Maintaining Lean Body Mass As We Age
A healthy active lifestyle is key to the prevention of muscle mass loss, also known as Sarcopenia. Sarcopenia is the loss of muscle mass along with strength and mobility that occurs at a rate of 1-2% per year of healthy individuals over the age of 30 and at a much faster rate of 3-5% of whom are physically inactive. Muscle mass peaks at age 30 with a slow decline throughout the remainder of our life. Currently 3.6 million people suffer from this preventative condition. By the age of 80, most have lost up to 50% of their muscle mass compared to age 30.
Over the age of 60, we begin to lose muscle within 3 days of bed rest. The rate of muscle loss is three fold in 1/3 of the time. Testosterone is the primary hormone associated with Sarcopenia. Sedentary lifestyle exacerbates not only muscle loss but also coronary heart disease, degenerative joint disease, and osteoporosis which increase the risk for falls and injury. Sarcopenia is a predictor of survival independent of age, sex and functional status.
The elderly are at the highest risk due to pre-exisitng malnutrition. Up to 44% have nutritional deficiencies, specifically with protein. Most elderly are consuming 0.6 to 0.9 g/kg (grams per kilogram of body weight) of protein. The current RDA for 19+ years of age is 0.8 g/kg. However studies support an increase closer to 1.5 g/kg for this population.
Amino acids serve as metabolic signals needed for protein synthesis. They also alter inflammatory responses, increase energy production and satiety. For the prevention of Sarcopenia, it is suggested to spread the protein out throughout the day as it is directed into the muscle better. An example would be 30 grams with breakfast, lunch, dinner and a bedtime snack. The timing with protein intake and activity level is also important. It has been found that walking following dinner also helps direct protein into the muscle.
The new recommendations over the age of 65: 1.0-1.2 g/kg minimum for healthy people, 1.2-1.5 g/kg for acute or chronic illness, and up to 2.0 g/kg for severe illness, injury or malnutrition with healthy liver and kidney function.
Supplements to help maintain lean body mass are:
- Protein, such as whey, evenly distributed through out the day
- Vitamin D for muscle synthesis
- Fish oil as inflammation contributes to muscle loss
- Supporting gut health or microbiome, which is critical for metabolism and how the body handles proteins
