Insulin resistance linked to low lean body mass
A recent study, published in the Journal of Diabetes and its Complications by Victor W. Zhong, Ph.D., postdoctoral fellow at the Northwestern University Feinburg School of Medicine Department of Preventative Medicine, found results demonstrating a link between increasing insulin resistance and lower lean body mass in aging adults. The results found that men with increasing insulin resistance had lower lean body mass compared with men who experienced stable or a low increase in insulin resistance between young adulthood and middle age.
This relationship was not seen in women, according to the researchers.
Lean Mass Loss and its consequences
Sarcopenia, the significant loss of lean mass and strength, is associated with numerous negative health consequences, including falls, hospitalization, and mortality in geriatric populations. There is currently no cure for age and disease-related lean mass loss, therefore, identifying factors that may prevent this process early in adulthood has an important role in improving quality of life in later life. This can also reduce any health-related costs and their subsequent economic burden.
Zhong and his colleagues utilized data from the CARDIA fitness study on 925 men and 1,193 women between the ages of 18 and 30 without diabetes in 1985-6. This study conducted physical examinations and laboratory tests at baseline, 2, 5, 7, 10, 15, and 20 years. A DXA assessment was done at year 20. Fasting serum blood glucose and insulin levels were obtained at baseline, 7, 10, 15, and 20 years. Additionally, a diet questionnaire and an exercise test were done at baseline and 7 and 20 years to assess cardiorespiratory fitness.
At year 20, participants were divided into quartiles, separated by sex, which were determined based on appendicular lean mass divided by BMI. For men, these quartiles were 0.89, 1.03, 1.13, and 1.26, whereas for women, it was 0.59, 0.69, 0.77, and 0.89. Participants were also grouped into one of three groups based on the amount of insulin resistance increase compared to baseline: low-stable (31.1% men, 46.8% women), medium (54.8% men, 40% women), and high (14.1% men, 13.2% women).
Researchers found that there was a link between the change in insulin resistance from aging and appendicular lean mass in men. They reported that the difference in body composition and fat distribution may be related to this difference in sex. When they adjusted their results for cardiorespiratory fitness, the researchers found that their previous finding only held true for adults without obesity. Despite these intriguing results, Zhong states he is unsure why this relationship is only seen in nonobese individuals. “For obese people, losing fat mass may be more important than specifically improving insulin sensitivity, although these two are not totally independent.” This research highlights an interesting finding; however, additional research must be done to better identify the relationship between these two linked factors and their implications on one’s health.