Carrying even a little extra weight raises the risk of developing a severe form of COVID-19, especially in younger adults, according to a new study.

The findings published Thursday offer fresh insights into who is most at risk of complications, laying out the effects for certain age and ethnic groups and showing how weight gain matters.

The study comes as repeated lockdowns and pandemic stress lead to expanding waistlines in many developed countries and quashes the perception that only the obese face worse outcomes.

Those with a body mass index above 23, which is considered at the upper end of the healthy range, are already at higher risk, according to the U.K. researchers. They found that each one-point increase in BMI raises the chance of hospitalization by 5 percent and of intensive-care admission by 10 percent.

The impact was greatest in those under age 40, and the risks were amplified for Black people compared with other ethnic groups, the scientists found after studying the health records of almost 7 million people in England.

Being overweight had little effect on outcomes for people older than 80. The research was published in The Lancet Diabetes & Endocrinology journal.

— Bloomberg News