Preservation of lean muscle mass matters for long term health and function. It is also important to those who want to gain muscle mass so they can look hot and/or awesome. it is also important for strength and for athletic performance. Whatever your interests, here is a report of a recent study on dietary fats and muscle mass.
Dietary Fat and Protein Turnover
Dietary fat may regulate protein turnover. The thought is that dietary fats influence both inflammation and insulin. This study was published in this month’s issue of the Journal of Nutrition. Study subjects were 2,689 women who are part of a study of twins in the UK. Data was collected on:
- Percent of Calories obtained from Fat
- Fatty acid profile
- Fat -free mass in kilograms (an indicator of muscle mass)
- Fat-free mass measured by X-Ray absorptiometry
Results of the Dietary Fat and Muscle Study
- Women whose diets were higher in polyunsaturated fatty acids had higher fat-free mass (more muscle).
- Women who got more of their calories from fat had less fat free mass (less muscle)
- Women who ate more saturated fat had less fat free mass (less muscle)
- Women who ate more unsaturated fatty acids had less fat free mass (less muscle)
- Women who are more transfats had less fat free mass (less muscle)
Women who were in the top 20% for energy intake from polyunsaturated fatty acids had about a pound more muscle mass than women who were at the bottom 20% for polyunsaturated fatty acid. This is about the same difference in muscle mass that would be seen in a 10 year aging period. You could look at this and say that a diet high in polyunsaturated fatty acids saves 10 years of muscle aging. And you might be right. Polyunsaturated fatty acids reduce inflammation and seem to protect against cardiovascular disease and cancer as well. We don’t know what drives age-related muscle loss. It might be related to the same factors that drive cell-aging in general.
The Simple Takeaway for Dietary Fat and Muscle Mass
This is the first study of its kind and more research is needed to figure out what is going on. However, this study supports the idea that a diet higher in polyunsaturated fatty acids is protective against loss of muscle mass. As many are sure to proclaim: correlation is not causation. That claim does not end arguments, although it is often used that way. It simply means that we need to know more. This is an interesting study that should lead to further investigation. Thanks to the team (Alisa Welch, Alex MacGregor, Anne-Marie Minihane, Jane Skinner, Anna Valdes, Tim Spector and Aedin Cassidy) for your hard work.
Welch AA, Macgregor AJ, Minihane AM, Skinner J, Valdes AA, Spector TD, & Cassidy A (2014). Dietary fat and Fatty Acid profile are associated with indices of skeletal muscle mass in women aged 18-79 years. The Journal of nutrition, 144 (3), 327-34 PMID: 24401817