Obesity alone doesn’t raise risk of death

Obesity alone doesn’t make it more likely that somebody will die prematurely, a new study has found. In other words, if you are fat, but have no other metabolic risk factors, you don’t have a higher risk of death. Scientists at York University’s Faculty of Health in Canada published their study and findings in the journal Clinical Obesity (citation below).

Diabetes, hypertension, i.e., high blood pressure, and elevated cholesterol, for example, are metabolic risk factors.

Team leader, Jennifer Kuk, associate professor at the School of Kinesiology and Health Science, said:

This is in contrast with most of the literature, and we think this is because most studies have defined metabolic healthy obesity as having up to one metabolic risk factor.”

Kinesiology is the study of the mechanics of body movements. Kinesic communication, for example, means body language, i.e., non-verbal language using our bodies.

Obesity Alone
As this image shows, the man with obesity alone has the same risk of death as the slim woman below him. Hypertension, high cholesterol, and diabetes, however, increase the risk of death.

Obesity alone – no higher death risk

Diabetes, dyslipidemia, or hypertension alone increase the risk of premature death. Dyslipidemia refers to unhealthy levels of fat (lipids) in your blood.

This study, however, showed that obesity alone does not. In other words, an obese person who is otherwise healthy does not have a higher risk of death.

Therefore, a person with hypertension has a higher risk of death than somebody with obesity alone.

In this study, the researchers followed 54,089 adults of both sexes. They were from five cohort studies and included:

– Individuals with obesity alone.

– People with obesity and at least one other metabolic factor.

– Individuals with high glucose, lipids, or blood pressure alone.

– People with at least two metabolic factors.

– Individuals of normal weight.

Team examined death rates in each group

Prof. Kuk and colleagues looked at how many people in each group died. They then compared the figures with those of individuals with no metabolic risk factors and of normal weight.

Weight management guidelines today suggest that people with a BMI of 30+ should lose weight. The implication, therefore, is that obesity makes you unhealthy, even obesity alone, i.e., with no other metabolic risk factors.

In this study, the researchers found that 1-in-20 people with obesity had obesity alone.

Prof. Kuk said:

“We’re showing that individuals with metabolically healthy obesity are actually not at an elevated mortality rate. We found that a person of normal weight with no other metabolic risk factors is just as likely to die as the person with obesity and no other risk factors.”

“This means that hundreds of thousands of people in North America alone with metabolically healthy obesity will be told to lose weight when it’s questionable how much benefit they’ll actually receive.”

Put simply; if you have obesity alone, your risk of death is not greater than other people’s. Specifically, healthy people who are not obese.


‘Individuals with obesity but no other metabolic risk factors are not at significantly elevated all‐cause mortality risk in men and women’ J. L. Kuk M. Rotondi X. Sui S. N. Blair C. I. Ardern. Clinical Obesity. First published: 12 July 2018. https://doi.org/10.1111/cob.12263.

Video – Obesity alone doesn’t raise risk of death

In this York University video, Prof. Kuk talks about her latest study.