Loss of muscle mass with aging in older adults can be a significant health concern because it may impair physical function and coordination, resulting in adverse conditions such as falls, broken bones, limited mobility, hospitalization, reduced quality of life, and even premature death. A major cause of the loss of muscle mass with advanced age is the inability of the aging muscle to adequately increase the rate of muscle protein synthesis in response to nutritional stimuli (e.g, amino acids and insulin) (1).

 

    Under the condition of high glucose, high insulin, and plenty of amino acids (precursors for protein synthesis) availability, young people could have twice as much muscle protein synthesis rate compared to that of old people (1). With the decreased capacity of muscle protein synthesis to regenerate muscles, older adults would experience gradual muscle loss over time. The less muscle mass and weakened muscles may not provide good support for the bones and movements, therefore more likely to fall and break their bones.

 

    The good news is that omega-3 fatty acids can enhance muscle protein synthesis in older adults (1). Sixteen healthy, older adults (10 men and 6 women, > 65 years of age) were randomly assigned to receive either omega-3 fatty acids or corn oil for 8 weeks. The rate of muscle protein synthesis and the phosphorylation of key elements of the anabolic signaling pathway were evaluated before and after supplementation during basal (such as after overnight fasting), postabsorptive conditions (such as after a meal), and during a hyperaminoacidemic-hyperinsulinemic clamp (such as a condition with plenty of nutrients promoting protein synthesis).

 

    Each study participant completed 2 stable-isotope-labeled tracer infusion studies to determine the effect of omega-3 fatty acid or corn oil (control group) supplementation on the rate of muscle protein synthesis and anabolic signaling in muscle during basal, postabsorptive conditions and combined amino acid and insulin infusions. The first study was performed before the intervention; the second study took place after 8 weeks of dietary supplementation with omega-3 fatty acids [4 g/d containing 1.86 g eicosapentaenoic acid (EPA) and 1.50 g docosahexaenoic acid (DHA) or an equal amount of corn oil].

 

    Corn oil supplementation did not affect the muscle protein synthesis rate and the extent of anabolic signaling element phosphorylation in muscle. Omega-3 fatty acid supplementation did not affect the basal rate of muscle protein synthesis but augmented the hyperaminoacidemia-hyperinsulinemia–induced increase in the rate of muscle protein synthesis (from 0.009 ± 0.005%/hour above basal values to 0.031 ± 0.003%/hour above basal values; p < 0.01), which was accompanied by greater increases in muscle mTORSer2448 (p = 0.08) and p70s6kThr389 (p < 0.01) phosphorylation, both markers for muscle protein synthesis.

 

    A recently published paper (2) reported on the effects of daily supplemental vitamin D, daily supplemental marine omega-3s fatty acids, and a simple home exercise program, alone or in combination, on the incidences of total and injurious falls among generally healthy older adults.

 

    This randomized controlled trial was done among 2157 community-dwelling adults aged 70 years and older, who had no major health events in the 5 years before enrolment, who were recruited from Switzerland, Germany, Austria, France, and Portugal between December 2012 and November 2014. Participants were randomly assigned to supplementation with 2000 international units/day of vitamin D3 and/or 1 g/day of marine omega-3s, and/or a simple home exercise program compared with placebo and/or control exercise over 3 years. The primary endpoint for the fall analysis was the incidence rate of total falls. Falls were recorded prospectively throughout the trial.

 

    Of 2157 randomized participants, 1900 (88%) completed the study. The mean age was 74.9 years, 61.7% were women, 40.7% had a serum 25-hydroxyvitamin D concentration < 20 ng/ml, and 83% were at least moderately physically active. In total, 3333 falls were recorded over a median follow-up of 2.99 years. Overall, vitamin D and the simple home exercise program had no benefit on total falls, whilst supplementation with omega-3s compared to no omega-3 supplementation reduced total falls by 10% (incidence rate ratio = 0.90; 95% CI, 0.81–1.00; p = 0.04).

 

    This study concluded that among generally healthy, active, and vitamin D–replete older adults, omega-3 supplementation may have a modest benefit on the incidence of total falls, whilst a daily high dose of vitamin D or a simple home exercise program had no benefit (2).

 

    The loss of muscle tissue as a natural part of the aging process is called sarcopenia. Physically inactive people can lose as much as 3% to 5% of their muscle mass each decade after age 30. Even if you are active, you would still have some muscle loss. Omega-3 fatty acid supplementation had been demonstrated to stimulate muscle protein synthesis in older adults and could be useful for the prevention and treatment of sarcopenia (1). It makes sense that the recent report showed that omega-3 supplementation has a modest 10% reduction in the incidence of total falls (2).

 

    Fish and fish oil (omega-3 fatty acids) consumption has been known for many health benefits, such as better cognition and better mood and sleep. In addition to those, the health benefits of fish and fish oil (omega-3 fatty acids) consumption can also include muscle protein synthesis and fall prevention. If you would like to enhance your muscle protein synthesis and preserve muscle mass, one thing you can do in addition to regular physical activity is to eat more fish.

 

References:

Smith, G. I., Atherton, P., Reeds, D. N., Mohammed, B. S., Rankin, D., Rennie, M. J., & Mittendorfer, B. (2010). Dietary omega-3 fatty acid supplementation increases the rate of muscle protein synthesis in older adults: a randomized controlled trial. The American Journal of Clinical Nutrition, 93(2), 402–412.

Bischoff-Ferrari, H. A., Freystätter, G., Vellas, B., et.al. (2022). Effects of vitamin D, omega-3 fatty acids, and a simple home strength exercise program on fall prevention: the DO-HEALTH randomized clinical trial. The American Journal of Clinical Nutrition, 115 (5), 1311–1321.