Do chia seeds lower blood pressure?

Probably a little. A 2025 meta-analysis of 8 randomized trials found systolic pressure 7.19 mmHg lower and diastolic 6.04 mmHg lower with chia than without it, and the authors themselves flag how limited those 8 small trials are. Four more meta-analyses point the same way, with drops between about 3 and 8 mmHg. The single trials described below gave adults 0.88 to 1.4 oz (25 to 40 g) of chia a day for 8 to 12 weeks. The first of these reviews, in 2018, rated the quality of all its evidence low or very low.

Unsettled. The direction is consistent and the size is not. Every review pools much the same handful of small trials, several findings appear only at the higher doses, and one review saw the systolic drop only in people who started below 140 mmHg. Nobody has run a large trial in people with high blood pressure, and no trial has looked at strokes or heart attacks.

What the trials found

The meta-analyses

The 2025 GRADE-assessed review pooled 8 randomized trials and found systolic pressure 7.19 mmHg lower, with a confidence interval from 3.73 to 10.63, and diastolic 6.04 mmHg lower. In its subgroup analysis the systolic effect was significant only in participants whose starting systolic pressure was under 140 mmHg, and it did not depend on the dose given. A second 2025 review, of 8 trials in 372 adults, found diastolic 7.49 mmHg lower and systolic 5.61 mmHg lower. Its trial set overlaps with the first.

A 2024 dose-response analysis of 10 publications found systolic pressure 7.87 mmHg lower and diastolic 6.33 mmHg lower, with about 2.20 mmHg less systolic for each extra 10 g of chia a day. Its authors rated the included studies mostly low quality, and the systolic result varied a lot between trials. Their conclusion was cautious: chia might have a beneficial effect on lowering blood pressure.

Two reviews found smaller numbers. In overweight and obese adults, systolic pressure was 3.27 mmHg lower across 7 trials, and the diastolic drop of 2.69 mmHg did not reach significance. A 2024 meta-regression of 14 trials in 835 people found 2.78 mmHg less systolic, seen only at the higher doses. The first chia meta-analysis, in 2018, found diastolic pressure 7.14 mmHg lower in its higher-dose subgroup and no difference in its main pooled analyses. An umbrella review of 8 of these meta-analyses, covering about 2500 people, found a moderate standardized drop in diastolic pressure and a very small one in systolic.

Single trials

The individual trials split. In a 12-week crossover trial of 20 people with well-controlled type 2 diabetes, about 37 g a day of one chia brand lowered systolic pressure by 6.3 mmHg against wheat bran. In 42 adults with type 2 diabetes, 40 g a day for 12 weeks lowered systolic pressure compared with no supplement, and the abstract does not give the size in mmHg. In people with high triglycerides on a low-calorie diet, adding 30 g a day for 8 weeks lowered diastolic pressure by 8.4 mmHg from baseline, more than the diet alone or the diet with fish oil.

The one double-blind trial with a placebo seed found nothing. In 62 overweight postmenopausal women with normal blood pressure, 25 g a day of whole or milled chia for 10 weeks did not change blood pressure against poppy seed.

In people with high blood pressure

Only one small trial recruited people with hypertension. Over 12 weeks, 35 g a day of chia flour lowered mean clinic blood pressure, a single average across the heartbeat rather than the systolic reading, from 111.3 to 100.1 mmHg in 10 people who were taking blood pressure drugs. In the 9 people taking no drugs, mean pressure did not fall, but systolic pressure went from 146.8 to 137.3 mmHg. The 7 people on drugs and placebo showed no change. These are changes within each group, in 26 people altogether.

Who should be careful

Not for everyone. Chia allergy exists. The EU food safety agency notes allergic reactions to chia, including one case of anaphylaxis, and cross-reactivity in people allergic to peanut or sesame. Nobody knows how common it is. If you are allergic to peanut or sesame, that cross-reactivity is the reason to be wary of chia.

If you take blood pressure medicine, the small hypertension trial above found chia lowered mean pressure on top of the drugs, from 111.3 to 100.1 mmHg in 10 people. That is a reason to tell whoever manages your treatment before you start eating chia daily, so that readings can be checked.

Very large amounts carry a separate risk. One woman with controlled hypertension, eating six tablespoons of chia and five handfuls of almonds a day to manage bowel symptoms, developed oxalate kidney damage, and improved on a low-oxalate diet. That is a single case report, the almonds contributed, and the amount was far above the usual one to two tablespoons.

We found no evidence on chia and blood pressure in pregnancy or in children.

For ordinary amounts the trials show no signal of harm. Reviewing human studies that used up to 50 g a day for up to six months, EFSA found no chia-related adverse events, though those trials were not designed to look for harm.

What expert bodies say

We found no position on chia for blood pressure from the American Heart Association, the US Office of Dietary Supplements, EFSA, the WHO or NICE, and the EU health claims register has no entry for chia. The only official document is EFSA's 2019 safety opinion on chia as a novel food, which covers allergy and the absence of adverse events up to 50 g a day, and does not address blood pressure.

How we searched

What would change this answer

• A properly sized randomized trial in adults with high blood pressure. Today that group rests on one trial of 26 people, and one review saw the systolic effect only in people below 140 mmHg.
• A trial long enough to measure strokes or heart attacks. Every chia trial so far uses blood pressure as a stand-in, and the single trials described here ran 8 to 12 weeks.
• A clear dose answer. One review found the effect grew by about 2.20 mmHg systolic per extra 10 g a day, another found no dose dependence, and two saw an effect only at the higher doses.
• We found no chia blood pressure trial under way in the local ClinicalTrials.gov layer, so we know of no result due that would change this answer.

For what else chia does and how much a serving holds, see the chia seeds page.

Sources

1. ev-chbp-01 · Meta-analysis or systematic review · GRADE-assessed systematic review and dose-response meta-analysis of randomized controlled trials · n = 8 trials
   The findings revealed a significant reduction in SBP (WMD: -7.19 mmHg; 95% CI, -10.63 to -3.73; P < .001) and DBP (WMD: -6.04 mmHg, 95% CI, -9.58 to -2.49; P = .001).
   
   Who: adults in randomized controlled trials of chia seed consumption, searched to August 2023
   Effect: SBP WMD -7.19 mmHg (95% CI -10.63 to -3.73); DBP WMD -6.04 mmHg (95% CI -9.58 to -2.49)
   Certainty: Only 8 small trials; authors flag the limited data. GRADE ratings per outcome not in the abstract; full text paywalled (no PMC).
   Nutrition Reviews, 2025, The Effect of Chia Seed on Blood Pressure, Body Composition, and Glycemic Control: A GRADE-Assessed Systematic Review and Dose-Response Meta-Analysis of Randomized Controlled Trials · checked 2026-10-07 · we read the abstract
2. ev-chbp-02 · Meta-analysis or systematic review · systematic review and meta-analysis of randomized controlled trials, subgroup analysis · n = 8 trials
   Subgroup analysis indicated that the effect of chia seed on SBP was significant in participants with a baseline SBP of less than 140 mmHg, but the effect was not dependent on the administered dose.
   
   Who: subgroups of adults in 8 randomized trials of chia seed, by baseline systolic pressure and dose
   Effect: SBP effect significant when baseline SBP < 140 mmHg; no dose dependence
   Certainty: Subgroups of an 8-trial pool; few trials in people with established hypertension.
   Nutrition Reviews, 2025, The Effect of Chia Seed on Blood Pressure, Body Composition, and Glycemic Control: A GRADE-Assessed Systematic Review and Dose-Response Meta-Analysis of Randomized Controlled Trials · checked 2026-10-07 · we read the abstract
3. ev-chbp-03 · Meta-analysis or systematic review · systematic review and meta-analysis of randomized controlled trials · n = 372
   The results showed that chia consumption significantly reduced DBP (WMD: -7.49 mmHg; 95% CI: -9.64, -5.34; P < 0.001) and SBP (WMD: -5.61 mmHg; 95% CI: -8.77, -2.44; P = 0.001).
   
   Who: adults in randomized controlled trials of chia seed supplementation, searched to October 2024
   Effect: DBP WMD -7.49 mmHg (95% CI -9.64 to -5.34); SBP WMD -5.61 mmHg (95% CI -8.77 to -2.44)
   Certainty: Small total sample; overlapping trial set with the other chia meta-analyses; risk-of-bias grading not in the abstract.
   Clinical Therapeutics, 2025, The Effects of Chia Seed (Salvia hispanica L.) Consumption on Blood Pressure and Body Composition in Adults: A Systematic Review and Meta-analysis of Randomized Controlled Trials · checked 2026-10-07 · we read the abstract
4. ev-chbp-04 · Meta-analysis or systematic review · systematic review and dose-response meta-analysis of randomized controlled trials · n = 10 publications
   Chia consumption might have a beneficial effect on lowering blood pressure.
   
   Who: adults in randomized controlled trials of chia, searched to June 2023
   Effect: SBP MD -7.87 mmHg (95% CI -12.92 to -2.82, I2 71.3%); DBP MD -6.33 mmHg (95% CI -7.33 to -5.34, I2 0%); per 10 g/day SBP MD -2.20 mmHg (95% CI -3.75 to -0.66)
   Certainty: Authors rate included studies mostly low quality; high heterogeneity for SBP; HDL-C also fell.
   Complementary Therapies in Medicine, 2024, Effects of chia (Salvia hispanica. L) on anthropometric measures and other cardiometabolic risk factors: A systematic review and dose-response meta-analysis · checked 2026-10-07 · we read the abstract
5. ev-chbp-05 · Meta-analysis or systematic review · systematic review and meta-analysis of 10 randomized controlled trials · n = 7 trials for SBP, 5 for DBP
   The intervention group experienced a significant (MD: − 3.27 mmHg, 95% CI [− 6.28, − 0.27], I2 = 0.0%, p-value = 0.03) reduction of − 3.27 mmHg in systolic BP compared to the control group (Fig. 4A).
   
   Who: overweight and obese participants in randomized controlled trials of chia seed supplementation
   Effect: SBP MD -3.27 mmHg (95% CI -6.28 to -0.27, I2 0%); DBP MD -2.69 mmHg (95% CI -5.76 to 0.38, p = 0.09)
   Certainty: 424 participants in the whole review; small trials. Results section read in PMC full text.
   Nutrition & Metabolism, 2024, Effects of chia seed (Salvia hispanica L.) supplementation on cardiometabolic health in overweight subjects: a systematic review and meta-analysis of RCTs · checked 2026-10-07 · we read the fulltext
6. ev-chbp-06 · Meta-analysis or systematic review · systematic review and meta-regression of randomized controlled trials · n = 835
   Moreover, although the decrease in systolic blood pressure (-2.78 mmHg) compared to the control group was statistically significant, it was only observed with the higher dosage.
   
   Who: participants in clinical trials of chia seed supplementation, searched to April 2024
   Effect: SBP -2.78 mmHg vs control, significant only in the higher-dose group
   Certainty: Confidence interval and dose cut-off not in the abstract; full text paywalled.
   Prostaglandins & Other Lipid Mediators, 2024, The impact of chia seeds on diabetes, blood pressure, lipid profile, and obesity indicators: Systematic review and meta-regression analysis of 14 randomized controlled trials · checked 2026-10-07 · we read the abstract
7. ev-chbp-07 · Meta-analysis or systematic review · systematic review and meta-analysis of randomized controlled trials · n = 12 trials
   The quality of all evidence assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach was low or very low.
   
   Who: healthy people, athletes, people with diabetes or metabolic syndrome in 12 randomized trials
   Effect: DBP MD -7.14 mmHg (95% CI -11.08 to -3.19) in the higher-dose subgroup; no difference in pooled main analyses; GRADE low or very low
   Certainty: Subgroup finding only; all outcomes surrogate markers.
   Nutr Rev, 2018 · checked 2026-10-07 · we read the abstract
8. ev-chbp-08 · Meta-analysis or systematic review · umbrella review of systematic reviews and meta-analyses of randomized controlled trials · n = about 2500
   Chia supplementation resulted in significant reductions in diastolic blood pressure (g = -0.550; 95% CI: -0.718 to -0.382), systolic blood pressure (g = -0.119; 95% CI: -0.228 to -0.010), total cholesterol (g = -0.300), LDL-C (g = -0.300), triglycerides (g = -0.200), waist circumference (g = -0.289), and C-reactive protein (g = -0.165).
   
   Who: participants in randomized controlled trials pooled by eight meta-analyses of chia supplementation
   Effect: DBP Hedges g -0.550 (95% CI -0.718 to -0.382); SBP g -0.119 (95% CI -0.228 to -0.010); GRADE moderate to low for most outcomes
   Certainty: Standardized effects only, no mmHg; overlapping trials across the pooled meta-analyses.
   Plant Foods Hum Nutr, 2025 · checked 2026-10-07 · we read the abstract
9. ev-chbp-09 · Randomized controlled trial(s) · randomized single-blind crossover controlled trial · n = 20
   Compared with the control treatment, Salba reduced systolic blood pressure (SBP) by 6.3 +/- 4 mmHg (P < 0.001), high-sensitivity C-reactive protein (hs-CRP) (mg/l) by 40 +/- 1.6% (P = 0.04), and vonWillebrand factor (vWF) by 21 +/- 0.3% (P = 0.03), with significant decreases in A1C and fibrinogen in relation to the Salba baseline but not with the control treatment.
   
   Who: 20 adults with well-controlled type 2 diabetes on usual therapy, aged 64 +/- 8, 37 +/- 4 g/day Salba chia or wheat bran
   Effect: SBP -6.3 +/- 4 mmHg vs control (P < 0.001)
   Certainty: Very small; single-blind; one research group (Salba brand).
   Diabetes Care, 2007 · checked 2026-10-07 · we read the abstract
10. ev-chbp-10 · Randomized controlled trial(s) · randomized placebo-controlled trial · n = 26
    While the PLA-MD group showed no changes in BP, there was a reduction in the mean clinical blood pressure (MBP) in the CHIA (111.5 ± 1.9 to 102.7 ± 1.5 mmHg, p < 0.001) and CHIA-MD (111.3 ± 2.2 to 100.1 ± 1.8 mmHg, p < 0.001) groups.
    
    Who: hypertensive adults, drug-treated (n = 10) or untreated (n = 9) on chia flour 35 g/day, or drug-treated on placebo (n = 7), 12 weeks
    Effect: mean clinic BP in drug-treated chia group 111.3 to 100.1 mmHg (p < 0.001); untreated chia group SBP 146.8 to 137.3 mmHg (p < 0.05); no change on placebo
    Certainty: Very small groups; within-group changes reported. Lowering on top of drugs means people on antihypertensives may see an added effect.
    Plant Foods Hum Nutr, 2014 · checked 2026-10-07 · we read the abstract
11. ev-chbp-11 · Randomized controlled trial(s) · randomized controlled trial, open control · n = 42
    RESULTS: Adjusted for gender and baseline values, the chia seed group had systolic BP (SBP) significantly reduced compared to control [t (1) = 2.867, p = 0.007, η 2 p = 0.174].
    
    Who: adults with type 2 diabetes keeping usual diet, activity and medication, 40 g/day chia or no supplement for 12 weeks
    Effect: SBP reduced vs control (adjusted, p = 0.007, partial eta squared 0.174); mmHg not in the abstract; no change in other outcomes
    Certainty: No placebo; effect size in mmHg not in the abstract.
    Nutr Health, 2021 · checked 2026-10-07 · we read the abstract
12. ev-chbp-12 · Randomized controlled trial(s) · randomized double-blind placebo-controlled trial · n = 62
    Pre-to-post measures of body composition, inflammation, blood pressure, augmentation index, and lipoproteins did not differ between chia seed (whole or milled) and placebo groups (all interaction effects, p>0.05).
    
    Who: overweight nondiseased postmenopausal women aged 49 to 75, 25 g/day chia (whole or milled) or poppy seed placebo, 10 weeks
    Effect: no difference vs placebo in blood pressure or augmentation index (all interaction p > 0.05)
    Certainty: Normotensive women; analysis on 56 completers.
    J Altern Complement Med, 2012 · checked 2026-10-07 · we read the abstract
13. ev-chbp-13 · Randomized controlled trial(s) · three-arm parallel randomized controlled trial · n = 66
    The consumption of chia seeds was associated with a reduction in diastolic blood pressure (change from baseline mean: 8.4 mmHg) compared to the other two groups.
    
    Who: adults with moderate hypertriglyceridemia on a low-calorie diet, alone, with 30 g/day chia or with fish oil, 22 per group
    Effect: DBP change from baseline -8.4 mmHg in the chia group, greater than the other two groups
    Certainty: Small; blood pressure was a secondary outcome.
    J Hum Nutr Diet, 2024 · checked 2026-10-07 · we read the abstract
14. ev-chbp-14 · Position of an expert body · scientific opinion of the EFSA NDA Panel (novel food safety assessment) · n = 2 case reports
    The information available indicates that allergic reactions upon consumption of chia seeds may occur.
    
    Who: consumers of chia seeds; case reports from Spain
    Effect: IgE-mediated anaphylaxis and eczema reported; prevalence of chia allergy unknown
    Certainty: Case reports only; no prevalence data.
    EFSA Journal, 2019, Safety of chia seeds (Salvia hispanica L.) as a novel food for extended uses pursuant to Regulation (EU) 2015/2283 · checked 2026-10-07 · we read the fulltext
15. ev-chbp-15 · Position of an expert body · scientific opinion of the EFSA NDA Panel (novel food safety assessment) · n = studies of 10 to 77 participants
    The Panel notes that no changes were found in the studied safety-related parameters and no adverse events related to the consumption of chia seeds were reported.
    
    Who: adults in human studies of chia seeds reviewed by EFSA, up to 50 g/day for up to 6 months
    Effect: no changes in safety-related parameters and no chia-related adverse events reported
    Certainty: The trials were not designed for safety and covered few safety endpoints.
    EFSA Journal, 2019, Safety of chia seeds (Salvia hispanica L.) as a novel food for extended uses pursuant to Regulation (EU) 2015/2283 · checked 2026-10-07 · we read the fulltext
16. ev-chbp-16 · Laboratory or animal data · case report · n = 1
    Diet included six tablespoons of chia seeds and five handfuls of almonds daily to manage IBS symptoms.
    
    Who: 59-year-old woman with controlled hypertension managing IBS symptoms by diet
    Effect: creatinine rose from 1.3 to 1.8 mg/dL; biopsy showed calcium oxalate deposition; improved on a low-oxalate diet
    Certainty: Single case; almonds contributed; dose far above usual 1 to 2 tablespoons.
    BMJ Case Rep, 2020 · checked 2026-10-07 · we read the abstract