A study of over 1 million Swedish men challenges the popular ‘fat but fit’ concept, demonstrating that being obese reduces the protective effect of fitness when it comes to early death.
For many, the New Year begins with new plans to be more fit and active. While we know that being fit can reduce our risk of unhealthy conditions such as cardiovascular disease and diabetes, a concept that has recently gained popularity is the notion of being ‘fat but fit’. However, the association between fitness and obesity in terms of mortality has not been well studied.
Researchers from Umeå University, Sweden assessed the aerobic fitness of the men during adolescence, reporting on associations between fitness and causes of death years later.
The researchers found that while men with highest measurements of aerobic fitness were at significantly reduced risk of death from all causes, they found that these beneficial effects were reduced in obese participants, even if these obese participants were aerobically fit. When the researchers assessed risk of death in normal weight individuals who were found to be aerobically unfit, they reported a 30% lower risk of death from all causes in these men, despite their lower fitness levels.
The researchers conclude that lower fitness levels during adolescence are associated with increases in the risk of death from all causes. Specifically, the risk of death was greater in obese men, despite higher fitness levels, when compared with normal weight participants who were found to be unfit. The study provides evidence that refutes the notion of ‘healthy obesity’.
Gabriel Högström, Anna Nordström, Peter Nordström. Aerobic fitness in late adolescence and the risk of early death: a prospective cohort study of 1.3 million Swedish men. International Journal of Epidemiology, 2015
Written by Deborah Tallarigo, PhD