Best Supplements for Reduced Systolic Blood Pressure
Ranked by research evidence. Compare 104 supplements across 150 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 vitamin C on reducing systolic blood pressure, with a predominant moderate effect size. Two meta-analyses (the highest-quality evidence) found significant reductions, including an estimated 3.7 mmHg decrease in adults and benefits in individuals with type 2 diabetes. Studies ranged from 40 days in one trial to meta-analyses without specified durations, with a median study duration of 40 days, suggesting effects may appear within weeks.
- Moderate evidence3 studies
Across all 3 studies, all reported beneficial effects of beetroot on reducing systolic blood pressure, with effect sizes ranging from small to moderate. The most robust evidence comes from a large meta-analysis (75 RCTs, 1823 participants) showing a small but statistically significant dose-dependent reduction in systolic BP per mmol increase in nitrate intake. Most studies did not consistently report a specific form, but one study used beetroot juice (140 ml, ~14 mmol nitrate).
Dose: per mmol increase in administered nitrate; ~14 mmol/day in juice form - Moderate evidence3 studies
Across 3 studies, all reported beneficial effects on reduced systolic blood pressure, with effect sizes ranging from small to moderate. The evidence is supported by two large meta-analyses (including one with 82 RCTs) showing small but statistically significant reductions (e.g., WMD = -3.25 mmHg). Most studies used doses of 200–4600 mg/day of Nigella sativa (black cumin), and the median study duration was 32 days, suggesting effects may be observed within 4–8 weeks.
Dose: 200–4600 mg/day
104 supplements
- ModerateVitamin CAcross 4 studies, all reported beneficial effects of vitamin C on reducing systolic blood pressure, with a predominant moderate effect size. Two meta-analyses (the highest-quality evidence) found significant reductions, including an estimated 3.7 mmHg decrease in adults and benefits in individuals with type 2 diabetes. Studies ranged from 40 days in one trial to meta-analyses without specified durations, with a median study duration of 40 days, suggesting effects may appear within weeks.4 beneficial4 studies
- LowflaxseedAcross 4 studies (all meta-analyses or reviews), 3 reported moderate beneficial reductions in systolic blood pressure, while 1 high-quality meta-analysis in type 2 diabetes patients found a neutral small effect. The predominant effect size among beneficial studies was moderate. Evidence is limited by small number of studies and inconsistency between the highest-quality study and lower-quality reviews.3 beneficial1 neutral4 studies
- ModerateBeetrootAcross all 3 studies, all reported beneficial effects of beetroot on reducing systolic blood pressure, with effect sizes ranging from small to moderate. The most robust evidence comes from a large meta-analysis (75 RCTs, 1823 participants) showing a small but statistically significant dose-dependent reduction in systolic BP per mmol increase in nitrate intake. Most studies did not consistently report a specific form, but one study used beetroot juice (140 ml, ~14 mmol nitrate). · Dose: per mmol increase in administered nitrate; ~14 mmol/day in juice form3 beneficial3 studies
- ModerateBlack CuminAcross 3 studies, all reported beneficial effects on reduced systolic blood pressure, with effect sizes ranging from small to moderate. The evidence is supported by two large meta-analyses (including one with 82 RCTs) showing small but statistically significant reductions (e.g., WMD = -3.25 mmHg). Most studies used doses of 200–4600 mg/day of Nigella sativa (black cumin), and the median study duration was 32 days, suggesting effects may be observed within 4–8 weeks. · Dose: 200–4600 mg/day3 beneficial3 studies
- LowL-ArginineAcross 4 studies, 2 reported beneficial effects of L-arginine on reducing systolic blood pressure, while 2 found neutral results. The beneficial effects ranged from small to large, with a moderate effect observed in one meta-analysis (SBP reduction of -5.64 mmHg) among pregnant women. The most-studied populations were pregnant women and older adults, but doses and forms were poorly reported, limiting convergence on an effective dose range.2 beneficial2 neutral4 studies
- LowRed GrapeAcross 4 studies, 2 reported beneficial small effects and 2 reported neutral small effects on systolic blood pressure. The beneficial findings come from a systematic review and an RCT in NAFLD patients, while a short-term RCT and a meta-analysis showed no significant effect. The median study duration was 34 days (range 7–60 days), and the most common dose was 520 mg/day of grape seed extract. · Dose: 520 mg/day2 beneficial2 neutral4 studies
- ModerateFenugreek SeedAcross 3 studies, 2 reported small beneficial effects of fenugreek seed supplementation on reducing systolic blood pressure, with a meta-analysis (2023) showing a significant reduction (WMD: 3.46 mmHg). The third study found no significant between-group difference. Effects were typically observed at 12-14 weeks. The most-studied dose range is around 5-15 g/day of fenugreek seed. · Dose: 5-15 g/day2 beneficial1 neutral3 studies
- LowavocadoAcross 3 studies, 2 reported beneficial small-sized effects of avocado on reducing systolic blood pressure, while 1 found a neutral effect. The sole meta-analysis showed a statistically significant but small reduction (-1.15 mmHg). The most-studied dose was 1 avocado daily, and effects were observed in clinical populations (adults with abdominal obesity or elevated triglycerides). The median study duration was 101 days, suggesting effects are typically observed after several weeks to months. · Dose: 1 avocado daily2 beneficial1 neutral3 studies
- LowHibiscusAcross 3 studies, 2 reported beneficial effects (one moderate, one large) of hibiscus on reducing systolic blood pressure, while 1 meta-analysis found neutral effects in patients with metabolic syndrome. Evidence suggests benefit is most pronounced in hypertensive individuals over 50 years of age, with effects typically observed at 4+ weeks. The median study duration was 104 days across two studies that reported duration, and the most studied doses were 10 g/day as a brew or 2×375 mg/day as tablets. · Dose: 10 g/day (brew) or 2×375 mg/day (tablets)2 beneficial1 neutral3 studies
- LowVitamin DAcross 3 studies, 2 reported beneficial small-to-moderate effects of vitamin D supplementation on reducing systolic blood pressure, while 1 found no significant association. The most notable benefit was observed in a 2025 meta-analysis showing a small but significant reduction (MD: -2.83 mmHg, 95% CI [-5.47, -0.199], P=0.04). One review reported moderate beneficial effects specifically in obese youths with baseline vitamin D deficiency (<20 ng/mL). Dose and form data were inconsistently reported, though one study used 4,000 IU/day. · Dose: 4,000 IU/day2 beneficial1 neutral3 studies
- LowFlaxAcross 3 studies, 2 reported beneficial effects of flax on reducing systolic blood pressure, while 1 found a neutral effect. The effect sizes were mixed (small to large), with the largest effect observed in a 49-day trial using 25 mL/day flaxseed oil in patients with metabolic syndrome. The median study duration was 49 days, suggesting effects may be observed after 7 weeks of supplementation. · Dose: 25 mL/day2 beneficial1 neutral3 studies
- LowHesperidinAcross 3 meta-analyses, 2 reported beneficial effects of hesperidin on systolic blood pressure, while 1 reported a neutral effect. The beneficial effects were small to moderate in magnitude, with significant reductions observed in patients with type 2 diabetes (WMD = -4.32 mmHg, 95% CI: -7.77 to -0.87) and in adults ingesting doses exceeding 500 mg/day. Evidence in the general clinical population is mixed, with one large meta-analysis (n=2414) finding no significant effect (IV: -0.29, 95% CI: -2.21 to 1.63, p=0.77). · Dose: exceeding 500 mg/day2 beneficial1 neutral3 studies
- ModerateL-CarnitineAcross 3 studies, all reported neutral effects of L-carnitine on systolic blood pressure, with small effect sizes and no statistically significant findings. The evidence includes a meta-analysis of 1,412 adults and two smaller clinical studies (metabolically healthy women with obesity and hemodialysis patients). The median study duration was 56 days, but only one study specified a dose (L-carnitine-tartrate 1000 mg/day).3 neutral3 studies