Ultra-Processed Foods Harm Muscle Health, Study Finds

A diet rich in ultra-processed foods has been linked to increased fat deposits within thigh muscles, regardless of calorie intake or physical activity levels, according to a study presented at the Radiological Society of North America's annual meeting. These fat deposits, known as intramuscular fat, can elevate the risk of knee osteoarthritis, a growing global health concern.

"This is the first study using MRI imaging to explore the relationship between diet quality and muscle composition,"

– said Dr. Zehra Akkaya, lead author and researcher at the University of California, San Francisco. The study highlights how poor dietary choices can negatively affect musculoskeletal health, even in individuals who are physically active or have a healthy weight.

Key Findings

Researchers analyzed data from 666 participants (average age 60, average BMI 27) involved in the Osteoarthritis Initiative, a large-scale study aimed at understanding and managing knee osteoarthritis. Key observations include:

• 40% of participants’ diets consisted of ultra-processed foods, such as packaged snacks, sugary drinks, and frozen meals.
• Higher consumption of these foods was strongly linked to increased intramuscular fat in the thighs, regardless of caloric intake, BMI, or physical activity levels.
• Fatty degeneration in muscles, visible through MRI imaging, is a precursor to knee osteoarthritis, where fat replaces muscle fibers, reducing strength and functionality.

Why Ultra-Processed Foods Are Harmful

Ultra-processed foods often contain artificial flavors, colors, and preservatives, making them convenient but detrimental to health. These foods, including breakfast cereals, packaged bread, and ready-to-eat meals, are designed to be appealing and addictive, combining sugar, fat, salt, and refined carbohydrates that stimulate the brain's reward system.

"Even without overeating, these foods contribute to unhealthy fat deposits," Dr. Akkaya noted, adding that lifestyle modifications, including a balanced diet and regular exercise, are crucial for preventing conditions like osteoarthritis.

Implications for Health

Osteoarthritis, heavily linked to obesity and poor diet, is a leading cause of non-cancer healthcare costs worldwide. Understanding how ultra-processed foods impact muscle composition offers a new perspective on disease prevention and management.

"Targeting modifiable lifestyle factors, such as reducing ultra-processed food intake, could play a critical role in improving muscle quality and preventing musculoskeletal disorders," said Dr. Akkaya.

This research emphasizes the importance of adopting a diet rich in natural, minimally processed ingredients to maintain muscle health and overall well-being.