Being underweight brings higher risk of early death than being overweight

NEWDELHI: People who are underweight are at a higher risk of early death compared to those with a healthy weight, according to data from a large population-based study of 26,001 people of 20 years and above in Chennai. Those who are overweight or slightly obese carried no such risk.

Conventional wisdom indicates that people who are overweight are at higher risk of disease and death. “Our study indicated that instead of obsessing about body mass index (BMI), people should focus on cardiovascular fitness by being healthy and active,” said Dr Vishwanathan Mohan, director of the Madras Diabetes Research Foundation (MDRF), Chennai. The study, published in PLOS One, used Chennai Urban Rural Epidemiology Study (CURES) data and had a median follow-up of 10.3 years.

The study indicates that carrying a few extra kilos doesn’t hurt if people are active and fit. “A person who runs but is slightly overweight will have a lower risk of dying than a person who has a healthy weight but is inactive,” said Dr Mohan.

A major compounding factor is the overall health as low weight could be driven by malnourishment, tuberculosis, cancer or other illnesses. “Underweight people are almost always not healthy, so this finding didn’t surprise. What was unusual was that those who were overweight and slightly obese did not have a higher risk of death compared to healthy people, which could have been because the mean body mass index (BMI) was a low 24,” said Dr Ambrish Mithal, chairman, endocrinology, Medanta, Gurugram.

BMI is a height-weight ratio used to determine healthy weight. “To compare, the mean BMI in people with diabetes being treated in an urban, private-paying environment is between 28 and 30,” said Dr Mithal. The study found that people with diabetes have three times higher risk of dying than healthy people. Other contributors are physical inactivity, high LDL cholesterol and triglycerides, high blood pressure, smoking and alcohol use.