Does eating chocolate help you live longer?

People who eat 12g of chocolate a day – roughly the equivalent of two pieces of a bar of chocolate - have a 12 per cent lower risk of dying, compared to those who don’t eat chocolate at all, according to new research published by the US National Cancer Institute.

They were also 16 per cent less likely to die from heart disease and 12 per cent less likely to die from cancer. However, they had the same risk of dying from stroke.

Using questionnaire results from a lifestyle study in Finland, researchers worked out how much chocolate more than 27,000 men ate daily. The men were recruited between 1985 to 1988, smoked five or more cigarettes per day, were aged between 50 to 69 and followed for up to 30 years, until 2015. During the follow-up period, the researchers recorded how many died and from what causes.

They also analysed data from 19 other previously studies, which included over 900,000 people. This showed further evidence that there was a link between eating chocolate and a lower risk of both having cardiovascular disease and dying from cardiovascular disease. However, there didn’t appear to be any more risk-lowering benefit to eating more than 5g (the equivalent to slightly less than one piece of chocolate) a day.

The researchers said that their findings may help to address some health concerns about eating a low-to-moderate level of chocolate but that more research was needed to find out what is the best amount of chocolate to eat.

How good was the research?

Strengths of this study include that the researchers included a large number of people in the study, and backed up their findings by comparing them with analysis of other past studies.

They also took into account and adjusted for other factors that could affect the risk of dying such as age, weight, how much they smoked, cholesterol and blood pressure levels, and any past history of cardiovascular disease.

Weaknesses in the study, meanwhile, include that it relied on questionnaire results – participants could misremember or understate how much chocolate they’ve eaten. However, in the Finnish study, booklets were included to help measure portion sizes.

The main study also focused on men, aged 50-69, who were smokers. However, the other studies considered by the researchers did include women. The people studied ate relatively low to moderate amounts of chocolate, so these findings shouldn’t be generalised to apply to eating higher amounts of chocolate.

Not all chocolate is made equal and it can vary widely in its nutritional content, depending on brand, ingredients, type of chocolate, and whether it includes dairy or plant-based ‘milk’.

While the study did mention brand names, portion sizes and package amounts, these may have changed over time since the study began. It may also be difficult to relate the findings, based on brands available in Finland, to chocolate from other countries.

As the researchers themselves say, these findings are observational and cannot prove that eating chocolate in itself directly lowers your risk of dying.

The BHF verdict

So, is chocolate good for you? Sindy Jodar, Senior Cardiac Nurse at the British Heart Foundation, said: “Although this study suggests chocolate can help keep your heart healthy, it did not have a conclusive enough result for us to recommend eating chocolate to improve your risk of cardiovascular disease.

“We already know that there may be beneficial compounds found in cocoa, but the chocolate products that we most commonly buy in the UK usually contain very little cocoa. All chocolate is high in calories because of its fat and sugar content and eating too much of it can lead to weight gain, which isn’t good for our heart and circulatory health.

“We all love chocolate and, although it’s fine to treat yourself every now and again, no single food or nutrient is more important than an overall balanced healthy diet. Plus, the antioxidants in cocoa that are thought to be behind the benefits can also be found in other foods that don’t come with added saturated fat and sugar, such as tea, berries and nuts.”

Overall, the authors of the study also state that further research is required into how much risk is reduced, the level of chocolate that is beneficial and that more work needs to be done in different populations.

• Find more expert advice on chocolate and how to keep a healthy, balanced diet in our nutrition section

How good was the media coverage?

The story was covered by both The Sun and regional newspapers such as Birmingham Live. Both publications only gave very brief overviews of the study and its content. Both newspapers also chose to focus on Cadbury Dairy Milk as an example of chocolate, despite the brand being consumed mainly in the UK, while the study itself looked at men in Finland.

The Sun incorrectly stated that, “Regular consumers’ risk of fatal heart disease or cancer falls by up to 16 per cent,” when cancer risk is listed in the study as 12 per cent less, rather than 16 per cent.

The Sun also said, “Fans who munch the equivalent of two Dairy Milk bars a week were four times less likely to suffer diabetes than those who eat none,” when this is not mentioned in the study.

Neither newspaper highlighted that the study did not find any additional benefits to eating more than 5g (around one piece) of chocolate per day.

They also focused on the idea of being less likely to die “young”, without providing a definition of what they consider to be “young”. In fact, the study looked at men who were 50 to 69 at the start of the study and followed them over a period of up to 30 years.

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