Can Cocoa Flavanols Protect Endothelial Function During Prolonged Sitting in Healthy Older Adults?

University of Birmingham

Status

Completed

Conditions

Healthy

Ageing

Treatments

Dietary Supplement: Low-flavanol cocoa powder

Dietary Supplement: High-flavanol cocoa powder

Study type

Interventional

Funder types

Other

Identifiers

NCT07265869

ERN_19-0851B

Details and patient eligibility

About

Sitting time is high in older adults and has been shown to temporarily impair endothelial function and blood pressure. Flavanols, plant-derived compounds, acutely enhance endothelial function and reduce Blood pressure in older adults. The aim of this study is to investigate whether acute ingestion of cocoa flavanols can improve peripheral endothelial function and blood pressure during prolonged sitting in healthy older adults.

In a randomised, double-blinded, cross-over, placebo-controlled human study, 20 healthy older adults will consume either a high-flavanol (695 mg) or low-flavanol (5.6 mg) cocoa beverage immediately before a 2-hour sitting bout. Flow-mediated dilation (FMD) of the superficial femoral (SFA; primary outcome) and brachial (BA) arteries, and blood pressure, were assessed before and after sitting. Microvasculature haemodynamics were assessed in the gastrocnemius before, during, and after sitting. It is hypothesized that the high flavanol cocoa will prevent declines in brachial and superficial femoral Flow-mediated dilatation post sitting.

Full description

Older individuals are estimated to spend more than 10 hours in their waking day in sedentary activities , which can include sitting bouts lasting up to 5.4 hours/day . Greater sedentary time was found to be associated with a significantly increased risk of cardiovascular diseases and all-cause mortality. Several experimental studies have shown that even just one isolated episode of prolonged sitting (from 1 to 6 hours) has detrimental effects on human endothelial function, as measured by flow-mediated dilation (FMD).

Flavonoid-rich foods are typically consumed in high amounts in cardioprotective diets, with evidence from both observational and Randomised Controlled Trials showing flavonoids to improve biomarkers of cardiovascular health. Flavanols, a sub-group of flavonoids present in unprocessed cocoa, have been extensively shown to act quickly within the vasculature, improving both brachial Flow-mediated dilatation and lower-limb common femoral artery (CFA) Flow-mediated dilatation within 2 hours of intake in older adults.

The aim of the current study is to examine whether acute consumption of cocoa flavanols prior to a 2-hour bout of uninterrupted sitting can be beneficial in improving endothelial function (as measured by Flow mediated dilatation) in the upper-limb Brachial Artery (BA) and lower-limb Superficial Femoral Artery (SFA) in older adults, as well as downstream, muscle microvascular function. We will further investigate whether cocoa flavanols can prevent sitting-induced increases in blood pressure in older adults. We hypothesise that cocoa flavanols would be effective at rescuing upper- and lower-limb Flow-mediated dilatation and improve blood pressure during uninterrupted sitting in older age

Enrollment

20 patients

Sex

All

Ages

65+ years old

Volunteers

Accepts Healthy Volunteers

Inclusion criteria

Males and females
aged 65 or more

Exclusion criteria

history or symptoms of cardiovascular, renal, pulmonary, metabolic, or neurologic disease, hypertension (blood pressure higher than 140/90 mm Hg, based on recent guidelines), diabetes mellitus, anaemia, asthma, immune conditions, or high cholesterol.
smoker
individuals who were on weight-reducing diets
individuals taking anticoagulants,
had recently undergone prolonged bed-rest periods
have been on antibiotics in the previous 3 months
have an infection at present (e.g. cold) or viral infection