06.01.12
Nutraceutical: Vitamin C
Indication: Blood pressure
Source: Am J Clin Nutr, May 2012;95(5):1079-88.
Research: In observational studies, increased vitamin C intake, vitamin C supplementation and higher blood concentrations of vitamin C are associated with lower blood pressure (BP). However, evidence for blood pressure-lowering effects of vitamin C in clinical trials is inconsistent. The objective of this study was to conduct a systematic review and meta-analysis of clinical trials that examined the effects of vitamin C supplementation on BP. Researchers searched Medline, EMBASE and Central databases from 1966 to 2011. Pre-specified inclusion criteria were: 1) use of a randomized controlled trial design; 2) trial reported effects on systolic BP (SBP) or diastolic BP (DBP) or both; 3) trial used oral vitamin C and concurrent control groups; and 4) trial had a minimum duration of 2 weeks.
Results: Twenty-nine trials met eligibility criteria for the primary analysis. The median dose was 500 mg/day, the median duration was 8 weeks, and trial sizes ranged from 10 to 120 participants. In short-term trials, vitamin C supplementation reduced SBP and DBP. However, long-term trials on the effects of vitamin C supplementation on BP and clinical events are needed.
Indication: Blood pressure
Source: Am J Clin Nutr, May 2012;95(5):1079-88.
Research: In observational studies, increased vitamin C intake, vitamin C supplementation and higher blood concentrations of vitamin C are associated with lower blood pressure (BP). However, evidence for blood pressure-lowering effects of vitamin C in clinical trials is inconsistent. The objective of this study was to conduct a systematic review and meta-analysis of clinical trials that examined the effects of vitamin C supplementation on BP. Researchers searched Medline, EMBASE and Central databases from 1966 to 2011. Pre-specified inclusion criteria were: 1) use of a randomized controlled trial design; 2) trial reported effects on systolic BP (SBP) or diastolic BP (DBP) or both; 3) trial used oral vitamin C and concurrent control groups; and 4) trial had a minimum duration of 2 weeks.
Results: Twenty-nine trials met eligibility criteria for the primary analysis. The median dose was 500 mg/day, the median duration was 8 weeks, and trial sizes ranged from 10 to 120 participants. In short-term trials, vitamin C supplementation reduced SBP and DBP. However, long-term trials on the effects of vitamin C supplementation on BP and clinical events are needed.