Cocoa may benefit heart health
MedWire News: Cocoa consumption may improve cardiovascular (CV) and metabolic health, suggest findings of a systematic review and meta-analysis of randomized controlled trials.
The analysis of 24 studies, involving 1106 participants, showed that consumption of flavonoid-rich cocoa (FRC) significantly improves blood pressure, circulating lipid levels, insulin resistance, and flow-mediated vascular dilation (FMD), without exerting an effect on circulating C-reactive protein (CRP) or triglyceride levels.
Many previous studies have suggested that foods rich in plant-derived polyphenolic compounds have cardioprotective effects, explain Eric Ding (Harvard Medical School, Boston, Massachusetts, USA) and co-authors. However, none have examined the role of FRCs specifically on all major CV risk factors, they say.
"We undertook a systematic review and meta-analysis of randomized, controlled trials performed in adults to examine the effects of FRC on multiple markers of CV health and to determine whether a dose-response curve exists between FRC intake and these outcomes."
As reported in The Journal of Nutrition, cocoa consumption decreased mean low-density lipoprotein (LDL) cholesterol levels by 0.077 mmol/l (2.97 mg/dl) and systolic blood pressure by 1.63 mmHg, while mean levels of high-density lipoprotein (HDL) cholesterol increased by 0.046 mmol/l (1.78 mg/dl). Levels of total cholesterol, triglycerides, and CRP were not affected by FRC consumption.
Furthermore, insulin resistance significantly decreased in response to cocoa consumption, demonstrated by a decrease in the homeostasis model assessment of insulin resistance of 0.94 points, while FMD increased by 1.53%.
Ding et al found a nonlinear dose-response relationship between FRC and FMD, with FMD increasing as the dose approached 500 mg and decreasing at higher doses. A similar, but nonsignificant, pattern was seen with HDL cholesterol, notes the team.
Subgroup analysis revealed that the impact of cocoa consumption on both total and LDL cholesterol was significantly modified by the participant's age; patients older than 50 years did not gain the same benefit as younger patients.
"Further study is warranted to determine whether these findings translate to an improvement in adverse cardiovascular outcomes," conclude the authors.
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By Nikki Withers