Best Supplements for Reduced Diastolic Blood Pressure
Ranked by research evidence. Compare 98 supplements across 143 papers from the biomedical literature, with effect direction, evidence strength, and dose range for each.
Top picks by evidence
- Moderate evidence4 studies
Across 4 studies, all reported beneficial effects of red grape extract (primarily grape seed extract) on reducing diastolic blood pressure, with predominantly small effect sizes. The median study duration was 34 days (range: 7–60 days), and the most studied dose was 520 mg/day in one trial, though dosing varied across studies. Evidence primarily comes from hypertensive or metabolic syndrome populations.
Dose: 520 mg/day (single dose reported; other studies did not specify dose) - Moderate evidence4 studies
Across 4 studies (3 beneficial, 1 neutral), flaxseed supplementation shows moderate evidence for a small-to-moderate reduction in diastolic blood pressure, primarily in clinical populations with type 2 diabetes, metabolic diseases, or hypertension. Three of four studies reported statistically significant reductions, with effect sizes ranging from small to moderate (e.g., weighted mean differences of -2.50 to -4.87 mmHg). No consistent dose or form was reported across studies.
- Moderate evidence3 studies
Across all 3 studies, spirulina supplementation was consistently associated with beneficial moderate-sized reductions in diastolic blood pressure. Two meta-analyses reported reductions of approximately -2.84 mmHg and -3.09 mmHg, and a systematic review reported a moderate effect size (g = -0.73). The most studied population was overweight and obese adults, though other meta-analyses included general healthy adults over 18 years.
98 supplements
- ModerateRed GrapeAcross 4 studies, all reported beneficial effects of red grape extract (primarily grape seed extract) on reducing diastolic blood pressure, with predominantly small effect sizes. The median study duration was 34 days (range: 7–60 days), and the most studied dose was 520 mg/day in one trial, though dosing varied across studies. Evidence primarily comes from hypertensive or metabolic syndrome populations. · Dose: 520 mg/day (single dose reported; other studies did not specify dose)4 beneficial4 studies
- ModerateflaxseedAcross 4 studies (3 beneficial, 1 neutral), flaxseed supplementation shows moderate evidence for a small-to-moderate reduction in diastolic blood pressure, primarily in clinical populations with type 2 diabetes, metabolic diseases, or hypertension. Three of four studies reported statistically significant reductions, with effect sizes ranging from small to moderate (e.g., weighted mean differences of -2.50 to -4.87 mmHg). No consistent dose or form was reported across studies.3 beneficial1 neutral4 studies
- ModerateSpirulinaAcross all 3 studies, spirulina supplementation was consistently associated with beneficial moderate-sized reductions in diastolic blood pressure. Two meta-analyses reported reductions of approximately -2.84 mmHg and -3.09 mmHg, and a systematic review reported a moderate effect size (g = -0.73). The most studied population was overweight and obese adults, though other meta-analyses included general healthy adults over 18 years.3 beneficial3 studies
- ModerateMoringaAcross 3 studies, all reported statistically significant beneficial effects of Moringa on diastolic blood pressure. One meta-analysis found a moderate reduction (SMD -0.41, 95% CI -0.75 to -0.07), while two systematic reviews reported larger reductions (mean difference -6.82 to -7.32 mmHg). The evidence base is small and overwhelmingly positive, which may reflect publication bias; no consistent dose or form data were reported.3 beneficial3 studies
- LowBlack CuminAcross 3 studies, all reported beneficial effects of Black Cumin (Nigella sativa) on reducing diastolic blood pressure, with effect sizes ranging from small to moderate. The most robust evidence comes from two large meta-analyses, one of which found a small but statistically significant reduction (WMD = -2.75 mmHg). Effects were typically observed over 4–8 weeks, with doses spanning 200–4600 mg/day, though the evidence base is small (only 3 studies). · Dose: 200 to 4600 mg/day3 beneficial3 studies
- LowL-CitrullineAcross 4 studies, 2 reported beneficial effects of L-citrulline on diastolic blood pressure, with effect sizes ranging from small to moderate, while 2 found neutral effects. The median study duration was 28 days (4 weeks), and the most-studied population was older adults (including middle-aged and elderly individuals). Doses ranged from 6 g/day to 10 g/day, though no single form was consistently used across studies. · Dose: 6-10 g/day2 beneficial2 neutral4 studies
- LowBeetrootAcross 3 studies, 2 reported beneficial effects on diastolic blood pressure, with effect sizes ranging from small to moderate. A large meta-analysis (75 RCTs, 1823 participants) found a small but significant dose-dependent reduction in diastolic BP (WMD: -0.12 mmHg per mmol increase in nitrate intake), and a smaller RCT (15 healthy males) observed a moderate reduction (mean -6 mmHg) with 140 ml nitrate-rich beetroot juice. One meta-analysis in adults with obesity found no significant effect, suggesting benefits may vary by population. · Dose: 140 ml nitrate-rich beetroot juice (~14.0 mmol nitrate) per dose, with dose-response effects observed from 0.12 mmHg reduction per mmol increase in nitrate intake2 beneficial1 neutral3 studies
- LowVitamin CAcross 3 studies, 2 reported beneficial effects of vitamin C on diastolic blood pressure, with effect sizes ranging from small to large. The median study duration was 40 days, suggesting effects may emerge over several weeks. The most prominent beneficial effect was observed in a meta-analysis of adults with diabetes, while evidence in young healthy adults was neutral.2 beneficial1 neutral3 studies
- LowFlaxAcross 3 studies, 1 reported a moderate beneficial effect of flaxseed oil on diastolic blood pressure (DBP) in adults with metabolic syndrome, while 2 meta-analyses found no significant effect in broader populations. The beneficial study used 25 mL/day of flaxseed oil for 49 days, but the aggregate evidence is predominantly neutral with small effect sizes. Median study duration was 49 days, though only 1 study reported duration. · Dose: 25 mL/day (from the single beneficial study)1 beneficial2 neutral3 studies
- LowFenugreek SeedAcross 3 studies, 1 reported a beneficial small effect of fenugreek seed supplementation on diastolic blood pressure, while 2 found neutral effects. The only statistically significant finding (p < 0.001) came from a small RCT in Alzheimer's patients using 5 cc of fenugreek seed extract over 120 days, while a meta-analysis and another RCT found no significant reduction. Evidence is limited and mixed, with no clear convergence on dose or population, and the median study duration was 88 days across two studies.1 beneficial2 neutral3 studies
- LowL-ArginineAcross 3 studies, 1 reported a beneficial moderate-sized effect of L-arginine (in combination with L-citrulline) on reducing diastolic blood pressure in middle-aged and elderly individuals, while 2 studies (including a systematic review in high-risk pregnancies and an RCT in healthy adults) found neutral small or nonsignificant effects. The overall evidence base is small and preliminary, and the beneficial finding came from a meta-analysis of combined supplementation rather than L-arginine alone.1 beneficial2 neutral3 studies
- LowavocadoAcross 3 studies, 1 reported a small beneficial effect on diastolic blood pressure, while 2 found neutral effects. The predominant effect size was small. Most studies used a dose of 1 avocado daily, and the median study duration was 101 days (approximately 14 weeks). The evidence is limited to clinical populations such as adults with abdominal obesity or elevated triglycerides. · Dose: 1 avocado per day (approximately 180 g)1 beneficial2 neutral3 studies
- Very lowblueberryAcross 3 studies, 1 reported a beneficial small effect on reduced diastolic blood pressure, while 2 found neutral effects. The single beneficial study was a systematic review and meta-analysis showing a statistically significant reduction of -2.20 mm Hg (95% CI: -4.13, -0.27). Effects were predominantly small in magnitude, and the evidence base is too limited to identify a clear dose range or population.1 beneficial2 neutral3 studies