Fitness protects against diabetes
24 May 2016
A 20-year study has demonstrated that people with higher fitness levels are less likely to develop diabetes.
Doctors have long assumed that fitness is beneficial in preventing diabetes, but to date the evidence has been problematic, based on studies with mostly male participants over limited periods of time.
This study looked at fitness levels based on a treadmill test in 4,400 people without diabetes performed at various intervals over a 20 year period.
When the researchers correlated the results with incidence of a new diagnosis of diabetes, they found a lower risk with higher cardiorespiratory fitness levels, even when adjusting for BMI (body mass index).
Every 10% increase in fitness levels cut the risk of developing prediabetes or diabetes by 0.1%, the researchers from the University of Minnesota found.
Although this reduction is modest on an individual level, it is clinically significant at a population level, where small changes can translate into a large absolute reduction of disease, the authors say.
They say one mechanism behind the finding may be the beneficial effect of exercise on visceral fat - the fat that is stored in the abdomen around internal organs, which releases inflammatory chemicals that raise the risk of heart disease. Accumulation of visceral fat is associated with a higher risk of diabetes.
Another potential mechanism may be the anti-inflammatory effect of exercise, as type 2 diabetes is linked to low-grade systemic inflammation.
The findings show “exercise programs remain critically important for reducing the development of prediabetes and diabetes”, the researchers write in the journal Diebetologia.