Effects of Obesity Can Mirror Those of Aging
In a new paper, published in the journal Obesity Reviews, researchers from Concordia University in Montreal, Quebec, argue that obesity should be considered premature aging.
The study looked at how obesity predisposes people to developing several life-altering or life-threatening diseases typically seen in aging individuals: compromised genomes, weakened immune systems, decreased cognition, increased chances of developing type 2 diabetes, Alzheimer’s disease, cardiovascular disease, cancer and other illnesses.
The research team reviewed more than 200 papers that analyzed obesity’s effects, from the level of the cell to tissue to the entire body.
“We are trying to comprehensively make the argument that obesity parallels aging,” said Dr. Sylvia Santosa, associate professor of health, kinesiology and applied physiology in the Faculty of Arts and Science, and a Tier II Canada Research Chair in Clinical Nutrition.
“Indeed, the mechanisms by which the comorbidities of obesity and aging develop are very similar.”
The study was co-authored by Drs. Bjorn Tam, Horizon postdoctoral fellow, and José Morais, an associate professor in the Department of Medicine at McGill University.
The paper looks at ways obesity ages the body from several different perspectives. Previous research has already linked obesity to premature death. But the researchers note that at the lowest levels inside the human body, obesity is a factor that directly accelerates the mechanisms of aging.
For example, the team looked at the processes of cell death and the maintenance of healthy cells — apoptosis and autophagy, respectively — that are usually associated with aging.
Studies have shown that obesity-induced apoptosis has been seen in mice hearts, livers, kidneys, neurons, inner ears and retinas. Obesity also inhibits autophagy, which can lead to cancer, cardiovascular disease, type 2 diabetes and Alzheimer’s.
The researchers also write that obesity influences a number of gene alterations associated with aging. These include the shortening of telomeres, the protective caps found on the ends of chromosomes. Telomeres in patients with obesity can be more than 25 percent shorter than those seen in control patients, for example.
The authors further point out that obesity’s effects on cognitive decline, mobility, hypertension and stress are all similar to those of aging.
In addition, obesity plays a significant role in the body’s fight against age-related diseases. Obesity, the authors write, speeds up the aging 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 aging that features a progressive decline in muscle mass and strength.
Finally, the paper emphasizes 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.
Santosa says the inspiration for this study came to her when she saw how many obese kids were developing adult-onset conditions of diseases, such as hypertension, high cholesterol and type 2 diabetes. She also realized that the comorbidities of obesity were similar to that of aging.
“I ask people to list as many comorbidities of obesity as they can,” Santosa said. “Then I ask how many of those comorbidities are associated with aging. Most people will say, all of them. There is certainly something that is happening in obesity that is accelerating our aging process.”
Source: Concordia University
Pedersen, T. (2020). Effects of Obesity Can Mirror Those of Aging. Psych Central. Retrieved on August 3, 2020, from https://psychcentral.com/news/2020/03/01/effects-of-obesity-can-mirror-those-of-aging/154618.html