Cocoa boosts blood circulation to legs and helps keep over 60s on their feet, study suggests 

Drinking hot chocolate could help over 60s stay on their feet after a study suggests cocoa boosts blood circulation in the legs. 

Those who drank a mug of flavanol-rich cocoa three times a day for six months were able to walk significantly further in a walking test at the end of the study period.

Researchers think the cocoa may have improved blood flow to participants’ calves and improved muscle function allowing them to go the extra distance.

A fifth of people over 60 in the UK have some degree of peripheral artery disease or ‘PAD,’ which is a narrowing of the arteries that reduces blood flow to the legs. 

The symptoms often strike when walking and include pain, tightness, cramping and weakness, which is comparable to the discomfort suffered by advanced heart failure patients.

Commenting on the findings, study author Professor Mary McDermott, at Northwestern University in Chicago, US, said: ‘While we expected the improvements in walking, we were particularly pleased to see that cocoa treatment was also associated with increased capillary density, limb perfusion, mitochondrial activity, and an additional measure of overall skeletal muscle health.’

‘If our results are confirmed in a larger trial, these findings suggest that cocoa, a relatively inexpensive, safe and accessible product, could potentially produce significant improvements in calf muscle health, blood flow, and walking performance for PAD patients.’

Study participants were randomly assigned to drink either a mug of flavanol-rich cocoa or a placebo powder packet without cocoa three times daily over six months.

Walking performance was measured at the beginning of the study and at six months for the 44 peripheral artery disease patients, all of whom were aged over 60.

They completed the six-minute walking test twice, at two and a half hours and 24 hours after drinking the beverage, as well as a treadmill test.

The participants also had the blood flow to their legs measured using an MRI scan, and those who consented had a calf muscle biopsy to evaluate muscle health.

The cocoa drinkers were able to walk up to 42.6 metres further in the final six-minute walking test completed at the end of the six month study.

But patients who drank the placebo beverage suffered a 24.2 metre decline in their walking distance at the end of the six-month period.

The finding was consistent with other studies, in which PAD patients experience a deterioration in their walking distance over time, if they go untreated.

The researchers highlighted that regular chocolate would not be expected to have the same effect as the flavanol-rich cocoa, which is commonly available natural unsweetened cocoa powder.

The team also discovered other improvements to muscle health. Boosts were observed in both mitochondrial activity, which helps cells to convert the energy from food, and capillary density, a vital factor in delivering oxygen to tissues during exercise.

Commenting on the study, Dr Naomi Hamburg, Chair of the American Heart Association’s Peripheral Vascular Disease Council, said: ‘We know that exercise therapy helps people with PAD walk further, and this early study suggests that cocoa may turn out to be a new way to treat people with PAD.

She added: ‘We will need larger studies to confirm whether cocoa is an effective treatment for PAD, but maybe, someday, if the research supports it, we may be able to write a prescription for chocolate for our patients with PAD.’

The study was published today (Fri) in the American Heart Association’s journal Circulation Research.