Best Supplements for Reduced Systolic Blood Pressure
Ranked by research evidence. Compare 114 supplements across 184 papers from the biomedical literature, with effect direction, evidence strength, and dose range for each.
Top picks by evidence
- High evidence5 studies
Across 5 studies, all reported statistically significant beneficial effects of black cumin (Nigella sativa) supplementation on reducing systolic blood pressure. The predominant effect size was small, with meta-analyses showing a weighted mean difference of approximately -3 mmHg. Effects were typically observed at 8 weeks (median study duration 56 days), and doses ranged from 400 mg to 4600 mg per day, most commonly in patients with metabolic or cardiovascular conditions.
- Moderate evidence6 studies
Across 6 studies on red grape (grape seed extract) supplementation and reduced systolic blood pressure, 4 reported beneficial effects and 2 found neutral effects. The predominant effect size was small, with one study showing a moderate effect. Most evidence comes from small randomized controlled trials (RCTs) with median study duration of 34 days, and doses were inconsistently reported but included 300 mg and 520 mg/day in clinical populations such as NAFLD patients, prehypertensive men, and obese males.
Dose: 300–520 mg/day - Moderate evidence4 studies
Across 4 studies, all reported beneficial effects on reducing systolic blood pressure, with moderate effect sizes predominantly (3 moderate, 1 small). All 4 studies were statistically significant. Effects were observed in various populations including individuals with type 2 diabetes, general adults, young healthy adults, and heat-exposed workers. Only one study reported a dose (130 mg/day) and duration (40 days), limiting dose-response conclusions.
114 supplements
- HighBlack CuminAcross 5 studies, all reported statistically significant beneficial effects of black cumin (Nigella sativa) supplementation on reducing systolic blood pressure. The predominant effect size was small, with meta-analyses showing a weighted mean difference of approximately -3 mmHg. Effects were typically observed at 8 weeks (median study duration 56 days), and doses ranged from 400 mg to 4600 mg per day, most commonly in patients with metabolic or cardiovascular conditions.5 beneficial5 studies
- ModerateRed GrapeAcross 6 studies on red grape (grape seed extract) supplementation and reduced systolic blood pressure, 4 reported beneficial effects and 2 found neutral effects. The predominant effect size was small, with one study showing a moderate effect. Most evidence comes from small randomized controlled trials (RCTs) with median study duration of 34 days, and doses were inconsistently reported but included 300 mg and 520 mg/day in clinical populations such as NAFLD patients, prehypertensive men, and obese males. · Dose: 300–520 mg/day4 beneficial2 neutral6 studies
- ModerateVitamin CAcross 4 studies, all reported beneficial effects on reducing systolic blood pressure, with moderate effect sizes predominantly (3 moderate, 1 small). All 4 studies were statistically significant. Effects were observed in various populations including individuals with type 2 diabetes, general adults, young healthy adults, and heat-exposed workers. Only one study reported a dose (130 mg/day) and duration (40 days), limiting dose-response conclusions.4 beneficial4 studies
- Moderategreen teaAcross all 4 studies, green tea showed beneficial effects on systolic blood pressure, with predominantly small effect sizes (3 small, 1 large). The median study duration was 90 days (based on 1 study). Populations included healthy adults and those at high risk of cardiovascular disease, but doses varied widely across studies, making it difficult to identify a specific effective dose range.4 beneficial4 studies
- ModerateL-ArginineAcross 5 studies, 3 reported beneficial effects of L-arginine on systolic blood pressure, with effect sizes ranging from moderate to large (one moderate, one large, one moderate). The remaining 2 studies found neutral effects. Evidence is strongest for pregnant women and elderly populations, but results are mixed: a meta-analysis in pregnant women (2028 participants) showed a moderate reduction (MD -5.64 mmHg, very low certainty), while another systematic review in high-risk pregnancies found no statistically significant difference. One study in middle-aged/elderly individuals reported a large reduction (-10.44 mmHg) when combined with L-citrulline. Doses and durations were not consistently reported across studies.3 beneficial2 neutral5 studies
- ModerateHibiscusAcross 4 studies, 3 reported beneficial effects on reducing systolic blood pressure, with effect sizes ranging from small to large; one study found neutral results. The two strongest meta-analyses (2025 and 2022) both had evidence scores of 7, one showing moderate beneficial effects and the other showing small neutral effects, resulting in mixed overall effect sizes. The median study duration was 104 days, suggesting effects are typically observed over several months, though doses varied widely (e.g., 2×375 mg/day tablet or 10 g/day brew in one study).3 beneficial1 neutral4 studies
- LowflaxseedAcross 4 studies, 3 reported beneficial moderate-sized reductions in systolic blood pressure, but the highest-quality meta-analysis (n=1136, evidence score 7) found no significant effect (SMD 0.50; 95% CI: -1.25 to 0.25, p=0.193). The beneficial studies showed moderate reductions (WMD -4.30 to -8.64 mmHg) in clinical populations with metabolic diseases, type 2 diabetes, cardiovascular risk factors, or hypertension. No consistent dose or form was reported across studies.3 beneficial1 neutral4 studies
- ModerateBeetrootAcross 3 studies, all 3 reported statistically significant beneficial effects of beetroot supplementation on reducing systolic blood pressure. Effect sizes were mixed (small to moderate), with the largest meta-analysis showing a small dose-dependent reduction of -0.28 to -0.48 mmHg per mmol nitrate intake, while a small RCT observed a moderate reduction of -7 mmHg with 140 ml beetroot juice (~14.0 mmol nitrate). The evidence primarily comes from adults in clinical settings, with the most-studied form being beetroot juice. · Dose: per mmol nitrate intake to ~14.0 mmol/day3 beneficial3 studies
- ModerateLemon BalmAcross 3 studies, all reported beneficial effects on systolic blood pressure, with effect sizes ranging from moderate to large; the predominant effect size was moderate. Effects were observed after 28 days of supplementation in hypertensive populations. The evidence base is small but consistent.3 beneficial3 studies
- ModerateCocoaAll 3 studies report beneficial effects of cocoa flavanols on reducing systolic blood pressure, with effect sizes ranging from small to moderate. The most-studied dose is 500 mg twice daily, and effects have been observed over a median duration of 30 days. Evidence comes from one meta-analysis and two RCTs in older adults without cardiovascular disease. · Dose: 500 mg twice daily3 beneficial3 studies
- Very lowL-CitrullineAcross all 3 studies in the database, L-Citrulline supplementation was associated with beneficial reductions in systolic blood pressure, with effect sizes ranging from moderate to large. A 2025 meta-analysis reported a statistically significant large effect of -10.44 mmHg (95% CI: -13.57 to -7.31) in middle-aged and elderly individuals. However, the evidence base is very small (only 3 studies), and no consistent dose, form, or study duration data were reported across studies.3 beneficial3 studies
- ModerateResveratrolAcross 3 studies, 2 reported beneficial effects on systolic blood pressure, with effect sizes ranging from small to moderate. The evidence is primarily from clinical populations with type 2 diabetes or coronary artery disease, though one study (a single-dose acute trial) was neutral.2 beneficial1 neutral3 studies
- LowHesperidinAcross 3 meta-analyses, 2 reported beneficial effects of hesperidin on reducing systolic blood pressure, with effect sizes ranging from small to moderate, while 1 neutral study found no statistically significant change. The beneficial effects were most pronounced in patients with type 2 diabetes, with one meta-analysis reporting a moderate effect (WMD = -4.32 mmHg, p = 0.01). Doses exceeding 500 mg/day were associated with a significant but small reduction in systolic blood pressure in adults. · Dose: exceeding 500 mg/day2 beneficial1 neutral3 studies
- LowFlaxAcross 3 studies, 2 reported small beneficial effects of flaxseed oil on systolic blood pressure (SBP), while 1 meta-analysis found no significant effect. The beneficial effects were predominantly small in size, with one randomized controlled trial showing a large reduction (-14 mmHg) in patients with metabolic syndrome. The median study duration was 49 days, and the evidence base is too small to determine a clear dose range.2 beneficial1 neutral3 studies
- LowFenugreek SeedAcross 3 studies, 2 reported beneficial small effects on systolic blood pressure, while 1 found neutral between-group results. The predominant effect size is small. The most-studied dose is approximately 15 g/day of fenugreek seed. Median study duration is 88 days (about 12.6 weeks), indicating effects are typically observed at 8–12 weeks. Evidence is drawn from clinical populations including type 2 diabetes and Alzheimer's disease. · Dose: approximately 15 g/day (e.g., 5 g three times daily)2 beneficial1 neutral3 studies
- LowavocadoAcross 3 studies, 2 reported small beneficial effects on systolic blood pressure, while 1 reported a neutral effect. The most studied dose was 1 avocado daily. Effects were observed in clinical populations (abdominal obesity, elevated triglycerides) with a median study duration of 101 days. · Dose: 1 avocado daily2 beneficial1 neutral3 studies
- LowVitamin DAcross 3 studies, 2 reported beneficial small-to-moderate effects of vitamin D on reducing systolic blood pressure, while 1 found no significant effect. The largest meta-analysis (evidence score 4) showed a small but significant reduction (MD: -2.83 mmHg). Evidence is limited and mixed by study design and population, with no clear convergence on dose or form.2 beneficial1 neutral3 studies
- LowL-CarnitineAcross 4 studies, 3 reported neutral small-sized effects on systolic blood pressure, and 1 reported a beneficial small-sized effect. The only statistically significant finding was in a small RCT of β-thalassemia patients. The median study duration was 118 days (approx. 17 weeks), and the only specified dose was 1 g/day of L-carnitine tartrate in one study.1 beneficial3 neutral4 studies
- Lowchia seedAcross 3 studies, 1 reported a beneficial small effect on systolic blood pressure, while 2 found no significant effect. The only statistically significant finding came from a meta-analysis (2025) with a small effect size (g = -0.119). Effects were predominantly small across studies, and the median study duration was 84 days (reported by only 1 study).1 beneficial2 neutral3 studies