Flavonoid consumption and cardiometabolic health: Potential benefits due to foods, supplements, or biomarkers?

Cocoa Flavanol Supplementation and Risk of Age-Related Macular Degeneration: An Ancillary Study of the COSMOS Randomized Clinical Trial

Importance

Abnormalities of choroidal blood flow in the eye are associated with occurrence of age-related macular degeneration (AMD). Cocoa flavanols show beneficial effects on vascular risk factors in small and short-term trials and may help reduce AMD risk.

Objective

To examine whether daily supplementation with cocoa extract, a source of flavanols, prevents the development or progression of AMD.

Design, Setting, and Participants

This was a prespecified ancillary study of the COSMOS (COcoa Supplement and Multivitamins Outcomes Study) trial, a double-blind, placebo-controlled, 2 × 2 factorial randomized clinical trial of a cocoa extract supplement and a multivitamin supplement in the prevention of cardiovascular disease and cancer among 21 442 US adults, including 12 666 women aged 65 years and older and 8776 men aged 60 years and older. The intervention phase was performed from June 2015 through December 2020; data analysis was completed in August 2024.

Intervention

Cocoa extract supplement (500 mg/day cocoa flavanols, including 80 mg (-)-epicatechin) or placebo.

Main Outcomes and Measures

The primary end point was a composite of incident cases of AMD plus cases of progression to advanced AMD (geographic atrophy, neovascular membrane, retinal pigment epithelium detachment, or disciform scar) among participants with AMD at baseline, based on self-report confirmed by medical record review.

Results

Mean (SD) participant age was 72.1 (6.6) years, and 12 666 participants (59.1%) were female. During a median (IQR) period of 3.6 (3.2-4.2) years of treatment and follow-up, 344 participants (1.6%) experienced a confirmed AMD event (316 incident AMD, 28 progression to advanced AMD). For the primary composite end point, there were 159 cases (1.5%) in the cocoa extract group and 185 cases (1.7%) in the placebo group (hazard ratio [HR], 0.87; 95% CI, 0.71-1.08; P = .21). Separate Cox models fitted because of evidence of nonproportional hazards (P = .048) indicated a 23% decreased risk in the cocoa extract group during the first 2 years of treatment (HR, 0.77; 95% CI, 0.59-1.01), with no added benefit for treatment beyond 2 years (HR, 1.06; 95% CI, 0.76-1.50). Similar time-dependent findings were observed for the secondary trial outcomes of incident visually significant AMD and advanced AMD.

Conclusions and Relevance

In this ancillary study of the COSMOS randomized clinical trial, cocoa extract supplementation for a median period of 3.6 years among older women and men had no effect overall on occurrence of AMD. However, a possible modest treatment effect early in the trial could not be ruled out, which warrants further investigation to clarify whether cocoa extract may help reduce AMD risk.

Trial Registration

ClinicalTrials.gov Identifier: NCT03205202.

Plasma Carotenoids and Polyphenols and Their Association with MetS: The Need for Nutritional Interventions

Metabolic syndrome (MetS) is characterized by increased pro-oxidative stress and a chronic inflammation state and their consequent alterations. Several studies have highlighted the protective effect of carotenoids and polyphenols in MetS patients. This study aimed to evaluate the plasma level of selected carotenoids and polyphenols and to determine their relationship with MetS severity, MetS components, and inflammatory markers in Polish adults with metabolic disorders. It was designed as a cross-sectional study. The final study group comprised 275 adults, including 158 women and 117 men. Data were collected on the frequency of consumption of selected food groups. Anthropometric measurements and blood samples were taken to determine the concentration of carotenoids, polyphenols, and indicators (parameters) of metabolic disorders. Plasma concentrations of selected carotenoids and polyphenols were low in adults with MetS. The highest concentrations of carotenoids and polyphenols in the blood were observed for lutein and phenolic acids (including gallic and p-coumaric acids). Nevertheless, a correlation was found between the individual bioactive compounds and MetS components. In terms of the lipid profile, our study showed that the plasma of the selected carotenoids and polyphenols positively correlated with HDL cholesterol (zeaxanthin; total carotenoids), LDL cholesterol (chlorogenic acid), triglycerides (lycopene), and the total cholesterol (kaempferol). We found that the level of CRP as a marker of inflammation negatively correlated with the concentration of zeaxanthin. In our study group, no relationship was found between the dietary antioxidant intensity and the variables studied, which may be attributed to the low frequency of consumption of the sources of bioactive compounds, such as carotenoids and polyphenols, but also to the metabolic disorders. Further research is needed to determine whether these associations are causally related to the metabolic syndrome or are a result of the pathologies of the syndrome or improper diet with a low intake of vegetables and fruit.

Micronutrient Supplementation to Reduce Cardiovascular Risk

BACKGROUND

Healthy dietary patterns are rich in micronutrients, but their influence on cardiovascular disease (CVD) risks has not been systematically quantified.

OBJECTIVES

The goal of this study was to provide a comprehensive and most up-to-date evidence-based map that systematically quantifies the impact of micronutrients on CVD outcomes.

METHODS

This study comprised a systematic review and meta-analysis of randomized controlled intervention trials of micronutrients on CVD risk factors and clinical events.

RESULTS

A total of 884 randomized controlled intervention trials evaluating 27 types of micronutrients among 883,627 participants (4,895,544 person-years) were identified. Supplementation with n-3 fatty acid, n-6 fatty acid, l-arginine, l-citrulline, folic acid, vitamin D, magnesium, zinc, α-lipoic acid, coenzyme Q10, melatonin, catechin, curcumin, flavanol, genistein, and quercetin showed moderate- to high-quality evidence for reducing CVD risk factors. Specifically, n-3 fatty acid supplementation decreased CVD mortality (relative risk [RR]: 0.93; 95% CI: 0.88-0.97), myocardial infarction (RR: 0.85; 95% CI: 0.78-0.92), and coronary heart disease events (RR: 0.86; 95% CI: 0.80-0.93). Folic acid supplementation decreased stroke risk (RR: 0.84; 95% CI: 0.72-0.97), and coenzyme Q10 supplementation decreased all-cause mortality events (RR: 0.68; 95% CI: 0.49-0.94). Vitamin C, vitamin D, vitamin E, and selenium showed no effect on CVD or type 2 diabetes risk. β-carotene supplementation increased all-cause mortality (RR: 1.10; 95% CI: 1.05-1.15), CVD mortality events (RR: 1.12; 95% CI: 1.06-1.18), and stroke risk (RR: 1.09; 95% CI: 1.01-1.17).

CONCLUSIONS

Supplementation of some but not all micronutrients may benefit cardiometabolic health. This study highlights the importance of micronutrient diversity and the balance of benefits and risks to promote and maintain cardiovascular health in diverse populations. (Antioxidant Supplementation in the Prevention and Treatment of Cardiovascular Diseases; CRD42022315165).

Effect of cocoa flavanol supplementation for the prevention of cardiovascular disease events: the COcoa Supplement and Multivitamin Outcomes Study (COSMOS) randomized clinical trial

BACKGROUND

Cocoa extract is a source of flavanols that favorably influence vascular risk factors in small and short-term trials, yet effects on clinical cardiovascular events are untested.

OBJECTIVES

We examined whether cocoa extract supplementation decreases total cardiovascular disease (CVD) among older adults.

METHODS

We conducted a randomized, double-blind, placebo-controlled, 2-by-2 factorial trial of cocoa extract supplementation and multivitamins for prevention of CVD and cancer among 21,442 US adults (12,666 women aged ≥65 y and 8776 men aged ≥60 y), free of major CVD and recently diagnosed cancer. The intervention phase was June 2015 through December 2020. This article reports on the cocoa extract intervention. Participants were randomly assigned to a cocoa extract supplement [500 mg flavanols/d, including 80 mg (-)-epicatechin] or placebo. The primary outcome was a composite of confirmed incident total cardiovascular events, including myocardial infarction (MI), stroke, coronary revascularization, cardiovascular death, carotid artery disease, peripheral artery surgery, and unstable angina.

RESULTS

During a median follow-up of 3.6 y, 410 participants taking cocoa extract and 456 taking placebo had confirmed total cardiovascular events (HR: 0.90; 95% CI: 0.78, 1.02; P = 0.11). For secondary endpoints, HRs were 0.73 (95% CI: 0.54, 0.98) for CVD death, 0.87 (95% CI: 0.66, 1.16) for MI, 0.91 (95% CI: 0.70, 1.17) for stroke, 0.95 (95% CI: 0.77, 1.17) for coronary revascularization, neutral for other individual cardiovascular endpoints, and 0.89 (95% CI: 0.77, 1.03) for all-cause mortality. Per-protocol analyses censoring follow-up at nonadherence supported a lower risk of total cardiovascular events (HR: 0.85; 95% CI: 0.72, 0.99). There were no safety concerns.

CONCLUSIONS

Cocoa extract supplementation did not significantly reduce total cardiovascular events among older adults but reduced CVD death by 27%. Potential reductions in total cardiovascular events were supported in per-protocol analyses. Additional research is warranted to clarify whether cocoa extract may reduce clinical cardiovascular events. This trial is registered at www.clinicaltrials.gov as NCT02422745.

ER stress in obesity pathogenesis and management

Given the unprecedented global pandemic of obesity, a better understanding of the etiology of adiposity will be necessary to ensure effective management of obesity and related complications. Among the various potential factors contributing to obesity, endoplasmic reticulum (ER) stress refers to a state of excessive protein unfolding or misfolding that is commonly found in metabolic diseases including diabetes mellitus, insulin resistance (IR), and non-alcoholic fatty liver disease, although its role in obesogenesis remains controversial. ER stress is thought to drive adiposity by dampening energy expenditure, making ER stress a likely therapeutic target for the management of obesity. We summarize the role of ER stress and the ER stress response in the onset and development of obesity, and discuss the underlying mechanisms involved with a view to identifying novel therapeutic strategies for obesity prevention and management.