Key compound in dark chocolate may slow biological aging

New research has found that a chemical in dark chocolate has anti-aging properties. The team analyzed blood levels of the plant compound theobromine in relation to biological age markers.

Examining participant data from the TwinsUK and KORA studies, King’s College London, UK, researchers correlated higher theobromine levels to a younger biological age in two European cohorts of over 1,600 people.

Biological age is a benchmark of a person’s health and function, contrary to the number of years lived. These markers are based on methylation — patterns in human DNA that change over time.

The findings in Aging highlight the potential of dietary compounds to influence health and longevity, although further investigation is needed to clarify how theobromine interacts with other compounds in dark chocolate, such as polyphenols.

Senior author Jordana Bell, professor of Epigenomics at King’s College London, says: “Our study finds links between a key component of dark chocolate and staying younger for longer. While we’re not saying that people should eat more dark chocolate, this research can help us understand how everyday foods may hold clues to healthier, longer lives.”

Dark chocolate remains a treat

The King’s College London team also cautions against consuming excessive amounts of dark chocolate, as many commercial options usually contain sugar, fat, and other compounds that are not automatically beneficial for health.

They found the anti-aging effect was specific to theobromine after testing if other metabolites in cocoa and coffee had a similar effect. 

Theobromine is an alkaloid that has been found to lower the risk of heart disease in previous studies, note the researchers. However, not much is known about it otherwise.

Reacting to the study, Dr. Dimitrios Koutoukidis, associate professor in Diet, Obesity, and Behavioural Sciences and dietitian at the University of Oxford, UK, comments: “Although the study explores an interesting association, it does not tell us what happens when theobromine levels change due to eating more or less chocolate and how this changes our health.” 

Theobromine is an alkaloid that has been found to lower the risk of heart disease in previous studies, however, not much is known about it otherwise.“Chocolate, even dark one, is a treat, and not a healthful food. It might be that after taking into account the added sugar and fat of the chocolate, the health effects are cancelled out. So, if people like it, they should enjoy it infrequently and in small amounts.”

Diets impact on biological age

The researchers explain that plant compounds in diets affect how bodies age by “turning on or off” genes. These alkaloids interact with cellular components that regulate gene activity to promote health and longevity.

“This is a very exciting finding, and the next important questions are what is behind this association and how can we explore the interactions between dietary metabolites and our epigenome further? This approach could lead us to important discoveries toward aging and beyond in common and rare diseases,” says lead researcher Dr. Ramy Saad, King’s College London, who is also a researcher at University College London and a doctor in clinical genetics.

The scientists examined chemical changes in DNA to determine how quickly someone was aging. They also estimated the length of telomeres, as shorter telomeres are associated with aging and age-related diseases.

Dr. Ricardo Costeira, postdoctoral research associate at King’s College London, says: “This study identifies another molecular mechanism through which naturally occurring compounds in cocoa may support health. While more research is needed, the findings from this study highlight the value of population-level analyses in aging and genetics.”

Dr. David Vauzour, associate professor in Molecular Nutrition, University of East Anglia, UK, who is not involved in the study notes: “The current study is a well-designed observational metabolomics-epigenetics investigation. It provides novel evidence that higher theobromine is associated with slower epigenetic aging in blood.”

“However, association is not causation,” he cautions. “We cannot conclude that cocoa or chocolate consumption will slow aging, nor that theobromine is the causal agent.” 

“Given residual confounding factors (e.g., overall diet quality, lifestyle — exercise, sleep — socioeconomic status, etc.), metabolic variability, potential reverse causation, and the current limitations of epigenetic clocks, the findings should be seen as hypothesis-generating rather than definitive proof.”

He emphasizes that stronger evidence, including longitudinal studies, intervention trials, and mechanistic studies, is necessary before making any further claims.

Chocolate in health headlines

Dark chocolate’s impact on health is contested. Previously, researchers suggested that increasing dark chocolate consumption may help reduce the risk of developing type 2 diabetes. 

However, experts not part of the research pointed out that a cause-and-effect relationship cannot be established. They highlighted that the low occurrence of diabetes in people consuming dark chocolate may result in statistical uncertainties.

Another study found that dark chocolate enriched with extra virgin olive oil is associated with an improved cardiovascular risk profile. 

For boosting athletic performance, separate research found that eating dark chocolate daily may help.