Do nuts help with weight loss?

Barely. In the largest meta-analysis of nut trials, 105 comparisons in 9,655 adults, eating nuts changed body weight by +0.2 lb (95% CI -0.2 to 0.6; metric: 0.09 kg, -0.09 to 0.27) against control diets, on high-certainty evidence. That settles the old worry that nuts are too fattening to eat. Other pooled trials find a loss of 0.49 to 0.99 lb (0.22 to 0.45 kg) at most, and a network meta-analysis of 152 food trials put nuts at 0.82 lb (0.37 kg), against the 8.6 lb (3.9 kg) it treats as the smallest loss that matters clinically.

Myth. Nuts are high in fat and calories, so many people avoid them when they want to lose weight. The trials do not support that. Eating nuts did not change body weight, and in a network meta-analysis of 105 trials no nut type raised weight, BMI or body fat. The one exception was hazelnut diets, which raised waist size.

What the trials found

Nuts added to a diet

A meta-analysis of 55 trials in adults eating nuts daily for more than 3 weeks found no change in weight, BMI or waist size, whether people were told to swap nuts for other foods or not. In a 2-year trial of 356 healthy older adults with a mean age of 69, adding walnuts to their usual diet made no significant difference to weight (-0.88 lb / -0.4 kg with walnuts, -1.3 lb (-0.6 kg) without, p = 0.67) or to body fat. The nuts in that trial were added to habitual eating, with no advice to cut anything else.

The small losses

Across 37 trials, almonds lowered body weight by 0.99 lb (95% CI 0.11 to 1.9; metric: 0.45 kg, 0.05 to 0.85), waist by 0.26 in (0.66 cm) and fat mass by 1.5 lb (0.66 kg) against control diets, on moderate-certainty evidence for weight. The effect was larger at 50 g a day or more, over 12 weeks or more, and against controls with no nuts rather than other snacks. A 2018 meta-analysis of randomized feeding trials found nut-enriched diets lowered weight by 0.49 lb (95% CI 0.09 to 0.97; metric: 0.22 kg, 0.04 to 0.44). These numbers are real and they are small. The authors of the network meta-analysis call the nut result trivial, and they discourage testing single foods for weight loss at all.

Nuts on a calorie-reduced diet

A review of 7 trials that put people on an energy-restricted diet with or without nuts found that every diet produced significant weight loss. Adding nuts gave significantly greater loss in 4 of the 7. The review did not pool them, so there is no single number for the extra.

Why nuts do not add the weight their calories suggest

These findings are about mechanism, not weight. A systematic review of 21 studies found that the body gets fewer calories from almonds, cashews, hazelnuts, pistachios, walnuts and peanuts than the standard label factors predict. In the almond trials, hunger scores fell by 1.15 mm on a rating scale. Nuts did not measurably raise calorie burning at rest (+28.6 calories a day, 95% CI -10.7 to 67.8), so that is not the explanation.

What observational data show

Across 5 cohorts with 520,331 people, higher nut intake went with a 7 percent lower risk of becoming overweight or obese (RR 0.93, 95% CI 0.88 to 0.98), with large differences between studies. In 3 US cohorts of 144,885 adults, each extra half serving of nuts a day tracked with 0.42 lb (0.19 kg) less weight gain over 4 years (95% CI -0.21 to -0.17). People who eat more nuts may live differently in other ways, and diet and weight were self-reported, so these figures cannot show that nuts caused the difference.

Who should be careful

Not for everyone. Nuts can cause severe, sometimes fatal allergic reactions. In European studies, 1.5 percent of people report a peanut allergy at some point in life (95% CI 1.0 to 2.1) and 0.9 percent a tree nut allergy (0.6 to 1.2). These are self-reported figures from studies mostly at moderate risk of bias. If you have either allergy, this page does not apply to you.

Portions matter more than the nut. Across 31 trials, eating nuts raised daily energy intake by 76.3 calories (95% CI 22.7 to 130), measured from 3-day food records. The trials still did not see weight rise, but if you eat nuts by the handful on top of everything else, the calories are not free.

What expert bodies say

The European Union refused to authorize the health claim that eating 1.1 oz (30 g) of nuts a day as part of an energy-restricted diet helps maintain a healthy weight. A refusal means the evidence did not meet EFSA's bar when it was assessed, and it is not proof that nuts have no effect. We found no US claim about nuts and weight.

How we searched

What would change this answer

• Long trials in which nuts replace snacks within a calorie-reduced diet, large enough to measure weight loss. The 7 trials that tried this disagreed, and we found none running now.
• A check of industry funding across the trials, which could shift how much weight the small losses deserve.
• Trials that compare nut types directly. Most comparisons between nuts today are indirect.

What nuts contain, per handful and per 3.5 oz (100 g), is on the nuts page.

Sources

1. ev-nutw-01 · Meta-analysis or systematic review · systematic review and meta-analysis of randomized controlled trials · n = 9655
   There was no effect of nuts compared with control on the primary outcome body weight (105 trial comparisons involving 9655 participants, MD 0.09 kg, [95% CI −0.09 to 0.27 kg], P = 0.340; substantial heterogeneity, I 2 = 63.2%, P‐heterogeneity < 0.01).
   
   Who: adults in randomized controlled trials of tree nuts and peanuts vs control diets
   Effect: body weight MD 0.2 lb (95% CI -0.2 to 0.6; metric: 0.09 kg, -0.09 to 0.27), 105 comparisons, I2 63.2%
   Certainty: GRADE high for body weight and BMI. Shows nuts do not add weight, not that they remove it.
   Obesity Reviews, 2021, 22(11):e13330 (Nishi et al.) · checked 2026-10-07 · we read the fulltext
2. ev-nutw-02 · Observational data · meta-analysis of prospective cohort studies · n = 520331
   Higher nut intake was associated with a decrease in the primary outcome of overweight/obesity incidence (RR 0.93 [95% CI 0.88 to 0.98], P < 0.01; substantial heterogeneity, I 2 = 90.0%, P‐heterogeneity < 0.01).
   
   Who: participants of five prospective cohort studies
   Effect: overweight/obesity incidence RR 0.93 (95% CI 0.88 to 0.98), I2 90%
   Certainty: GRADE moderate for incidence outcomes; association, residual confounding by healthier lifestyle possible.
   Obesity Reviews, 2021, 22(11):e13330 (Nishi et al.) · checked 2026-10-07 · we read the fulltext
3. ev-nutw-03 · Meta-analysis or systematic review · systematic review and meta-analysis of randomized trials · n = 55 studies
   Nut-enriched diet interventions did not result in changes in BW, BMI, or WC in studies either with or without substitution instructions.
   
   Who: adults (18 y or older) eating nuts daily for more than 3 weeks in clinical trials
   Effect: body weight SMD 0.01 (95% CI -0.07 to 0.08) without substitution instructions; -0.01 (-0.11 to 0.09) with
   Certainty: Fixed-effect model.
   Adv Nutr, 2021 · checked 2026-10-07 · we read the abstract
4. ev-nutw-04 · Meta-analysis or systematic review · systematic review and Bayesian network meta-analysis of RCTs · n = 9669
   Increased consumption of fish (MD - 0.85 kg, 95% CrI - 1.66, - 0.02; GRADE = low), whole grains (MD - 0.44 kg, 95% CrI - 0.88, 0.0; GRADE = very low), and nuts (MD - 0.37 kg, 95% CI - 0.72, - 0.01; GRADE = low) demonstrated trivial weight loss, well below minimal clinically important threshold (3.9 kg), when compared with the control group.
   
   Who: adults in randomized trials of single foods or food groups for weight loss
   Effect: nuts MD -0.82 lb (95% CI -1.6 to -0.02; metric: -0.37 kg, -0.72 to -0.01) vs control; GRADE low; below the 8.6 lb (3.9 kg) clinical threshold
   Certainty: Low certainty; authors discourage single-food weight-loss trials.
   Eur J Nutr, 2023 · checked 2026-10-07 · we read the abstract
5. ev-nutw-05 · Meta-analysis or systematic review · systematic review and dose-response meta-analysis of RCTs · n = 37 RCTs
   Pooled effect sizes indicated a significant reducing effect of almond consumption on body weight (WMD: -0.45 kg, 95% CI: -0.85, -0.05, p = 0.026), WC (WMD: -0.66 cm, 95% CI: -1.27, -0.04, p = 0.037), FM (WMD: -0.66 kg, 95% CI: -1.16, -0.17, p = 0.009), and hunger score (WMD: -1.15 mm, 95% CI: -1.98, -0.32, p = 0.006) compared with the control group.
   
   Who: adults in randomized controlled trials of almond supplementation
   Effect: body weight WMD -0.99 lb (95% CI -1.9 to -0.11; metric: -0.45 kg, -0.85 to -0.05); waist -0.26 in (-0.5 to -0.02; metric: -0.66 cm, -1.27 to -0.04); fat mass -1.5 lb (-2.6 to -0.37; metric: -0.66 kg, -1.16 to -0.17); hunger -1.15 mm
   Certainty: GRADE moderate for weight; larger effect with 50 g/day or more, 12 weeks or more, and nut-free controls (not snack controls).
   Obes Rev, 2024 · checked 2026-10-07 · we read the abstract
6. ev-nutw-06 · Meta-analysis or systematic review · systematic review and network meta-analysis of RCTs · n = 6768
   In the comparisons of nut consumption versus a control diet, there was no significant increase observed in any of the adiposity-related measures examined except for hazelnut-enriched diets, which raised WC.
   
   Who: adults in randomized controlled trials of tree nuts and peanuts
   Effect: no significant increase in BW, BMI, WC or BF% vs control; hazelnut raised WC
   Certainty: Indirect comparisons between nut types; effects small.
   Nutrients, 2021 · checked 2026-10-07 · we read the abstract
7. ev-nutw-07 · Meta-analysis or systematic review · meta-analysis of randomized feeding trials (trial arm of a combined cohort and trial meta-analysis) · n = —
   Compared with control diet, a nut-enriched diet was associated with a significant decrease in body weight (WMD: − 0.22 Kg, 95% CI: -0.44 to − 0.04; Fig. 3), BMI (WMD: -0.16 Kg/m2, 95% CI: -0.31 to − 0.01; Fig. 4), and waist circumference (WMD: − 0.51 cm, 95% CI: -0.95 to − 0.07; Fig. 4).
   
   Who: adults in randomized feeding trials with nuts
   Effect: body weight WMD -0.49 lb (95% CI -0.97 to -0.09; metric: -0.22 kg, -0.44 to -0.04); BMI -0.16 kg/m2; waist -0.2 in (-0.51 cm)
   Certainty: Substantial heterogeneity; effect clinically trivial.
   Nutrition & Metabolism, 2018, 15:46 (Li et al.) · checked 2026-10-07 · we read the fulltext
8. ev-nutw-08 · Meta-analysis or systematic review · systematic review and meta-analysis of randomized clinical trials · n = 31 trials
   Nut consumption was associated with increased energy intake (mean difference (MD) (nuts - control) = 76.3 kcal; 95% CI: 22.7, 130 kcal; P = 0.005).
   
   Who: adults in randomized clinical trials of nut consumption
   Effect: energy intake MD +76.3 calories (95% CI 22.7 to 130)
   Certainty: Energy intake from 3-day food records; the caution is about portion size.
   Crit Rev Food Sci Nutr, 2020 · checked 2026-10-07 · we read the abstract
9. ev-nutw-09 · Randomized controlled trial(s) · 2-year randomized parallel trial, walnuts about 15% of energy added to habitual diet · n = 356
   However, no significant differences were observed between the control and walnut groups regarding body weight (-0.6 kg and -0.4 kg, respectively, p = 0.67) or body fat (+0.9% and +1.3%, respectively, p = 0.53).
   
   Who: healthy elders, mean age 69, 67% women, Loma Linda cohort of the Walnuts and Healthy Aging study
   Effect: weight change -0.88 lb (-0.4 kg) walnut vs -1.3 lb (-0.6 kg) control (p = 0.67); body fat +1.3% vs +0.9% (p = 0.53)
   Certainty: Free-living, nuts added to habitual diet; one center of a two-center trial.
   Nutrients, 2018 · checked 2026-10-07 · we read the abstract
10. ev-nutw-10 · Meta-analysis or systematic review · scoping review of randomized controlled trials, no meta-analysis · n = 7 studies
    While all studies reported that energy restriction resulted in significant weight loss, the addition of nuts to ER diets demonstrated significantly greater weight loss in only approximately half of the included studies (4/7 studies).
    
    Who: adults in randomized controlled trials of energy-restricted diets with or without nuts
    Effect: greater weight loss with nuts in 4 of 7 trials; all energy-restricted diets produced significant loss
    Certainty: No pooled estimate; inconsistent trials.
    Nutr Res Rev, 2025 · checked 2026-10-07 · we read the abstract
11. ev-nutw-11 · Observational data · three prospective cohort studies, changes in intake vs 4-year weight change · n = 144885
    Increasing total consumption of nuts per 0.5 servings/day was associated with 0.19 kg less weight gain over 4 years (95% CI −0.21 to −0.17).
    
    Who: US men and women in the Health Professionals Follow-up Study, Nurses' Health Study and Nurses' Health Study II
    Effect: -0.19 kg (95% CI -0.21 to -0.17) per 4 years per 0.5 servings/day of total nuts
    Certainty: Self-reported diet and weight; adjusted for lifestyle changes, residual confounding possible.
    BMJ Nutrition, Prevention & Health, 2019, 2(2):90-99 (Liu et al.) · checked 2026-10-07 · we read the fulltext
12. ev-nutw-12 · Observational data · systematic review and dose-response meta-analysis of prospective studies · n = —
    In the dose-response meta-analysis, inverse associations were found for whole-grain (RRoverweight/obesity: 0.93; 95% CI: 0.89, 0.96), fruit (RRoverweight/obesity: 0.93; 95% CI: 0.86, 1.00; RRweight gain: 0.91; 95% CI: 0.86, 0.97), nut (RRabdominal obesity: 0.42; 95% CI: 0.31, 0.57), legume (RRoverweight/obesity: 0.88; 95% CI: 0.84, 0.93), and fish (RRabdominal obesity: 0.83; 95% CI: 0.71, 0.97) consumption and positive associations were found for refined grains (RRoverweight/obesity: 1.05; 95% CI: 1.00, 1.10), red meat (RRabdominal obesity: 1.10; 95% CI: 1.04, 1.16; RRweight gain: 1.14; 95% CI: 1.03, 1.26), and SSBs (RRoverweight/obesity: 1.05; 95% CI: 1.00, 1.11; RRabdominal obesity: 1.12; 95% CI: 1.04, 1.20).
    
    Who: adults in prospective observational studies
    Effect: abdominal obesity RR 0.42 (95% CI 0.31 to 0.57), dose-response; NutriGrade very low to low
    Certainty: Very low to low quality evidence per NutriGrade.
    Adv Nutr, 2019 · checked 2026-10-07 · we read the abstract
13. ev-nutw-13 · Observational data · systematic review with narrative synthesis of human and in vitro studies · n = 21 studies
    The ME of nuts was consistently lower than that predicted by Atwater factors for investigated nut types (almonds, cashews, hazelnuts, pistachios, walnuts, and peanuts).
    
    Who: human balance studies and in vitro digestion models of tree nuts and peanuts
    Effect: metabolizable energy consistently below Atwater predictions for almonds, cashews, hazelnuts, pistachios, walnuts and peanuts
    Certainty: Mixed human and lab studies; carbohydrate and protein digestibility not considered.
    Adv Nutr, 2023 · checked 2026-10-07 · we read the abstract
14. ev-nutw-14 · Observational data · systematic review and meta-analysis of acute feeding and energy expenditure studies · n = 1121
    The meta-analyses identified a nonsignificant increase in REE associated with nut consumption (weighted mean difference: 28.6 kcal/d; 95% CI: -10.7, 67.8 kcal/d).
    
    Who: adults in acute energy intake studies and energy expenditure studies
    Effect: resting energy expenditure WMD +28.6 calories/d (95% CI -10.7 to 67.8), not significant
    Certainty: Acute studies of 24 h or less, mixed designs; mechanism only.
    Adv Nutr, 2023 · checked 2026-10-07 · we read the abstract
15. ev-nutw-15 · Observational data · systematic review and meta-analysis of prevalence studies · n = 93 studies
    The overall pooled estimates for all age groups of self-reported lifetime prevalence were as follows: cow's milk (5.7%, 95% confidence interval 4.4-6.9), egg (2.4%, 1.8-3.0), wheat (1.6%, 0.9-2.3), soy (0.5%, 0.3-0.7), peanut (1.5%, 1.0-2.1), tree nuts (0.9%, 0.6-1.2), fish (1.4%, 0.8-2.0) and shellfish (0.4%, 0.3-0.6).
    
    Who: all age groups in European prevalence studies
    Effect: self-reported lifetime prevalence peanut 1.5% (1.0-2.1), tree nuts 0.9% (0.6-1.2)
    Certainty: Most studies at moderate risk of bias; nuts can cause severe, sometimes fatal reactions.
    Allergy, 2023 · checked 2026-10-07 · we read the abstract
16. ev-nutw-16 · Position of an expert body · EU health claim register entry · n = —
    POL-HC-7667 Nuts - peanuts and tree nuts (almonds, hazelnuts, pecans, pistachios and walnuts), excluding brazil, macadamia and cashew nuts Eating 30g of nuts per day as part of an energy restricted diet helps maintain a healthy weigh Non-authorised
    
    Who: EU food labeling
    Effect: claim POL-HC-7667 non-authorized
    Certainty: Non-authorized means evidence did not meet EFSA's bar at assessment, not proof of no effect.
    EU Register on nutrition and health claims (European Commission) · checked 2026-10-07 · we read the dataset