Vitamin C supplements during ≥6 weeks reduce blood pressure

Objectives:
Vitamin C as a supplement to treat hypertension has been proposed. However, it remains controversial whether vitamin C can improve blood pressure in patients with primary hypertension. Therefore, this review article has been conducted.

Do vitamin C supplements reduce blood pressure in patients with primary hypertension?

Study design:
This review article included 8 RCTs involving 614 participants.
There was no publication bias.

Results and conclusions:
The investigators found vitamin C supplements significantly reduced systolic blood pressure in patients with essential hypertension [WMD  = -4.09, 95% CI = -5.56 to -2.62, p 0 .001, I2  =  35%, p = 0.15].

The investigators found vitamin C supplements significantly reduced diastolic blood pressure in patients with essential hypertension [WMD  = -2.30, 95% CI = -4.27 to -0.331, p  = 0 .02, I2 = 75%, p = 0 .0002].

The investigators found vitamin C supplements significantly reduced systolic blood pressure for the subgroup with an age ≥60 years and that with ≥35 participants [WMD = -3.75, 95% CI = -6.24 to -1.26, p  = 0 .003].

The investigators found vitamin C supplements significantly reduced diastolic blood pressure for the subgroup with an age ≥60 years and that with ≥35 participants [WMD = -3.29, 95% CI = -5.98 to -0.60, p  = 0 .02].

The investigators found in the subgroup analysis that vitamin C supplements during ≥6 weeks significantly reduced systolic blood pressure in patients with essential hypertension [WMD = -4.77, 95% CI = -6.46 to -3.08, p   0 .001].

The investigators found in the subgroup analysis that ≥500 mg/d vitamin C supplements significantly reduced systolic blood pressure in patients with essential hypertension [WMD  =  -5.01, 95% CI = -8.55 to -1.48, p  = 0.005, I2  =  44%, p =  0.13].

The investigators concluded ≥500 mg/d vitamin C supplements during ≥6 weeks reduce blood pressure in patients with primary hypertension. However, in view of the current level of evidence, large-scale trials should be conducted and attention should be paid to the evaluation of blood pressure variability.

Original title:
Effects of vitamin C supplementation on essential hypertension: A systematic review and meta-analysis by Guan Y, Dai P and Wang H.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7034722/

Additional information of El Mondo:
Find more information/studies on lowering of blood pressure, vitamin C and cardiovascular disease right here.