Published on September 23, 2026

A Better Predictor of Your Longevity Than Body Weight

Image of a woman using gym equipment

For many years, we have thought of body weight as an important way to predict how long someone may live. Many people use diets, medications and other treatments to lose weight in hopes of living a longer, healthier life.

But body weight does not tell the whole story. Your strength and muscle health may be better measures of how well your body is aging. Focusing only on the number on the scale can miss other important parts of your health.

It’s About More Than Your Weight

One problem with focusing only on body weight is that it does not tell us what that weight is made of.

Two people can weigh the same amount but have very different amounts of body fat and muscle. For example, someone who exercises regularly and has a lot of muscle may have a higher body mass index (BMI), even though they are physically fit.

That is why it is important to look at body composition, or how much of your body is made up of fat, muscle and other tissues.

Strength May Be a Better Measure

Research has found that muscle strength is linked to how long people live and their risk of certain health problems.

Grip strength is one example. Studies have found that grip strength can be a useful predictor of the risk of death from any cause and from heart disease. One study found that every 5-kilogram decrease in grip strength was linked to a 16% increase in the risk of death from any cause. Other studies have also found that lower muscle strength is linked to a higher risk of health problems and death.

Building and maintaining muscle strength may also help lower the risk of conditions such as heart disease, type 2 diabetes and other metabolic problems.

Why is Muscle So Important?

Muscle does much more than help us move. It also plays an important role in how our bodies use and store energy.

Skeletal muscle helps the body process blood sugar after we eat. Having healthy muscle can help the body respond better to insulin and may help lower the risk of type 2 diabetes and metabolic syndrome.

Muscle is also important when the body is under stress. During a serious illness, major surgery or severe infection, the body needs extra energy and protein to fight illness and repair damaged tissue. Muscle provides an important supply of protein that the body can use during these times.

As we age, we naturally lose some muscle mass and strength. This condition is called sarcopenia. A significant loss of muscle can increase the risk of serious health problems and death. When low muscle mass is combined with high levels of body fat, it is called sarcopenic obesity, which can further increase health risks.

Focus on Strength, Not Just the Scale

The number on the scale is only one part of your overall health. It is important to look at other measures, including your strength and ability to move.

For example, you can track your:

  • Grip strength
  • Leg strength
  • Ability to do push-ups
  • Ability to do chin-ups
  • Ability to step up and down safely
  • Overall ability to move and perform daily activities

This does not mean that body weight is unimportant. Instead, it means we should look at the whole picture when thinking about health and healthy aging.

Eating a balanced diet is important but so is giving your muscles regular exercise. Strength training can include going to the gym, taking a group fitness class or doing resistance exercises at home.

The key is to find activities that work for you and make them part of your regular routine. When it comes to maintaining muscle and strength as you age, consistency matters.

Dave Bearss, P.T., D.P.T., C.S.C.S., T.P.I., is a physical therapist who specializes in sports medicine and is a Certified Strength and Conditioning Specialist. He sees patients at the Campus Ridge Building, located on the campus of MyMichigan Medical Center Midland. To schedule an appointment, call the office at (989) 837-9100.

References

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Jochem, C., Leitzmann, M., Volaklis, K., Aune, D., & Strasser, B. (2019). Association Between Muscular Strength and Mortality in Clinical Populations: A Systematic Review and Meta-Analysis. Journal of the American Medical Directors Association, 20(10), 1213–1223. https://doi.org/10.1016/j.jamda.2019.05.015 Cited by: 115

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Momma, H., Kawakami, R., Honda, T., & Sawada, S. S. (2022). Muscle-strengthening activities are associated with lower risk and mortality in major non-communicable diseases: a systematic review and meta-analysis of cohort studies. British Journal of Sports Medicine, 56(13), 755–763. https://doi.org/10.1136/bjsports-2021-105061 Cited by: 408

Zhang, X., Xie, X., Dou, Q., Liu, C., Zhang, W., Yang, Y., Deng, R., & Cheng, A. S. K. (2019). Association of sarcopenic obesity with the risk of all-cause mortality among adults over a broad range of different settings: a updated meta-analysis. BMC Geriatrics, 19(1). https://doi.org/10.1186/s12877-019-1195-y Cited by: 228