New Study Investigates the Role of Dietary Fiber Intake and Sarcopenia Risk

The aging process often brings about various health issues, including chronic low-grade inflammation, sarcopenia and functional decline. The loss of muscle mass between the ages of 40 and 80 is between 30% and 60% and is associated with disability, illness, and death.

According to a new study published last Monday in Nutrients, researchers investigated the role of dietary fiber intake and sarcopenia risk. Most of the research on sarcopenia tends to be driven around dietary protein intake, while dietary fiber intake has been shown to have a positive effect on cardiovascular and metabolic disorders. Fiber helps alter the gut microbiome and may have an effect on systemic inflammation which can impact sarcopenia, as inflammation has a negative effect on muscle mass and protein synthesis.

This new study included 981 individuals between 65 and 79 years of age. The research team looked at associations between fiber intake and muscle mass in older adults from the NU-AGE study. Assessments included short-physical performance battery test, handgrip strength, dual-energy X-ray absorptiometry, accelerometery, and a 7-day food diary. The average fiber intake for men was 23.5 g/day and 20.3 g/day for women. The data from the research team shows that individuals with higher fiber intake also had lower C-reactive protein levels.

As a result, women who had an above average dietary fiber intake had a significantly higher skeletal mass index compared to those below average. This same association was seen in men who did not have metabolic syndrome. This study included a large number of participants over diverse ethnic and cultural differences and used the gold standard assessment for skeletal muscle mass. Adequate dietary fiber is not only important for gut health but also for helping to reduce systemic inflammation and decreasing sarcopenia risk.

Additional nutrients to consider

Vitamin D is a key nutrient in musculoskeletal health. Systematic reviews and meta-analyses examined the benefits of vitamin D supplementation on physical performance, muscle mass, and strength in seniors. In all the randomized controlled trials the dosing ranged from 800 IU to 2000 IU per day and studies took place over a 10 week to 20-month period.

It is important to note that while vitamin D is important it is not the only key player. However, vitamin D supplementation is a cost-effective intervention that helps to reduce falls, provides health benefits, and can reduce health care costs. 

In addition, previous research has demonstrated that probiotics can significantly reduce established biomarkers of systemic inflammation in middle-age and older adults. There is evidence that age-related changes in the gut microbiome may be related to elevated inflammatory makers and other geriatric conditions such as sarcopenia, frailty, and cognitive decline secondary to reduced short chain fatty acid production. In addition, the immune system has a tendency to decline with age, which makes us more susceptible to infections as well as increasing our risk of other diseases. Probiotics have the potential to rebalance gut microbiota and modulate gut immune response, inhibiting the NF-κB pathway.

Fish oils also play a role in sarcopenia and functional decline. Their anabolic role is due to their anti-inflammatory benefits, improvements in insulin sensitivity, and stimulation of muscle protein synthesis. It takes approximately three months of supplementation to see improvements with only doses of 3 grams or more per day showing significant improvements in functional measures and muscle mass.

By Michael Jurgelewicz, DC, DACBN, DCBCN, CNS

Source: Montiel-Rojas D, Nilsson A, et al. Dietary Fibre May Mitigate Sarcopenia Risk: Findings from the NU-AGE Cohort of Older European Adults. Nutrients 2020, 12(4) 1075.