Shedding excess weight does much more for the long-term heart health of young people than building muscle, new research suggests.
It’s not that gaining muscle while young proved to be a cardiovascular problem. It’s just that losing fat offered bigger heart benefits.
“We absolutely still encourage exercise,” Joshua Bell, a senior research associate in epidemiology at the University of Bristol in England says.
“There are many other health benefits, and strength is a prize in itself,” he adds. “We may just need to temper expectations for what gaining muscle can really do for avoiding heart disease. Fat gain is the real driver.”
The study followed more than 3,200 Brits born in the 1990s. It found those who had primarily lost fat during adolescence and young adulthood were much less likely than those who had gained muscle to develop risk factors such as high glucose, inflammation or “bad” cholesterol by age 25.
Participants had scans to assess levels of body fat and lean mass at ages 10, 13, 18 and 25. Handgrip strength tests were also assessed at 12 and 25.
At 25, participants underwent blood pressure and blood sample testing to assess levels of roughly 200 metabolic factors viewed as “a gateway for heart disease and other health problems,” Bell explains.
Such factors included insulin, C-reactive protein, cholesterol, triglycerides, glucose, creatinine and branched-chain amino acids.
The result: For lowering risk factors for heart disease, “changes in body fat seem to matter much more than changes in muscle,” Bell shares. By some measures — such as lowering levels of “bad” cholesterol — fat loss appeared to be