Updated on March 4, 2022.
It may seem like baloney, but it turns out that the type of sandwich you eat each day could be making you age faster.
In a 2008 study published in American Journal of Clinical Nutrition, researchers found that people who ate the highest amount of processed meat—think salami, pressed ham, or pastrami—showed the greatest wear and tear in a key marker of cellular aging.
Telltale telomeres
To be specific, the people who ate the most processed meat had the shortest telomeres. Telomeres are protective coverings that cap off the ends of your DNA strands. The shorter they get, the older your body is on a cellular level—and the wider the door opens for chronic conditions like heart disease, diabetes, and certain cancers.
The researchers concluded that the telomeres of the processed-meat lovers showed about 3.4 extra years of aging compared with those who ate the least processed meat. A 2016 study of Native Americans published in Journal of Nutrition also linked eating processed meats to shorter telomeres.
The good news is that researchers have also found that eating more fruits and vegetables goes hand-in-hand with longer—and therefore younger and healthier—telomeres.
In a 2021 study published in Nutrients, researchers asked over 5,000 adults in the United States about their fruit and vegetable intake over the previous 24 hours, with the assumption that that would be a rough estimate of their usual habits. They also measured the volunteers’ telomeres. The more produce people had eaten, the longer their telomeres. Key exceptions: Telomere length didn’t correspond to potato or bean intake.
And a small but encouraging 2013 study of men with prostate cancer published in Lancet Oncology suggested that other lifestyle changes can actually lengthen telomeres. After three months of a healthy diet, 30 minutes of exercise and 60 minutes of yoga or meditation a day, and weekly support groups, participants’ telomeres got 10 percent longer. To make sure these findings hold true, larger, randomized controlled trials are needed to confirm the results.
A processing problem
What's so bad about processed meats? They tend to be packed with saturated fat, sodium, cholesterol, nitrates, and nitrites, some of which may be associated with telomere-shortening inflammation. Other studies have linked processed meat to higher risks of heart disease, diabetes, and even cancer.
So when it comes to fixing a sandwich that won’t shave years off your life, the healthiest approach is to reach for meats that are lean, skinless, and whole, such as sliced whole turkey or chicken breast. Better still for optimal health, load your bread (whole grain, of course) with all-veggie ingredients.
