LONDON — Well-toned hips and a trim waist — not just the pounds you carry — appear to be one of the best protections against heart attacks, according to a study of thousands of people in different countries.
Researchers reported in Friday's issue of The Lancet medical journal that a hip-to-waist ratio is a better predictor of the risk of heart attack for a variety of ethnic groups than body-mass index, the current standard.
Based on weight and height, the body-mass index takes no notice of where fat is or how muscular a person is, said Dr. Arya Sharma, professor of medicine at McMaster University and co-author of the study. An athlete and a couch potato could have similar BMI scores, he noted.
"Irrespective of your BMI, your waist-hip ratio is important."
Previous research has shown that having a potbelly is a better predictor of heart trouble than weight, but most of those studies focused on Europeans or North Americans.
The Interheart study, directed by Dr. Salim Yusuf of McMaster University in Hamilton, Ontario, drew on data from 27,098 people in Europe, Asia, Africa and the Americas, including 12,461 who had suffered a heart attack.
In the new study, the risk of heart attack rose progressively as the ratio of waist size increased in proportion to hip circumference. The 20 percent of the survey who had the highest ratio were 2.5 times more at risk than the 20 percent with the lowest ratio, the study found.
That finding, researchers said, suggested a two-part strategy: trimming the abdomen, and possibly increasing hip size by increasing muscle mass or redistributing fat.
"This clearly will be a better way of identifying people at risk and helping avoid a heart attack," said Dr. Charmaine Griffiths of the British Heart Foundation, who was not involved in the research.