Ultra-processed protein foods have become a staple in many diets, especially among fitness enthusiasts and wellness influencers. But are they as beneficial as they seem? A recent study has raised concerns, suggesting that ultra-processed protein sources may be detrimental to muscle health. However, experts argue that the study's findings are not as straightforward as they seem.
The Study's Limitations
The study in question, published in the journal Radiology, found that individuals with diets high in ultra-processed foods had more fat infiltrating their thigh muscles compared to those who consumed more whole foods. However, the study did not differentiate between ultra-processed protein sources and other types of ultra-processed foods. This means that participants may have been consuming protein bars, but their diets could have been high in fat and refined carbohydrates as well.
Additionally, the average age of participants was around 60, which may not be representative of the general population. Stuart Phillips, a protein researcher and professor of kinesiology at McMaster University, believes that the study's findings should not be generalized to all ultra-processed protein sources.
The Role of Protein Intake
According to Phillips, muscle-building is largely dependent on total protein intake and amino acid profile. He argues that if the protein dose, amino acid profile, and daily total are adequate, the processing level of the protein source is largely irrelevant to muscle protein synthesis and muscle-building outcomes. In other words, a whey isolate is not a Twinkie, even if they are both classified as ultra-processed by the NOVA system.
Essential amino acids, particularly leucine, play a key role in muscle protein synthesis. The body does not distinguish between leucine from a whey supplement and leucine from a steak. Therefore, when choosing a protein supplement or fortified food, it is important to prioritize options that contain leucine. If this information is not available, it is recommended to prioritize high-quality whole-food protein sources such as meat, dairy, soy foods, lentils, and salmon.
The Importance of Total Protein Intake
Total daily protein intake is also crucial. Phillips's research suggests that there is a ceiling beyond which additional protein offers little benefit. For most healthy individuals, this ceiling is around 1.6 grams of protein per kilogram of body weight per day. However, there are exceptions. Younger people doing resistance training may benefit from hitting this target, while adults over 65 may do well with between 1.2 and 1.6 grams per kilogram.
The Bottom Line
As a dietitian, Abby Langer recommends getting the majority of protein from whole foods. However, she acknowledges that life is not always ideal, and protein supplements can be a practical fallback in those situations. The key is to prioritize consistency in the quality and variety of the food you eat, including protein.
In conclusion, while the study raises valid questions about the impact of ultra-processed protein sources on muscle health, it is important to consider the limitations of the research and the overall protein intake and amino acid profile. By focusing on whole foods and prioritizing high-quality protein sources, individuals can achieve their fitness goals without sacrificing their health.
