Three or more servings of so-called “ultra-processed food” per day doubled the strands of DNA and proteins found at the end of chromosomes, called telomeres, to be lower than those that rarely do. Consuming such foods, scientists told European and international conference on obesity.
Small telomeres are a marker of biological aging at the cellular level, and studies suggest that diet is a factor for rapidly aging cells.
The correlation is strong, however, because the causal relationship between eating highly processed foods and fewer telomeres is speculative, the authors cautioned.
Each human cell has 23 pairs of chromosomes that contain our genetic code.
Telomeres do not contain genetic information, but are important for preserving the stability and integrity of chromosomes and, by extension, DNA that all cells of our body depend on to function.
As we get older, our telomeres naturally decrease because every time a cell divides, part of the telomere is lost.
Length reduction has long been recognized as a marker of biological age.
Scientists led by Professor Maria Bas-Rastrolo and Amelia Marti of the University of Navarra, Spain, sought to find a suspicious relationship between processed junk food and regular intake of shrinking telomeres.
No real food
Earlier studies had pointed to a possible link with sugar-sweetened beverages, processed meats and other foods rich in saturated fat and sugar, but the findings were inconclusive.
Ultra-processed foods are industrially manufactured foods made from certain blends of oils, fats, sugars, starch, and proteins, with little to no whole or natural foods.
They often include artificial flavorings, dyes, emulsifiers, preservatives, and other additives that increase shelf-life and profit margins.
However, these same qualities also mean that such foods are nutritionally worse than less processed alternatives, the researchers said.
Prior studies have shown a strong association between ultra-processed foods and some forms of hypertension, obesity, depression, type 2 diabetes, and cancer.
These conditions are often age related, as far as they are associated with oxidative stress and inflammation known to affect telomere length.
Marty and his colleagues looked at the health data of about 900 people 55 or older, who provided DNA samples in 2008 and then detailed data about their eating habits every two years.
The 645 men and 241 women were equally divided into four groups, depending on the consumption of ultra-processed foods.
The high intake group was more likely to have family history of heart disease, diabetes, and abnormal blood fat.
They also consumed less of the foods associated with the Mediterranean diet – fiber, olive oil, fruits, vegetables and nuts.
Compared to the group who eat the least amount of over-processed foods, the other three showed an increased likelihood – 29, 40, and 82 percent, respectively – of having small telomeres.
The findings were published in a peer-review earlier this year American Journal of Clinical Nutrition.