Obesity should be classed as a form of premature ageing, due to it predisposing people to acquiring potentially life-altering diseases normally seen in older individuals.

That is the headline finding from a study called Obesity and ageing: Two sides of the same coin – by the Concordia University in Canada.

Published in the journal Obesity Review, the study reviewed more than 200 papers that looked at obesity’s effects on human health.

Using the data from the papers, researchers looked at the ways obesity ages the body from several different perspectives – from the immune system to shifts in tissue and body composition.

The study was led by Sylvia Santosa, associate professor of health, kinesiology and applied physiology in the Concordia University's Faculty of Arts and Science.

Santosa and her colleagues looked at the processes of cell death and the maintenance of healthy cells — apoptosis and autophagy, respectively — that are usually associated with ageing.

At the genetic level, the researchers found that obesity influences a number of alterations associated with ageing. These include the shortening of protective caps found on the ends of chromosomes, called telomeres.

Telomeres in patients with obesity can be more than 25 per cent shorter than those seen in control patients.

The study also suggests that obesity’s effects on cognitive decline, mobility, hypertension and stress are all similar to those of ageing.

“The mechanisms by which the comorbidities of obesity and ageing develop are very similar,” Santosa said.

Pulling out from the cellular level, the researchers say obesity plays a significant role in the body’s fight against age-related diseases.

The researchers concluded that obesity speeds up the ageing of the immune system by targeting different immune cells, and that later weight reduction will not always reverse the process. The effects of obesity on the immune system, in turn, affect susceptibility to diseases like influenza, which often affects patients with obesity at a higher rate than normal-weight individuals.

Obese people are also at higher risk of sarcopenia, a disease usually associated with ageing, which features a progressive decline in muscle mass and strength.

Finally, the paper spells out how individuals with obesity are more susceptible to diseases closely associated with later-life onset, such as type 2 diabetes, Alzheimer’s and various forms of cancer.

“I ask people to list as many comorbidities of obesity as they can, then ask how many of those comorbidities are associated with ageing, Santosa said.

"Most people will say, all of them. There is certainly something that is happening in obesity that is accelerating our ageing process."

In its conclusion, Santosa and her research team urges health authorities to rethink their approach to obesity.

“I’m hoping that these observations will focus our approach to understanding obesity a little more, and at the same time allow us to think of obesity in different ways," she added.

"We’re asking different types of questions than that which have traditionally been asked.”

• To read the full study, click here for the Obesity Reviews.