Effects of Curcumin Intake on CVD Risk Factors and Exercise-Induced Oxidative Stress in Healthy Volunteers—An Exploratory Study

Abstract

Background: Evidence suggests that turmeric or curcumin intake can improve antioxidant defense, blood pressure, ageing and gut microbiota. The effects of turmeric concentrate (curcumin) intake on cardiovascular risk factors and exercise-induced oxidative stress were investigated. Methods: A randomized placebo-controlled study was performed to assess the effects of turmeric extract in healthy volunteers before and after a 30-minute exercise bout. Participants (n = 22) were given either 500 mg turmeric concentrate (Curcumin C3, Jarrow Formulas, Los Angeles, CA, USA) or placebo supplements. Anthropometry, systolic and diastolic blood pressure (SBP and DBP), pulse wave velocity (PWV), biomarkers of oxidative stress, perceived exertion and lipid peroxidation were assessed. Results: There were no significant differences in all baseline parameters between the placebo and the curcumin groups (p > 0.05). In the curcumin group, blood pressure response to exercise following curcumin intake was blunted, and the increase was not significant compared to basal values. In the last run, there was a significant difference (before–after) between curcumin and placebo groups (Δ in SBP: 7.3 ± 6.8 vs. 13.8 ± 6.3 mmHg, p = 0.007, and Δ in DBP: 2.3 ± 6.9 V 8.0 ± 6.8 mmHg, p = 0.012). Final PWV scores were reduced significantly in the curcumin group (7.2 ± 0.97 to 6.7 ± 0.77 m/s, p = 0.033), and this reduction was significant compared to the control (Δ of 0.56 vs. 0.21 m/s, p = 0.04). A significant increase was observed in urinary antioxidant power (p = 0.031) and total polyphenol levels (p = 0.022) post curcumin intervention, and those in the placebo did not show significant changes. The increase in exercise-induced MDA levels was blunted only in the curcumin group, and the before–after difference was significant compared to the control (Δ of −0.81 vs. +0.205 μmole/day, p = 0.032). The distance ran by the participants taking curcumin was significantly longer (p = 0.005), and compared to the placebo, the before–after difference was significant (Δ of −0.69 vs. +0.28 km, p = 0.014). Conclusion: Our study suggests that turmeric concentrate intake can reduce blood pressure and improve antioxidant, anti-inflammatory status and arterial compliance. Curcumin may improve exercise performance and ameliorate oxidative stress. Larger studies are warranted to validate these findings and test other cardiovascular risk factors.