People who eat chocolate regularly tend to be thinner, new research suggests.

一项新研究显示，定期吃巧克力的人身材能更苗条。

The findings come from a study of nearly 1,000 US people that looked at diet, calorie intake¹ and body mass index (BMI) - a measure of obesity².

It found those who ate chocolate a few times a week were, on average, slimmer than those who ate it occasionally.

Even though chocolate is loaded with calories, it contains ingredients（材料） that may favour weight loss rather than fat synthesis, scientists believe.

Despite boosting calorie intake, regular chocolate consumption was related to lower BMI in the study, which is published in Archives of Internal Medicine.

The link remained even when other factors, like how much exercise individuals did, were taken into account.

And it appears it is how often you eat chocolate that is important, rather than how much of it you eat. The study found no link with quantity consumed.

According to the researchers, there is only one chance in a hundred that their findings could be explained by chance alone.

Lead author Dr Beatrice Golomb, from the University of California at San Diego, said: "Our findings appear to add to a body of information suggesting that the composition of calories, not just the number of them, matters for determining their ultimate impact on weight."

This is not the first time scientists have suggested that chocolate may be healthy for us.

Other studies have claimed chocolate may be good for the heart.

Consumption of certain types of chocolate has been linked to some favourable³ changes in blood pressure, insulin（胰岛素） sensitivity and cholesterol⁴（胆固醇） level.

And chocolate, particularly dark chocolate, does contain antioxidants（抗氧化剂） which can help to mop up harmful free radicals⁵ - unstable⁶ chemicals that can damage our cells.

Dr Golomb and her team believe that antioxidant compounds, called catechins（儿茶素） , can improve lean muscle mass and reduce weight - at least studies in rodents⁷ would suggest this might be so.

Mice fed for 15 days with epicatechin (present in dark chocolate) had improved exercise performance and observable changes to their muscle composition.

They say clinical trials are now needed in humans to see if this is the case.

But before you reach for a chocolate bar, there are still lots of unanswered questions. And in the absence of conclusive⁸ evidence, experts advise caution.

While there's no harm in allowing yourself a treat like chocolate now and again, eating too much might be harmful because it often contains a lot of sugar and fat too.

And if you are looking to change your diet, you are likely to benefit most from eating more fresh fruits and vegetables.