Researchers found that a higher intake of ultra-processed foods was associated with greater intramuscular fat in the thighs, independent of calorie intake, fat intake and physical activity, according to a study by multiple scientists.
The study examined the link between ultra-processed food consumption and fat infiltration in thigh muscles in people at risk for knee osteoarthritis. Intramuscular fat, similar to the marbling in a steak, could increase the risk for knee osteoarthritis, researchers concluded.
Ultra-processed foods are those that contain many additives, including fats, starches, added sugars and hydrogenated fats. They are often calorie-dense, flavorful and ready to eat. Examples include sugar-sweetened drinks, ultra-processed meats, refined grains, candy and commercial baked goods.
RELATED STORY | Following new USDA food pyramid would raise grocery bills by nearly one-third
The relationship between ultra-processed foods and health is complex. Not all are harmful, but many contain higher levels of saturated fat, added sugars and sodium, which can lead to excess calorie intake. Doctors have long warned that diets high in added sugars, sodium and saturated fats increase the risk for poor health outcomes. Because these foods are a major source of calories for many Americans, more people are at risk for negative health effects.
The association between ultra-processed foods and intramuscular fat had not been clearly established until recently.
“Over the past decades, in parallel to the rising prevalences of obesity and knee osteoarthritis, the use of natural ingredients in our diets has steadily diminished and been replaced by industrially processed, artificially flavored, colored and chemically altered food and beverages, which are classified as ultra-processed foods,” said the study’s lead author, Dr. Zehra Akkaya. “In addition to investigating the quality of our modern diet in relationship to thigh muscle composition, in this study, we used widely available, non-enhanced MRI, making our approach accessible and practical for routine clinical use and future studies.”
The study involved 615 individuals — 275 men and 340 women — with an average age of 60 and an average body mass index of 27. Researchers found that 41 percent of participants’ diets came from ultra-processed foods.
The findings underscore that diet quality — not just calorie restriction or exercise — plays a critical role in reducing the risk of osteoarthritis.
RELATED STORY | New US dietary guidelines urge more protein, fewer ultraprocessed foods
