New research is casting doubt on the long-held belief that being heavy is not itself a health problem.
Excess weight or obesity boosts risk of death by anywhere from 22% to 91% –significantly more than previously believed, according to new Colorado University (CU) research.
The findings, published in the journal Population Studies, counter prevailing wisdom that excess weight boosts mortality risk only in extreme cases.
The study estimates that about one in six U.S. deaths are related to excess weight or obesity.
“Existing studies have likely underestimated the mortality consequences of living in a country where cheap, unhealthy food has grown increasingly accessible, and sedentary lifestyles have become the norm,” said author Ryan Masters, associate professor of sociology at CU Boulder.
“This study and others are beginning to expose the true toll of this public health crisis.”
Another study addresses the issue that people that were overweight according to their body mass index (BMI) were once considered less at risk of cardio vascular disease if they were heavily muscled.
The new study, published in the journal Preventative Medicine, shows that the negative impact of excess adiposity – fat tissue – on a person's cardio-metabolic health was not offset even by high levels of muscle mass.
The researchers looked at how the adiposity/muscle phenotypes related to lipid levels, including cholesterol and triglycerides, as well as blood sugar glucose and blood pressure. Results were also adjusted for age, sex, race and education.
"We wanted to see whether this proposed categorization was better than the traditional body-mass index (BMI) at predicting all these different cardiometabolic outcomes," says Sylvia Santosa, an associate professor in the Department of Health, Kinesiology and Applied Physiology at Concordia University in Montreal.
Surprisingly, they found BMI, though far from perfect, was in some cases a better predictor of cardiometabolic risks like diabetes and hypertension.
The high-adiposity/high-muscle group had unfavourable values for all cardiometabolic and adiposity measures. Nutrient intake was also lower.
This group was also 49 to 67 per cent less likely to meet physical activity recommendations, roughly 80 per cent more likely to have hypertension and 23 to 35 per cent more likely to exceed recommended saturated fat intake.
Overall, the high-adiposity/high- muscle phenotype was the least likely to meet physical activity and nutrient recommendations and was at the greatest risk of poor cardiometabolic health.