health claims, claim POL-HC-6365, snapshot 2026-09-21 · checked 2026-10-07
44. ev-crcr-11 · position statement
    Unsubstantiated anecdotal claims described in the popular media as well as rare case reports described in the literature without rigorous, systematic causality assessments have been refuted in numerous well-controlled clinical studies showing that creatine supplementation does not increase the incidence of musculoskeletal injuries [22, 111, 112, 241], dehydration [111, 112, 117, 122, 127–129, 242], muscle cramping [76, 106, 111, 112, 117], or gastrointestinal upset [22, 111, 112, 241].
    J Int Soc Sports Nutr, 2017, International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine · checked 2026-10-07
45. ev-crcr-14 · narrative review
    In summary, experimental and clinical research does not validate the notion that creatine supplementation causes dehydration and muscle cramping.
    J Int Soc Sports Nutr, 2021, Common questions and misconceptions about creatine supplementation: what does the scientific evidence really show? · checked 2026-10-07
46. ev-crcr-15 · narrative review
    Considering these new published findings, little evidence exists that creatine supplementation in the heat presents additional risk, and this should be taken into consideration as position statements and other related documents are published.
    Br J Sports Med, 2008, Putting to rest the myth of creatine supplementation leading to muscle cramps and dehydration · checked 2026-10-07
47. ev-crks-11 · narrative review
    Similar to the case report by Pritchard and Kalra [51], these additional case reports were confounded by medications, pre-existing kidney disease, concomitant supplement ingestion, inappropriate creatine dosages (e.g., 100 X recommended dose), and anabolic androgenic steroid use.
    Journal of the International Society of Sports Nutrition, 2021, Common questions and misconceptions about creatine supplementation: what does the scientific evidence really show? · checked 2026-10-07
48. ev-crks-12 · narrative review
    In summary, experimental and controlled research indicates that creatine supplementation, when ingested at recommended dosages, does not result in kidney damage and/or renal dysfunction in healthy individuals.
    Journal of the International Society of Sports Nutrition, 2021, Common questions and misconceptions about creatine supplementation: what does the scientific evidence really show? · checked 2026-10-07
49. ev-crmg-12 · position stand
    Nor has the literature provided any support that creatine promotes renal dysfunction [22, 51, 85, 114, 156, 172, 243–248] or has long-term detrimental effects [22, 23, 53, 155, 172].
    Journal of the International Society of Sports Nutrition, 2017, International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine · checked 2026-10-06
50. ev-crmg-13 · regulatory register entry
    POL-HC-8493 Creatine Daily creatine consumption can enhance the effect of resistance training on muscle strength in adults over the age of 55. -/- Authorised
    EU Register on nutrition and health claims, claim POL-HC-8493, snapshot 2026-09-21 · checked 2026-10-06
51. ev-crwl-10 · review
    The initial loading phase of creatine supplementation (i.e. 20 g/day for 5-7 days) typically results in a 1-3 kg increase in body mass, mostly attributable to net body water retention [75, 76].
    Journal of the International Society of Sports Nutrition, 2021, Common questions and misconceptions about creatine supplementation: what does the scientific evidence really show? · checked 2026-10-07
52. ev-crwl-11 · review
    In summary, creatine supplementation does not increase fat mass across a variety of populations.
    Journal of the International Society of Sports Nutrition, 2021, Common questions and misconceptions about creatine supplementation: what does the scientific evidence really show? · checked 2026-10-07
53. ev-crwl-12 · position stand
    The only consistently reported side effect from creatine supplementation that has been described in the literature has been weight gain [5, 22, 46, 78, 91, 92, 112].
    Journal of the International Society of Sports Nutrition, 2017, International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine · checked 2026-10-07
54. crtn-daily-r4-11 · meta-analysis
    There were no significant differences in total adverse events, (risk ratio (RR) 1.24 (95% CI 0.51, 2.98)), gastrointestinal events, (RR 1.09 (95% CI 0.53, 2.24)), or weight gain
    Nutrients, 2020 · checked 2026-10-03
55. ev-crbf-03 · meta-analysis
    Subgroup analyses revealed a significant improvement in memory in older adults (66-76 years) (SMD = 0.88; 95%CI, 0.22-1.55; I2 = 83%; P = 0.009) compared with their younger counterparts (11-31 years) (SMD = 0.03; 95%CI, -0.14 to 0.20; I2 = 0%; P = 0.72).
    Nutr Rev, 2023 · checked 2026-10-07
56. ev-crbf-05 · randomized controlled trial
    Although the effect is less pronounced than with a high dose of 0.35 g/kg, there is still an improvement of up to 12%.
    Nutrients, 2026 · checked 2026-10-07
57. ev-crbf-07 · randomized controlled trial
    These results suggest that six weeks of creatine supplementation (0.03/g/kg/day) does not improve cognitive processing in non-sleep deprived young adults.
    Physiol Behav, 2008 · checked 2026-10-07
58. ev-crbf-09 · randomized controlled trial
    Several long COVID symptoms (including body aches, breathing problems, difficulties concentrating, headache, and general malaise) were significantly reduced in creatine-glucose group at 8-wk follow-up (p≤0.05); the effect sizes for reducing body aches, difficulties concentrating, and headache were 1.33, 0.80, and 1.12, respectively, suggesting a large effect of creatine-glucose mixture for these outcomes.
    J Nutr Sci Vitaminol (Tokyo), 2024 · checked 2026-10-07
59. ev-crbf-11 · meta-analysis
    No statistically significant difference was reported in measures of renal or hepatic function.
    Nutrients, 2020 · checked 2026-10-07
60. ev-crcon-04 · RCT
    Main side effects were gastrointestinal complaints.
    Nutr Res, 2008 · checked 2026-10-07
61. ev-crcon-07 · meta-analysis
    Adverse events were mild and similar to placebo; renal indices were unchanged.
    J Int Soc Sports Nutr, 2026 · checked 2026-10-07
62. ev-crcr-04 · non-randomized controlled study
    The incidence of cramping or injury in Division IA football players was significantly lower or proportional for creatine users compared with nonusers.
    J Athl Train, 2003, Cramping and Injury Incidence in Collegiate Football Players Are Reduced by Creatine Supplementation · checked 2026-10-07
63. ev-crcr-05 · non-randomized controlled study
    Creatine supplementation does not appear to increase the incidence of injury or cramping in Division IA college football players.
    Mol Cell Biochem, 2003, Creatine supplementation during college football training does not increase the incidence of cramping or injury · checked 2026-10-07
64. ev-crcr-06 · RCT
    The frequency of symptomatic muscle cramps decreased by 60% in the creatine monohydrate treatment group (6.2+/-0.8 vs 2.6+/-1.8 times/4 weeks, P<0.05) during the treatment period.
    Nephrol Dial Transplant, 2002, Creatine monohydrate treatment alleviates muscle cramps associated with haemodialysis · checked 2026-10-07
65. ev-crcr-07 · systematic review
    The studies testing L-carnitine and creatine monohydrate were the only ones deemed to have a low risk of bias.
    Semin Dial, 2024 · checked 2026-10-07
66. ev-crcr-08 · Cochrane systematic review
    One trial reported a significant deterioration of activities of daily living (mean difference 0.54 on a 1 to 10 scale; 95% CI 0.14 to 0.93) and an increase in muscle pain during high-dose creatine treatment in McArdle disease.
    Cochrane Database Syst Rev, 2013 · checked 2026-10-07
67. ev-crcr-09 · meta-analysis
    There were no significant differences in total adverse events, (risk ratio (RR) 1.24 (95% CI 0.51, 2.98)), gastrointestinal events, (RR 1.09 (95% CI 0.53, 2.24)), or weight gain, (mean difference (MD) 1.24 kg pre-intervention, (95% CI -0.34, 2.82)) to 1.37 kg post-intervention (95% CI -0.50, 3.23)), in CrM supplemented females, when stratified by dosing regimen and subject to meta-analysis.
    Nutrients, 2020 · checked 2026-10-07
68. ev-crcr-12 · position statement
    While some have suggested that individuals with pre-existing renal disease consult with their physician prior to creatine supplementation in an abundance of caution, these studies and others have led researchers to conclude that there is no compelling evidence that creatine supplementation negatively affects renal function in healthy or clinical populations [5, 6, 22, 53, 259, 266, 267].
    J Int Soc Sports Nutr, 2017, International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine · checked 2026-10-07
69. ev-crks-05 · meta-analysis
    No statistically significant difference was reported in measures of renal or hepatic function.
    Nutrients, 2020 · checked 2026-10-07
70. ev-crks-07 · RCT
    Eight weeks of creatine supplementation is safe and does not compromise the renal function of patients with peripheral arterial disease.
    Ann Vasc Surg, 2020 · checked 2026-10-07
71. ev-crks-10 · case report
    This case underscores the potential risks of high-dose creatine use in adolescents and highlights the importance of kidney function monitoring in athletes using sports supplements.
    Pediatr Nephrol, 2025 · checked 2026-10-07
72. ev-crmg-03 · meta-analysis
    A pooled analysis of 61 trials revealed that Cr supplementation significantly increased FFM (weighted mean difference [WMD]: 1.39 kg; 95% confidence intereval (CI): 1.07,1.70; p < 0.001) and body mass (WMD: 0.89 kg; 95% CI: 0.76,1.01; p < 0.001) without significant effects on FM, BMI, and BFP.
    J Int Soc Sports Nutr, 2025 · checked 2026-10-06
73. ev-crmg-06 · meta-analysis
    Lean mass (k = 5; n = 338) favored creatine: mean difference (MD) + 0.37 kg (95% CI + 0.05 to + 0.69; I² = 25%; τ² = 0.01; 95% PI -0.10 to + 0.84).
    J Int Soc Sports Nutr, 2026 · checked 2026-10-06
74. ev-crmg-07 · meta-analysis
    Upper-body muscle strength (SMD: 0.25; 95% CI: 0.06-0.44; I2 = 0%; P = 0.01), handgrip strength (SMD 0.23; 95% CI: 0.01-0.45; I2 = 0%; P = 0.04), and lean tissue mass (MD 1.08 kg; 95% CI: 0.77-1.38; I2 = 26%; P < 0.01) improved with creatine supplementation.
    JPEN J Parenter Enteral Nutr, 2024 · checked 2026-10-06
75. ev-crmg-08 · RCT
    After 12 months of training, both groups experienced similar changes in bone mineral density and geometry, bone speed of sound, lean tissue and fat mass, muscle thickness, and muscle strength.
    Nutr Health, 2021 · checked 2026-10-06
76. ev-crmg-10 · meta-analysis
    There were no significant differences in total adverse events, (risk ratio (RR) 1.24 (95% CI 0.51, 2.98)), gastrointestinal events, (RR 1.09 (95% CI 0.53, 2.24)), or weight gain, (mean difference (MD) 1.24 kg pre-intervention, (95% CI -0.34, 2.82)) to 1.37 kg post-intervention (95% CI -0.50, 3.23)), in CrM supplemented females, when stratified by dosing regimen and subject to meta-analysis.
    Nutrients, 2020 · checked 2026-10-06
77. ev-crwl-05 · meta-analysis
    When pooling the data, body fat percentage (mean difference = −0.55% (95% CI = −1.08, −0.03); p = 0.04) decreased to a greater extent after creatine supplementation compared to placebo.
    Journal of Functional Morphology and Kinesiology, 2019, Changes in Fat Mass Following Creatine Supplementation and Resistance Training in Adults 50 Years of Age and Older: A Meta-Analysis · checked 2026-10-07
78. ev-crwl-06 · meta-analysis
    There was no statistically significant effect of creatine on LBM when combined with mixed exercise (MD, 0.74 kg; 95% CI, -3.89 to 5.36) or without exercise (MD, 0.03 kg; 95% CI, -0.65 to 0.70).
    Nutrition, 2022 · checked 2026-10-07
79. ev-crwl-07 · RCT
    Creatine supplementation during an exercise and weight-loss diet intervention increased lean tissue mass, promoted a greater reduction in body fat percentage, and improved muscular strength, endurance, and selected markers of cognitive function and memory.
    J Int Soc Sports Nutr, 2026 · checked 2026-10-07
80. crtn-daily-r4-13 · systematic review
    Five of the six (83.3%) studies reported a positive relationship between creatine and cognition in older adults, particularly in the domains of memory and attention. One study achieved a methodological quality rating of "good", two "fair", and three "poor".
    Nutr Rev, 2026 · checked 2026-10-03
81. crtn-daily-r4-14 · systematic review
    The review supported claims that creatine supplementation can increases brain creatine content but also demonstrated somewhat equivocal results for effects on cognition.
    Behav Brain Res, 2024 · checked 2026-10-03
82. ev-crbf-02 · meta-analysis
    However, no significant improvements were found on overall cognitive function or executive function.
    Front Nutr, 2024 · checked 2026-10-07
83. ev-crbf-12 · Cochrane review
    We found no randomised controlled trials for inclusion in this review.
    Cochrane Database Syst Rev, 2014 · checked 2026-10-07
84. ev-crcon-02 · meta-analysis
    Symptoms reported include nausea, vomiting, GIT discomfort, diarrhoea, constipation, irritable bowel, bloating, feeling of weight gain, dyspepsia, indigestion, decreased appetite.
    Nutrients, 2020 · checked 2026-10-07
85. ev-crcon-08 · cross-sectional study
    In Model 4, after adjusting for potential confounders such as sex, age, race/ethnicity, education, family income-to-poverty ratio, BMI, drinking status, smoking status, hypertension, diabetes, cardiovascular disease, and physical activity, the relationship between 2-day average dietary creatine intake and chronic constipation risk remained significantly negative (adjusted OR = 0.81, 95% CI: 0.65 ∼ 0.96, p = 0.015).
    Front Nutr, 2025, Association of dietary creatine intake from meat protein sources with different types of intestinal problems: insights from NHANES 2005-2010 · checked 2026-10-07
86. ev-crcr-02 · systematic review
    This means that while individuals taking creatine supplements may experience GI issues and muscle cramping/pain, the incidence is low and not different from those taking placebos.
    J Int Soc Sports Nutr, 2025, Safety of creatine supplementation: analysis of the prevalence of reported side effects in clinical trials and adverse event reports · checked 2026-10-07
87. ev-crcr-13 · narrative review
    For example, in a survey involving 219 athletes, 90 participants reported using creatine with 34 of them (38%) reporting perceived negative effects such as cramping (27%) [77].
    J Int Soc Sports Nutr, 2021, Common questions and misconceptions about creatine supplementation: what does the scientific evidence really show? · checked 2026-10-07
88. ev-crks-01 · case report
    Two months of creatine monohydrate supplementation in an athlete with a history of kidney stones could not be associated with kidney stone recurrence in the long run.
    Tunis Med, 2022 · checked 2026-10-07
89. ev-crks-03 · meta-analysis
    Most included studies were of short to moderate duration; long-term safety data beyond one year remain sparse.
    BMC Nephrol, 2025 · checked 2026-10-07
90. ev-crks-09 · case-control
    Among NMR urine metabolites, stone formers had lower hippuric acid, trigonelline, 2-furoylglycine, imidazole, and citrate and higher creatine and alanine.
    J Am Soc Nephrol, 2022 · checked 2026-10-07
91. ev-crmg-04 · meta-analysis
    Multivariate analyses found similar small benefits for the combination of creatine supplementation and RT on changes in the upper and lower body muscle thickness (0.10-0.16 cm).
    Nutrients, 2023 · checked 2026-10-06