Reducing levels of C-Reactive Protein: An eight-week, open-label clinical trial of three oral supplements

Abstract

C-reactive protein (CRP) is a protein in the blood that increases with inflammation, and high CRP levels measured with high-sensitivity CRP (hs-CRP) tests can indicate higher risk of heart attack or stroke. Several over-the-counter oral supplements reduce CRP levels. This eight-week, open-label clinical trial investigated whether Vitamin C, ginger, or curcumin were most effective at reducing hs-CRP levels in healthy individuals with low baseline hs-CRP levels. Thirty healthy male and female participants were enrolled in one of three trial treatment arms: Vitamin C (1000 mg/day), ginger (2000 mg/day), and curcumin (1000 mg/day). hs-CRP levels were collected at baseline and after eight weeks of oral supplements. Paired t-tests were used to analyze data by age, body mass index (BMI), and baseline hs-CRP level. The primary outcome measure was mean difference between time points and 95% confidence intervals. Twenty-six people completed the study. Baseline hs-CRP levels were very low for all three intervention groups. Based on estimated mean difference, all three supplements reduced hs-CRP levels, but change at eight weeks was not statistically significant. Within the groups, ginger most consistently reduced hs-CRP levels even though the ginger group had the lowest mean baseline hs-CRP levels. Curcumin was least likely to reduce hs-CRP levels. Overall, all three interventions reduced hs-CRP levels in this group of healthy participants with low baseline levels, suggesting that these agents, which are available over-the-counter, may provide an alternative for reducing inflammation. Larger clinical trials to assess the utility of these agents are warranted.