Ultra-processed foods account for up to 60% of some people’s diets. These foods — which include ready-made snacks, soft drinks, and meals that contain additives, artificial colors, preservatives, and plenty of sugar, salt and fat — can cause heart disease, diabetes, obesity and some cancers.

And, according to a new study, they can make you age faster.

Researchers at the University of Navarra, Pamplona, in Spain, found telomeres are shortened after the consumption of ultra-processed foods. The work was conducted by Lucia Alonso-Pedrero and colleagues with the supervision of professors Maira Bes-Rastrollo and Amelia Marti.

The study is being shared at the European and International Conference on Obesity, being held virtually through Friday.

According to the study, telomeres, which are chromosomes that can be used as a marker for age, were twice as likely to be short in people who ate ultra-processed foods at least three times a day over an extended period of time.

“Telomeres are structures formed from a strand of DNA together with specialised proteins, and which are located at the ends of the chromosomes,” a press release about the findings states. “Each human cell has 23 pairs of chromosomes that contain our genetic code, and while the telomeres do not contain genetic information themselves, they are vital for preserving the stability and integrity of chromosomes and by extension, the DNA that every cell in our body relies on to function.”

As we get older, telomeres get shorter because each time a cell divides, part of the telomere is lost. Therefore, telomere length is considered to be a marker of biological age.

Researchers recruited 645 men and 241 women with an average age of 67.7 years. They were put in four groups of equal size (quartiles) from ‘low’ to ‘high’ based on their consumption of ultra-processed foods: fewer than two servings a day; two to 2.5 servings a day; more than 2.5 to three servings a day; and more than three servings a day.

The team found that as participants increased their consumption of ultra-processed foods, the likelihood of having shortened telomeres rose dramatically with each quartile above the lowest. The medium-low group increased 29%; medium-high 40%; and high 82%. The researchers also found a link between ultra-processed food and the risk of depression (especially in patients with low levels of physical activity), hypertension, overweight/obesity and all-cause mortality.

“In this cross-sectional study of elderly Spanish subjects we showed a robust strong association between ultra-processed food consumption and telomere length,” the authors concluded. “Further research in larger longitudinal studies with baseline and repeated measures of (telomere length) is needed to confirm these observations.”