New evidence
Vitamin C lowered systolic blood pressure in a meta-analysis of 1,425 people with type 2 diabetes — but only when taken alone or with vitamin E, not with E alone.
This is a moderate-strength signal from four studies, all pointing in the same direction, but until more trials confirm it in non-diabetic populations and settle the dose, it's early evidence — not a prescription.
In people with type 2 diabetes, vitamin C — either by itself or combined with vitamin E — produced a significant drop in systolic blood pressure, according to a meta-analysis of 1,425 participants. The same analysis found that only the C+E combo also raised HDL ('good') cholesterol, while neither supplement alone improved HDL. Because the studies were in a clinical population and the dose wasn't specified, the effect may not apply to healthy people or casual supplement users.
Where this fits in the evidence
Pillser has synthesized 4 studies on Vitamin C for Reduced Systolic Blood Pressure — overall evidence strength: Moderate.
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.
The study
- Meta-Analysis
- n = 1,425
- 2025-08-05
- Nutrition reviews
- PubMed: 41521729
- DOI: 10.1093/nutrit/nuaf133
- Full study breakdown →
This is a plain-language summary of a research finding, not medical advice. Pillser surfaces research signals to help you decide what's worth investigating — always consult a qualified professional before changing what you take.