Eating too much sugar may accelerate cellular ageing
Anutrient-rich diet with few added sugars may slow the rate of biological ageing in women. Scientists found that middle-aged women who ate more foods packed with vitamins, minerals and antioxidants had ‘younger looking’ cells than those who consumed less nutrient-rich diets. They judged the youthfulness of cells by looking at chemical tags known as methyl groups on the surface of DNA molecules. These tweak the activity of specic genes without altering DNA code, a process known as epigenetic modication.
The pattern of these methyl groups changes as we age, which is believed to contribute to accelerated cellular ageing. While nutrient-rich diets were tied to slowed ageing, added sugars seemed to dampen the e ect.
In the study, women who consumed higher amounts of added sugars showed signs of hastened cellular ageing compared to others, even if they ate an otherwise healthy diet. ‘Added sugars’ refers to sugars added to food during production, such as those in sugarsweetened drinks and baked goods, as opposed to the naturally occurring sugars found in milk, fruits and vegetables. The new study is one of the rst to demonstrate a link between added sugar consumption and so-called epigenetic ageing. “We knew that high levels of added sugars are linked to worsened metabolic health and early disease, possibly more than any other dietary factor,” said Elissa Epel, a professor of psychiatry at the University of California, San Francisco. “Now we know that accelerated epigenetic ageing is underlying this relationship, and this is likely one of many ways that excessive sugar intake limits healthy longevity.”
Epel and her colleagues analysed food records catalogued by 342 women, aged 39 years old on average, over three nonconsecutive days. The team then scored each woman’s diet based on how closely it adhered to various established diets. These included the Mediterranean diet, which is rich in plants, whole grains and unsaturated fats and low in red meats, saturated fats and sugars. Another similar diet, called the Alternative Healthy Eating Index, specically emphasises foods and nutrients believed to reduce the risk of chronic disease. The researchers also devised a new measure of nutrient intake called the Epigenetic Nutrient Index. This includes nutrients linked to antioxidative and antiinammatory processes in the body, as well as to DNA maintenance and repair. For example, it includes vitamins A, C, B12 and E, along with folate and magnesium.
In addition to scoring people’s diets, the team assessed how much added sugar the women ate, which ranged between 2.7 and
316 grams of added sugar a day. The team calculated the participants’ epigenetic ages by looking at the DNA methylation of cells within saliva samples. The data revealed the links between diet and cellular ageing, but they only captured a snapshot. The ndings support the idea that eating nutritious foods low in added sugars may improve a person’s health span, meaning the period of their life in which they are healthy, not just surviving. However, more research is needed to assess how following these diets might a ect epigenetic ageing in the long run.