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The #1 Cause of Obesity According to Physicians

It’s much more complicated than you might realize.

Obesity is officially a public health crisis in the US, with over 41% of adults and almost 20% of children classed as obese. "This country is facing what I would call an epidemic, but we still have a health care system that's not prepared to handle this population," says Dr. Robert Kushner, an obesity medicine specialist at Northwestern University's Feinberg School of Medicine. Here are the main causes of obesity, according to experts. Read on—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.



Man and woman holding their bellies while sitting on the bed suffering from extra weight.

University of Virginia scientists recently identified 14 genes associated with obesity and three genes associated with preventing weight gain, paving the way for new obesity therapies and treatments. "We know of hundreds of gene variants that are more likely to show up in individuals suffering obesity and other diseases. But 'more likely to show up' does not mean causing the disease," says Eyleen O'Rourke of UVA's College of Arts & Sciences, the School of Medicine's Department of Cell Biology and the Robert M. Berne Cardiovascular Research Center. "…Our first round of experiments uncovered more than a dozen genes that cause and three genes that prevent obesity. We anticipate that our approach and the new genes we uncovered will accelerate the development of treatments to reduce the burden of obesity."


Sleep Problems

Sleep disorder, insomnia. Young blonde woman lying on the bed awake

Lack of sleep is strongly linked to obesity, experts warn. "The possibility that sleep – the most sedentary activity of all – contributes to the obesity epidemic is gaining recognition in the scientific community," says Jean-Philippe Chaput, PhD. "On a hormonal level, lack of sleep may disrupt a number of hormones that affect our drive to eat. Less time spent sleeping also means more time and opportunities for eating. Lack of sleep has been shown to increase snacking, the number of meals eaten per day, and the preference for energy-dense foods."




Chronic, unchecked stress is directly related to weight gain. "When people are facing a stressful situation, a chain reaction is set off in the body that results in the release of cortisol, leading to higher levels of this hormone in the body," says Sarah Jackson, PhD. "Cortisol is involved in a broad range of biological processes, including metabolism, body composition and the accumulation of body fat. When we're stressed out we may also find it more difficult to find the motivation to go for a run or resist unhealthy foods."


Obesity and COVID-19

Blood test samples for presence of coronavirus

Studies show that obesity is linked to a higher risk of COVID-19 complications. "The research findings show that patients with obesity who achieved substantial and sustained weight loss with bariatric surgery prior to a COVID-19 infection reduced their risk of developing severe illness by 60 percent," says Ali Aminian, MD, director of Cleveland Clinic's Bariatric & Metabolic Institute. "Our study provides strong evidence that obesity is a modifiable risk factor for COVID-19 that can be improved through a successful weight-loss intervention."


Bad Diet

pile of unhealthy junk foods

There's no getting away from it: If you eat an unhealthy diet heavy in junk food, sugar, and processed carbohydrates, obesity is practically a given. "Studies show again and again that we humans have a great tendency to underestimate what we have eaten during the day and tend to minimize the calories in the foods that we eat," says Kristen A. Carter M.S. "Often individuals seeking to lose weight are asked to keep a food diary before they even start."


Ferozan Mast
Ferozan Mast is a science, health and wellness writer with a passion for making science and research-backed information accessible to a general audience. Read more about Ferozan
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