Researchers at the University of California, San Francisco, have found that following a diet rich in vitamins and minerals, especially one without too much added sugar, is associated with a younger biological age at the cellular level. The relevant paper was published in the online open version of the Journal of the American Medical Association on the 29th.

The study is one of the first to show a link between added sugar and epigenetic aging, and the first to explore this link in a racially diverse group of women.

The women in the study consumed between 2.7g and 316g of added sugar per day, with an average daily intake of 61.5g. A bar of milk chocolate contains about 25g of added sugar, while a 350ml can of cola contains about 39g of added sugar. The US Food and Drug Administration recommends that adults consume no more than 50g of added sugar per day.

The researchers looked at how three different healthy eating schedules affect the "epigenetic clock" (a biochemical test that can estimate health and lifespan). They found that the healthier people ate, the younger their cells looked. Among them, adhering to the Mediterranean diet was most strongly associated with a lower epigenetic age. The study also found that even if people ate a healthy diet, every gram of added sugar they consumed was associated with an increase in epigenetic age.

The study helps deepen our understanding of the relationship between sugar and health. The researchers said that epigenetic patterns appear to be reversible, and if we persist in reducing our intake of added sugar by 10 grams per day, it may be equivalent to turning back the epigenetic clock by 2.4 months.