Our previous post (see below or click here) discussed the impact exercise on long-term strength. In a nutshell, exercise has long term effects, even after the program has been halted. This week we will talk about new research that shows that dietary fats may also be important for muscle mass. Who’d have thought? Researchers are unsure how it works, but . . . dietary fat may influence protein turnover through its effects on inflammation and insulin. This may be important for long term health. Preserving muscle mass may be important for athletes and for maintaining a competitive edge. Loss of muscle mass occurs with age and is one of the leading contributors to frailty in the elderly. Preserving muscle mass may also allow people to enjoy active lives longer.
A study just published in the Journal of Nutrition looked at what types of fats were eaten by 2,689 women who are part of the UK study of twins. The women were between the ages of 18 and 79. Researchers also looked at ratios of the different types of fats (polyunsaturated /saturated fats), the percent of calories obtained from fat and the womens’ fat free mass. “Fat Free Mass” is used as an indicator for muscle mass. Its imperfect. Bone, of course, has mass. But people with higher fat free mass usually have more muscle mass.
Women who ate more polyunsaturated fats had the most fat free mass. Women who ate more transfats, saturated fats and monounsaturated fats had less fat free mass. The researchers also noted that the difference in fat free mass between women who ate mostly unsaturated fatty acids and those who ate mostly saturated fatty acids was about the same amount of fat free mass loss that occurs over the course of a decade. Interesting. These are, of course, correlations. More research will be needed to find out if it is certain that unsaturated fats can protect people from age-related loss of muscle mass.
Good sources of unsaturated fatty acids include:
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 PMID: 24401817