Unhealthy diet, sedentary lifestyle may trigger ageing

Poor and unhealthy diet coupled with lack of exercise and a sedentary lifestyle may accelerate the ageing process in humans, warn US researchers.

A type of cells called senescent cells contribute to diseases and conditions associated with age.

The researchers found that exercise prevents premature senescent cell accumulation and protects against the damaging effects of an unhealthy diet, including deficiencies in physical, heart and metabolic function.

"We think that at both biological and clinical level, poor nutrition choices and inactive lifestyles do accelerate ageing," said senior author Nathan LeBrasseur from Mayo Clinic in the US.

In the study, researchers introduced mice to either a normal, healthy diet or a diet that they termed a "fast food diet" -- one that was high in saturated fat and cholesterol along with a sugar-sweetened beverage.

Mice on the fast food diet showed harmful changes in health parameters, including body weight and composition, increasing their fat mass by nearly 300 percent over the course of about four months.

Half the mice, including mice on both the healthy and unhealthy diets, were given exercise wheels.

The findings showed mice that had been exposed to the fast food diet but exercised showed suppression in body weight gain and fat mass accumulation and were protected against the accumulation of senescent cells.

"It doesn't mean that we need to be marathon runners but we need to find ways to increase our habitual activity levels to stay healthy and prevent processes that drive ageing and ageing-related diseases," LeBrasseur noted.