Dark chocolate attenuates intracellular pro-inflammatory reactivity to acute psychosocial stress in men: A randomized controlled trial

Abstract

Flavanol-rich dark chocolate consumption relates to lower risk of cardiovascular mortality, but underlying mechanisms are elusive. We investigated the effect of acute dark chocolate consumption on inflammatory measures before and after stress. Healthy men, aged 20-50years, were randomly assigned to a single intake of either 50g of flavanol-rich dark chocolate (n=31) or 50g of optically identical flavanol-free placebo-chocolate (n=34). Two hours after chocolate intake, both groups underwent the 15-min Trier Social Stress Test. We measured DNA-binding-activity of the pro-inflammatory transcription factor NF-κB (NF-κB-BA) in peripheral blood mononuclear cells, as well as plasma and whole blood mRNA levels of the pro-inflammatory cytokines IL-1β and IL-6, and the anti-inflammatory cytokine IL-10, prior to chocolate intake as well as before and several times after stress. We also repeatedly measured the flavanol epicatechin and the stress hormones epinephrine and cortisol in plasma and saliva, respectively. Compared to the placebo-chocolate-group, the dark-chocolate-group revealed a marginal increase in IL-10 mRNA prior to stress (p=0.065), and a significantly blunted stress reactivity of NF-κB-BA, IL-1β mRNA, and IL-6 mRNA (p's⩽0.036) with higher epicatechin levels relating to lower pro-inflammatory stress reactivity (p's⩽0.033). Stress hormone changes to stress were controlled. None of the other measures showed a significant chocolate effect (p's⩾0.19). Our findings indicate that acute flavanol-rich dark chocolate exerts anti-inflammatory effects both by increasing mRNA expression of the anti-inflammatory cytokine IL-10 and by attenuating the intracellular pro-inflammatory stress response. This mechanism may add to beneficial effects of dark chocolate on cardiovascular health.

Effect of storage temperature on the decay of catechins and procyanidins in dark chocolate

“…In recent years, several studies have documented the beneficial effects of dark chocolate on human health. Dark chocolate has been reported to have a protective effect against chronic illnesses, especially cardiovascular diseases (Kuebler et al 2016;Montagnana et al 2017). It has also been proven that the polyphenols from dark chocolate have a protective effect on the function of erythrocytes (Radosinska et al 2017).…”

Effects of Interval Jump Rope Exercise Combined with Dark Chocolate Supplementation on Inflammatory Adipokine, Cytokine Concentrations, and Body Composition in Obese Adolescent Boys

“…The main source of pro-inflammatory cytokine secretion is adipose tissue. It has been reported that both JRE and dark chocolate supplementation reduces concentrations of pro-inflammatory cytokines [ 7 , 40 , 41 ]. For instance, Sung et al showed that 12 weeks of JRE decreased systemic inflammation by reducing hs-CRP concentrations in prehypertensive adolescent girls [ 7 ].…”

Polyphenols from Root, Tubercles and Grains Cropped in Brazil: Chemical and Nutritional Characterization and Their Effects on Human Health and Diseases

“…Many studies have demonstrated the beneficial effects of chocolate on the cardiovascular system [ 126 , 127 ], where polyphenol have been shown to attenuate intracellular pro-inflammatory reactivity [ 128 ]. In obese and overweight individuals, dark chocolate-polyphenols were equally effective in reducing fasting blood glucose levels, systolic and diastolic blood pressures, while a decrease in free urinary cortisone levels in both groups was also observed [ 129 ].…”