Ultra-Processed Foods and Their Impact on Muscle and Joint Health

A recent analysis of multiple studies suggests a growing link between ultra-processed food consumption and musculoskeletal health risks, including knee osteoarthritis and diminished muscle integrity, prompting renewed calls for clearer public guidance on identifying and limiting these products.

Research published in the European Medical Journal (EMJ) found that individuals with higher intake of ultra-processed foods faced a significantly elevated risk of developing knee osteoarthritis, even after adjusting for body mass index and physical activity levels. The study, which analyzed dietary patterns and joint health in over 4,000 adults across Europe, indicated that additives, refined sugars, and unhealthy fats commonly found in packaged snacks, ready meals, and processed meats may contribute to systemic inflammation that accelerates cartilage breakdown in weight-bearing joints.

These findings align with parallel research from NBC News and Medical News Today, which reported that ultra-processed diets may negatively affect muscle health by promoting fat infiltration within muscle tissue — a condition sometimes described as turning muscle into “well-marbled steaks.” Imaging studies cited in the reports showed that participants consuming more than 40% of their daily calories from ultra-processed sources exhibited higher levels of intramuscular fat, particularly in the thighs, which is associated with reduced strength, slower metabolism, and increased frailty risk over time.

Despite growing awareness, many consumers struggle to identify what qualifies as ultra-processed food. A survey conducted by researchers at the University of Glasgow and reported by News-Medical found that while over 70% of UK adults expressed a desire to reduce their intake of such foods, fewer than 30% could correctly classify common items like flavored yogurts, breakfast cereals, or plant-based meat alternatives as ultra-processed under the NOVA classification system, which categorizes foods by the extent and purpose of industrial processing.

The NOVA system, developed by researchers at the University of São Paulo, defines ultra-processed foods as formulations made mostly or entirely from substances derived from foods and additives, with little if any intact whole food. Examples include sugary drinks, packaged breads, confectionery, savory snacks, reconstituted meat products, and pre-prepared frozen dishes. These items are typically high in added sugars, sodium, and unhealthy fats, and low in fiber, protein, and micronutrients.

Public health experts warn that the widespread availability and aggressive marketing of ultra-processed products make them difficult to avoid, especially in lower-income communities where fresh, whole foods may be less accessible or more expensive. Dr. Emily Roberts, a nutritional epidemiologist at the London School of Hygiene & Tropical Medicine, emphasized that while individual choices matter, structural solutions are needed. “We need clearer front-of-pack labeling, restrictions on marketing to children, and incentives for reformulation,” she said in a recent interview with the BBC. “Expecting consumers to decode complex ingredient lists isn’t a sustainable public health strategy.”

Current dietary guidelines in countries like the UK and the U.S. Do not yet formally address ultra-processing, though some agencies are beginning to acknowledge its potential health impacts. The Scientific Advisory Committee on Nutrition (SACN) in the UK is reviewing evidence on ultra-processed foods as part of its ongoing assessment of carbohydrate intake, with a report expected later in 2026. In the United States, the Dietary Guidelines Advisory Committee has called for more research but has not yet included processing level in its recommendations.

For individuals seeking to reduce risk, experts suggest focusing on whole or minimally processed foods — such as fresh fruits and vegetables, legumes, whole grains, eggs, and unprocessed meats — while limiting intake of items with long ingredient lists containing unfamiliar additives, emulsifiers, or artificial flavors. Cooking meals from scratch remains one of the most effective ways to avoid hidden sources of ultra-processing.

While the evidence linking ultra-processed foods to joint and muscle deterioration is still largely observational, researchers agree that the biological plausibility is strong. Chronic inflammation, insulin resistance, and disrupted gut microbiota — all associated with ultra-processed diets — are known pathways that can negatively affect connective tissue and muscle function over time.

As science continues to unpack how food processing influences long-term musculoskeletal health, the consensus among nutrition scientists is clear: reducing reliance on ultra-processed products represents a meaningful, though challenging, step toward better joint and muscle resilience, particularly as populations age.