Obesity increases the risk of premature death even in people without high blood pressure, high cholesterol and diabetes, according to a review of studies challenging the idea of "healthy obesity."
Researchers in Toronto collected information from eight studies on more than 60,000 people to determine whether people who are obese remain healthy in the long term.
Their answer is no.
"Our results do not support this concept of 'benign obesity' and demonstrate there is no 'healthy' pattern of obesity," Dr. Caroline Kramer at Mount Sinai and her co-authors concluded.
Earlier this year, the myth of healthy obesity was supported by the findings of a study in the Journal of the American Medical Association (JAMA) that concluded being overweight or obese (body mass index of 25 to 34.9 kilograms per metre squared) were associated with lower risk of death from all causes.
But Kramer's team found obese individuals showed an increased risk for deaths and cardiovascular events such as heart attacks, strokes and congestive heart failure when followed for 10 years or more.
The length of followup is key to the evaluation, the researchers said.
The Mount Sinai analysis also showed that obesity seems to increase the risk of premature death and cardiovascular events over the long term even in the absence of metabolic syndrome — the cluster of high blood pressure, high cholesterol and diabetes. The same was true for people who are overweight and metabolically unhealthy.
"We found that people with obesity, metabolically healthy obesity, they had 24 per cent [greater risk of] more events — cardiovascular events, heart attack, stroke and death — compared to people with normal weight, metabolically healthy," said Kramer.
"We are not telling people that they have to be skinny, but these results show that if you're overweight, if you are already obese, you should make changes."
Better well-being measurement needed, editorial says
The findings are consistent with the notion that obesity is a disease, doctors James Hill and Holly Wyatt of the University of Colorado said in a journal editorial published with the study.
Hill and Wyatt addressed what they called misconceptions about obesity, such as that weight loss and reducing metabolic and heart risks are the highest priority goals in treating obesity.
"Is a person who has lost enough weight to achieve normal metabolic measures but who has sleep problems, orthopedic issues, or difficulty managing stress really 'healthy?' Perhaps we need a more comprehensive measurement of well-being to measure success," the editorial writers suggested.
In public health terms, the priority should be preventing people who are overweight from becoming obese, they said.
Kramer's team did not account for smoking and physical activity in their review.
Suzanne Gracan is 5-6, weighs 220 pounds and does 30-kilometre bike rides regularly.
"I'd be interested in knowing who their subjects were," Gracan said of the findings.
"To generalize and to say that larger people are unhealthy is a stereotype," added Gracan, who created FitZonePlus in Toronto for plus-sized clients seeking yoga, Zumba and personal training.
Another limitation of the research is that it didn't consider elderly populations.
In 2011, about 18 per cent of Canadian adults were obese based on self-reported heights and weights, according to Statistics Canada.
The research was funded by the Leadership Sinai Centre for Diabetes.