Home Ingredients MegaNatural®-BP (Patented Grape Seed Extract — Polyphenolics)
Cardiovascular

MegaNatural®-BP (Patented Grape Seed Extract — Polyphenolics)

Vitis vinifera
Evidence Level
Limited
3 Clinical Trials
7 Documented Benefits
2/5 Evidence Score

MegaNatural-BP is a patented grape seed extract developed by Polyphenolics (division of California Natural Color and E. & J. Gallo Winery), distinguished from generic grape seed extracts by a unique structure and composition via a patented hot-water extraction process. Small placebo-controlled trials found a modest blood pressure reduction, but the largest trial (70 subjects, 8 weeks) found no significant effect, and in 2021 EFSA judged the evidence insufficient to establish that it maintains normal blood pressure. Blood pressure is a surrogate: no trial has measured heart attacks, strokes or mortality. FDA GRAS no-objection is a safety status, not proof of efficacy. Used for: blood pressure within the normal range.

Studied Dose 150-300 mg/day.
Active Compound Grape seed proanthocyanidins (>90%).

Benefits

Blood Pressure Within Normal Range — UC Davis Trials

Two small placebo-controlled trials found a blood pressure reduction: a metabolic syndrome trial (about 27 subjects, 4 weeks) reported roughly 12 mmHg systolic and 8 mmHg diastolic falls in the 300 mg group, and a prehypertension beverage trial (29 completers, 6 weeks) reported a 5.6% systolic and 4.7% diastolic reduction at 300 mg/day. A larger 8-week trial (70 subjects) found no significant change. The effect is on blood pressure only, a surrogate, with no data on cardiovascular events.

Supported by Trial 1, Trial 2

Mixed Results Across Three Trials

Two small trials found a blood pressure reduction and the largest trial (a different grape seed extract, 70 subjects) found none; EFSA judged the overall evidence insufficient.

Supported by Trial 3, Trial 1

Endothelial Function Not Improved

Trials that measured vascular function found no benefit: the prehypertension trial reported no change in flow-mediated dilation, and the largest trial found no change in vasoactive markers.

Supported by Trial 2, Trial 3

No Athletic Performance Evidence

No blood flow or athletic performance trial of MegaNatural-BP has been published; the trials on this ingredient measured blood pressure only.

Supported by Trial 1, Trial 2

Six-Week Onset

Clinical studies show benefits after just 6 weeks — practical timeline for consumer applications.

Supported by Trial 2

Patented Hot-Water Extraction

Distinctive manufacturing process produces unique structure and composition vs solvent-extracted generics.

Sustainable California Origin

Made in California from special seed blend from unfermented red and white wine grape seeds — sustainable byproduct upcycling from E. & J. Gallo Winery.

Supported by Trial 3, Trial 2

Mechanism of action

1

Proanthocyanidin (PAC) Vascular Effects

Grape seed proanthocyanidins enhance endothelial nitric oxide synthase (eNOS); improve vasodilation; modest BP effects.

2

Antioxidant ORAC Activity

>90% proanthocyanidin content provides high ORAC antioxidant capacity; quenches vascular reactive oxygen species.

3

ACE Inhibition (Modest)

Modest angiotensin-converting enzyme inhibition; relevant to BP effects.

4

Hot-Water Extraction Distinction

Polyphenolics' patented hot-water process produces specific PAC profile distinct from solvent-extracted alternatives.

5

Capillary Integrity

PACs support capillary integrity broadly relevant to vascular health.

Clinical trials

1
MegaNatural-BP for Metabolic Syndrome BP — UC Davis
PubMed

Placebo-controlled trial of MegaNatural-BP in metabolic syndrome patients at UC Davis Department of Preventative Cardiology.

Metabolic syndrome patients with elevated BP.

In the small trial's 300 mg group, systolic and diastolic blood pressure fell significantly versus placebo, by roughly 12 and 8 mmHg over 4 weeks; the sample was small (about 27 subjects across three arms).

2
MegaNatural-BP for Prehypertension — UC Davis
PubMed

Randomised placebo-controlled trial of a 300 mg/day grape seed extract beverage for 6 weeks in prehypertensive adults (Br J Nutr 2016); 36 randomised, 29 completed.

Prehypertensive adults.

Systolic blood pressure fell 5.6% and diastolic 4.7% after 6 weeks versus placebo, reverting after washout; flow-mediated dilation, lipids, glucose and oxidised LDL were unchanged.

3
Grape Seed Extract, No BP Effect (Unilever, Br J Nutr 2013)
PubMed

Largest and best-controlled trial: 70 adults, 8 weeks, 300 mg/day of a low-molecular-weight grape seed extract made by Unilever (not MegaNatural-BP), measuring ambulatory blood pressure.

Pre- and stage I hypertensive adults.

No significant effect: systolic blood pressure fell 3.0 mmHg and diastolic 1.4 mmHg versus placebo, neither statistically significant, and vasoactive markers and platelet aggregation were unchanged.

Side effects and drug interactions

Common Potential side effects

Generally well-tolerated.
Mild GI distress (rare).
Allergic reactions to grape rare.
Theoretical bleeding effects from PACs at very high doses.
Self-affirmed GRAS / FDA no-objection.

Important Drug interactions

Antihypertensives — additive BP-lowering effects; consult; modest concern.
Anticoagulants — modest antiplatelet effects.
Diabetes medications — modest hypoglycemic effects.
Pre-surgery — discontinue 1-2 weeks before for bleeding risk.
Pregnancy — culinary grape safe; concentrated supplementation limited specific data.
Lactation — generally safe.
Cyclosporine — theoretical interactions with grape products; consult.
Vitamin C — synergistic antioxidant effects.

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Frequently asked questions about MegaNatural®-BP (Patented Grape Seed Extract — Polyphenolics)

What is MegaNatural-BP?

MegaNatural-BP is a patented grape seed extract developed by Polyphenolics (division of California Natural Color and E. & J. Gallo Winery), distinguished from generic grape seed extracts by a unique structure and composition via a patented hot-water extraction process.

What is MegaNatural-BP used for?

MegaNatural-BP is researched primarily for Cardiovascular. Two small placebo-controlled trials found a blood pressure reduction: a metabolic syndrome trial (about 27 subjects, 4 weeks) reported roughly 12 mmHg systolic and 8 mmHg diastolic falls in the 300 mg group, and a prehypertension beverage t…

What is the recommended dosage of MegaNatural-BP?

The clinically studied dose is 150-300 mg/day. Always follow the product label and check with a healthcare provider for personal advice.

Is MegaNatural-BP safe, and does it have side effects?

For most healthy adults, MegaNatural-BP is well tolerated at studied doses. Reported effects can include: Generally well-tolerated. Mild GI distress (rare). It may also interact with some medications. MegaNatural-BP is not right for everyone, so check with a healthcare provider first if you are pregnant or breastfeeding, have a medical condition, or take prescription medication.

Does MegaNatural-BP interact with any medications?

Possible interactions include: Antihypertensives — additive BP-lowering effects; consult; modest concern. Anticoagulants — modest antiplatelet effects. If you take prescription medication, check with a pharmacist or doctor before using it.

How strong is the scientific evidence for MegaNatural-BP?

NutraSmarts rates the evidence for MegaNatural-BP as Limited (2 out of 5). It is backed by 3 clinical trials and 4 cited references summarized on this page. A higher rating reflects more, larger, and better-designed human studies.

References(4 citations)

Evidence ratings on NutraSmarts are based on the totality of human clinical research, with emphasis on randomized controlled trials, meta-analyses, and systematic reviews. The references below directly support claims made throughout this page.

  1. Sivaprakasapillai B, Edirisinghe I, Randolph J, Steinberg F, Kappagoda T. Effect of grape seed extract on blood pressure in subjects with the metabolic syndrome. Metabolism. 2009;58(12):1743-6. doi: 10.1016/j.metabol.2009.05.030.PubMedUsed to support: Brand-specific (MegaNatural-BP grape-seed extract) RCT in metabolic-syndrome subjects: 150 and 300 mg/d for 4 weeks lowered both systolic and diastolic BP vs placebo, with no change in serum lipids or glucose. Small, short-duration trial.
  2. Park E, Edirisinghe I, Choy YY, Waterhouse A, Burton-Freeman B. Effects of grape seed extract beverage on blood pressure and metabolic indices in individuals with pre-hypertension: a randomised, double-blinded, two-arm, parallel, placebo-controlled trial. Br J Nutr. 2016;115(2):226-38. doi: 10.1017/S0007114515004328.PubMedUsed to support: Prehypertension RCT of a 300 mg/day grape seed extract beverage for 6 weeks (36 randomised, 29 completed); the PubMed abstract does not state the brand, though EFSA treated this as MegaNatural-BP evidence. Systolic BP fell 5.6% and diastolic 4.7% versus placebo, reverting after a 4-week washout. Flow-mediated dilation, fasting lipids, glucose and oxidised LDL were unchanged. Small sample with notable dropout in the extract arm.
  3. Ras RT, Zock PL, Zebregs YE, Johnston NR, Webb DJ, Draijer R. Effect of polyphenol-rich grape seed extract on ambulatory blood pressure in subjects with pre- and stage I hypertension. Br J Nutr. 2013;.PubMedUsed to support: Largest grape seed extract blood pressure trial: 70 adults with pre- and stage I hypertension, 300 mg/day for 8 weeks, using a low-molecular-weight grape seed extract from Unilever (not MegaNatural-BP). Ambulatory blood pressure was not significantly changed (systolic -3.0 mmHg, diastolic -1.4 mmHg, both non-significant), and vasoactive markers and platelet aggregation were unaffected.
  4. EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA). MegaNatural(R)-BP grape seed extract and maintenance of normal blood pressure: evaluation of a health claim pursuant to Article 13(5) of Regulation (EC) No 1924/2006. EFSA J. 2021;.PubMedUsed to support: European Food Safety Authority opinion on a health claim for MegaNatural-BP and maintenance of normal blood pressure. Of two eligible human trials, one (300 mg/day, 6 weeks) showed an effect and one (300 mg/day, 8 weeks) did not; no plausible mechanism was established. EFSA concluded the evidence is insufficient to establish a cause and effect relationship between MegaNatural-BP and maintenance of normal blood pressure.