People who have extra body fat but also build and keep strong muscles may be less likely to develop serious health problems like heart, liver, or kidney disease, or to die early, according to a new study published in The Journal of Clinical Endocrinology & Metabolism.

Obesity happens when a person has too much body fat and is usually defined as having a body mass index (BMI) of 30 or higher. BMI is based on a person’s height and weight, but it doesn’t directly measure how much body fat someone has.

Too much body fat can harm the body and increase the risk of diseases such as diabetes, heart disease, and some types of cancer. Experts sometimes call this early stage of unhealthy fat buildup “preclinical obesity.”

In the study, researchers looked at data from over 93,000 people in the UK. They found that people with stronger grip strength, a simple test of muscle strength, were less likely to develop obesity-related organ problems or die early over about 13 years of follow-up.

Dr. Yun Shen from the Pennington Biomedical Research Center said, “Grip strength is easy to measure, and strength can be improved with weight training. This means it’s a simple, low-cost way to find people at risk early and help them stay healthier.”

The researchers also found the same protective link when using other muscle measurements, showing that muscle strength in general plays an important role in protecting health — even for people who have extra body fat.