Chocolate might not be the healthiest thing for your waistline – but research suggests it may protect against stroke.

A study following more than 37,000 Swedish men showed those eating the most chocolate were the least likely to have a stroke.

It follows on from other studies that have suggested eating chocolate can improve the health of the heart.

However, researchers and the Stroke Association warned the findings were not an excuse to overeat chocolate.

Everyone taking part in the study was asked about their eating habits and their health was monitored for a decade.

They were split into four groups based on the amount of chocolate, with the bottom group eating, on average, no chocolate each week and the top group having 63g (2.2oz) – slightly more than an average bar.

Comparing the top and bottom groups showed those eating the most chocolate were 17% less likely to have a stroke during the study, published in the journal Neurology.

Flavonoids

One of the researchers, Prof Susanna Larsson, from the Karolinska Institute in Sweden, said: “The beneficial effect of chocolate consumption on stroke may be related to the flavonoids in chocolate.

“Flavonoids appear to be protective against cardiovascular disease through antioxidant, anti-clotting and anti-inflammatory properties.

“It’s also possible that flavonoids in chocolate may decrease blood concentrations of bad cholesterol and reduce blood pressure.”

The study also noted that while dark chocolate had been linked to benefits for the heart in the past, milk chocolate was the preferred option in Sweden and in the study.

Dr Clare Walton, from the Stroke Association, said: “Past research has shown that eating dark chocolate might go some way to reducing your stroke risk if it is eaten as part of a healthy, balanced diet.

“This study suggests that eating a moderate amount of other types of chocolate could also be beneficial in men.

“However, a lot more research is needed and these results should not be used as an excuse for men to eat chocolate as an alternative to regular exercise or eating a healthy diet to reduce their risk of stroke.”

The authors of the study warned of the high sugar and fat content of chocolate.

“It should be consumed in moderation,” they said.