There’s good news for people with a sweet tooth, as a new study has revealed that eating dark chocolate could help you live longer.
Cocoa – the primary ingredient in dark chocolate – contains theobromine, a key compound naturally produced by plants.
New research has revealed that this compound reduces your biological age – a measure of how much damage people’s cells have accumulated over time.
While the experts are not exactly sure how theobromine has this anti-ageing effect, chomping down on your advent calendar this Christmas may not do the trick.
Theobromine – which gives unsweetened chocolate its bitter taste – is only in significant amounts in chocolate with high cocoa content.
Even dark chocolate can have a high fat and sugar content, which means it should be eaten in moderation as part of a balanced diet.
‘We’re not saying that people should eat more dark chocolate,’ said study author Jordana Bell, a professor of epigenomics at King’s College London.
‘But this research can help us understand how everyday foods may hold clues to healthier, longer lives.’
A chemical found in dark chocolate called theobromine could slow the rate of biological ageing, report researchers at King’s College London (file photo)
The study looked at health data of individuals from two cohorts – 509 from TwinsUK and 1,160 from Germany’s KORA.
These 1,669 individuals had an average age of 60 and were generally healthy, not selected for particular diseases.
To assess biological age, the team focused on chemical changes in DNA and the length of telomeres, the protective caps on the ends of chromosomes.
Like an aglet on a shoelace, telomeres stop the genetic material from unravelling and becoming damaged. Shorter telomeres are associated with ageing and age-related diseases.
According to the findings, those with higher levels of theobromine circulating in their blood had a biological age that was lower than their actual (‘chronical’) age.
After testing whether other metabolites in cocoa and coffee showed a similar link, they found the effect seemed to be specific to theobromine.
This important alkaloid, known as being poisonous to dogs, has been linked to health benefits in humans, such as a lower risk of heart disease.
It is already thought to lower blood pressure, promote fat metabolism, boost blood flow, enhance cognitive function and combat age-related cognitive decline.
Across two European cohorts, which included 509 individuals from TwinsUK and 1,160 from KORA, the research found that those who had higher levels of theobromine circulating in their blood had a biological age that was lower than their actual age
Theobromine is the primary alkaloid found in cocoa and therefore chocolate. Caffeine is also in cocoa, although in lower amounts than in coffee
The team report: ‘Theobromine, a commonly consumed dietary alkaloid derived from cocoa, has been linked to extended lifespan in model organisms and to health benefits in humans.
‘Here we report a significant association between circulating levels of theobromine with slower epigenetic ageing in two independent population-based cohorts.’
The team are not sure yet whether the effect is unique to theobromine alone, or whether theobromine may interact with other compounds in dark chocolate, such as polyphenols, which are known to have beneficial effects on human health.
Plant compounds in our diet such as this may affect how our bodies age by changing the way our genes are switched on or off.
Some of these compounds can interact with ‘cellular machinery’ that controls gene activity and helps shape health and longevity.
The findings, published today in Aging, follows follows many other papers exploring the benefits of eating cocoa, the primary ingredient in chocolate.
A 2023 study at Mass General Brigham Hospital in Boston found cocoa may reduce cognitive decline in people at high risk of dementia.
In 2021, scientists at Columbia University found consumption of cocoa was linked to improved performance in list-learning tasks due to flavanols, compounds abundant in cocoa as well as berries, apples, tea, and leafy veg.
And in 2019, Portuguese researchers said eating a few squares of dark chocolate every day lowers blood pressure in just one month.
However, there’s less evidence suggesting the health benefits of milk chocolate, which contains scant amounts of cocoa.
Commercially available chocolates on the market are increasingly packed with milk, sugar and fats at the expense of cocoa mass.
Some don’t contain enough cocoa to be permitted to be marketed as chocolate, which is why they instead have the label ‘chocolate flavoured’.
Generally, consumers are advised to enjoy chocolate as part of a balanced diet and active lifestyle, but opt for dark chocolate over milk chocolate to get the health benefits of theobromine and other compounds.
‘Exact proportions [of theobromine] vary across foods and also depend on food processing methods,’ Professor Bell told the Daily Mail.
‘Dark chocolate is high in cocoa solids, milk chocolate has lower levels and white chocolate has none.’



