New Study: Greater Muscle Mass Is Linked to Greater Longevity
UCLA medical school researchers conducted a follow-up all-cause mortality survey of 3,659 men and women who participated in the National Health and Nutrition Examination Survey (NHANES) III. The men selected were aged 55 and over and the women were aged 65 and over, at time of the original survey conducted between 1988 and 1994. In the new study, the UCLA researchers found that the all-cause mortality was significantly lower in those older study participants with the highest muscle mass index than it was in those with the lowest muscle mass index. Specifically, the UCLA researchers found that total mortality was significantly lower in the fourth quartile of muscle mass index when compared to the first. UCLA researchers are using these results to further study the link between greater longevity and greater muscle mass.
In the new study the study participants’ body composition or muscle mass were measured using bio-electrical impedance, a process by which a safe and small electrical current is made to run through the body. The electrical current passes freely through the fluids contained in muscle tissue, but encounters difficulty or resistance when it passes through fat tissue because the muscles contain more water than fat. The UCLA researchers used this process to determine the muscle mass index of each study participant and they defined muscle mass index to be muscle mass divided by height squared.
According to Dr. Arun Karlamangla, one of the study co-authors, the greater your muscle mass, the lower is your risk of death and therefore older people should try to maximize and maintain muscle mass rather than worrying about their weight or Body Mass Index (BMI).
The UCLA study’s findings strongly suggest that overall body composition or muscle mass — and not the widely used BMI — is a better predictor of life span in older people.
It is important to remember that there is NO cause-and-effect established in the UCLA study – just because greater muscle mass and greater longevity occur together in older people, does not automatically mean that one caused the other, even if it seems to make sense. The UCLA study therefore does not prove that having greater muscle mass causes an older people to live longer but it does suggest that less muscle mass is a more important predictor of increased risk of natural death than body weight.
With aging, muscles begin to atrophy and the decrease in muscle also is linked to a decrease in activity and exercise that often occurs as people grow older. Strength training is essential because it can slow down muscle loss that comes with aging and it can also build the strength of your muscles and connective tissues, increase your bone density, cut your risk of injury, and help ease arthritis pain. Previous studies from the US Center for Disease Control & Prevention (CDC) have found that stamina building exercise can improve your balance, reduce your likelihood of falls, improve your blood-sugar control, and improve your sleep and mental health.
Dr. Lam’s Greater Longevity and Adrenal Health Perspective:
Adipose tissue, or fat, is an important component of your body, storing energy and providing warmth to maintain the body’s core temperature. Unfortunately, with the advent and increasing prevalence of convenience and processed foods in the modern diet, many people in developed countries now have far more adipose tissue than is necessary or even healthy.
For many people with a high fat to muscle ratio, the excess sugars and refined carbohydrates they consume are an important causal factor in the imbalances in the metabolic control and response systems of the body. These imbalances put them on the road to metabolic syndrome and diabetes. The prevalence of this occurring has led to the veritable epidemic of obesity, cardiovascular diseases and diabetes in developed countries.
The effects of this metabolic derangement cascade out and negatively affect other systems of the body, including inflammation, mental function and hormonal balance. In particular, the adrenal glands are put to work in an effort to offset the effects of stress from these imbalances; and since obesity and diabetes are usually chronic conditions, this stress can eventually drive the adrenals to overwork and fatigue. This connection from metabolic imbalances to other functionally critical systems of the body explains how improper eating and metabolic stress can have a strong effect in reducing longevity. Consuming a nutrient-dense diet and getting daily exercise leads to greater longevity and overall health.
Source: The UCLA study was published on Feb. 18, 2014 in the American Journal of Medicine and was titled “Muscle Mass Index as a Predictor of Longevity in Older-Adults” by Preethi Srikanthan and Arun S. Karlamangla