Researchers determined whether dietary supplementation with fish oil-derived omega-3 fatty acids improves muscle mass and function and thus helps prevent and treat sarcopenia.
As we age, our muscle mass and function decline progressively and can result in sarcopenia. Sarcopenia is the loss of muscle tissue that occurs as a part of the aging process. It can affect mobility and independence, particularly in the elderly. To counteract and slow this age-related decline, it has been recommended to increase protein intake and partake in regular exercise. However, many find it difficult to maintain the recommended exercise regimen and there is no evidence supporting the belief that increased protein intake can help stop muscle mass decline and function.
Difficulties with Muscle Loss
The decline in muscle mass has a negative effect on an individual’s ability to do simple everyday tasks such as walking, lifting items, and climbing stairs. Muscle mass typically declines in healthy people by a rate of approximately 0.5 to 1% per decade, however, if an individual suffers for a period of time from an acute illness or chronic disease this can significantly accelerate the process. Muscle strength also declines with muscle mass, typically at a rate of 1-2% per decade.A diagnosis of sarcopenia occurs when muscle mass and strength decrease below a certain threshold the patient.
Sarcopenia affects 10-30% of older people without major illness and living independently, and an even higher percentage of older people who are in care facilities and/or ill. It is associated with a loss of independence, fragility, and disability, and brings a two to three-fold increased risk of falling and mortality. With an aging population, the number of people affected by sarcopenia is expected to steadily increase over the next 25 years.To date, however, there are no effective therapeutics available for the prevention and treatment of sarcopenia.
Currently, the only lifestyle changes to help with sarcopenia are regular physical exercise and high-protein intake. However, several limitations are associated with these approaches such as a difficulty with adherence to regular resistance-type exercise to maintain adequate muscle mass and function. Also, there is inadequate data to support the effectiveness of a high-protein diet.
A Need for Alternative Prevention Methods
Therefore, there is a need for an alternative method to prevent or treat sarcopenia. A recent review by researchers in the United States published in Current Opinion in Clinical Nutrition and Metabolic Care investigated whether supplementation with fish oil-derived omega-3 fatty acids could potentially prevent and treat sarcopenia.
The results from recent epidemiological studies in vitro and in animals indicated dietary supplementation with fish oil-derived omega-3 fatty acids stimulated muscle protein synthesis, as well as improving muscle mass and function in inactive older adults. One study showed that healthy older women who regularly exercised and took 2-4g of fish oil supplements per day for three months had improved training-related muscle strength in comparison to women who did not include fish oil supplements to their diet. These results were supported by another study which showed that after six months of fish oil-derived omega-3 fatty acids supplementation (4 g per day), muscle mass and function was increased in healthy and physically active older adults.
On the other hand, a shorter study (12 weeks) and lower supplement dose (1.3g per day) showed no association with an improvement in muscle strength and physical activity of the participants. These results suggest, therefore, that a higher dose and extended period of supplementation is required for the fish oil-derived omega-3 fatty acids to have an impact on muscle mass and function. Furthermore, there is no evidence that omega-3 fatty acids have adverse effects on cardiometabolic health, unlike a high-protein diet, making it a safer alternative particularly for older adults susceptible to cardiometabolic diseases such as diabetes, heart disease, or stroke.
Given the difficulties of implementing and maintaining regular physical activity to help prevent and treat age-associated sarcopenia, the supplementation of fish oil-derived omega-3 fatty acid of at least 2 g per day appears to be an effective approach in the clinical care of older adults. Also, as the results suggest, fish oil supplementation with resistance exercise training could significantly improve muscle strength in older adults and therefore potentially reduce the risk of developing sarcopenia. Further studies are required to elucidate the exact mechanisms by which fish oil-derived omega-3 fatty acids mediate beneficial effects on muscle mass and function.
Written by Lacey Hizartzidis, PhD
Reference: Gray SR, Mittendorfer B. Fish oil-derived n-3 polyunsaturated fatty acids for the prevention and treatment of sarcopenia. Curr Opin Clin Nutr Metab Care. 2017 Dec 9. doi: 10.1097/MCO.0000000000000441.