The high-fat energy-dense diet we consume today is nothing like what humans ate for all of history before us. Luckily, we no longer have to hunt and kill our dinners. Also, jobs today have become much more sedentary than they were historically. All this convenience has produced an energy imbalance between how much energy we consume, and how much energy we expend.
Researchers are still trying to understand all the ways this energy imbalance causes obesity. In 2016 the World Health Organization (WHO) estimated that of the 1.9 billion overweight adults worldwide, 13% are obese. This is nearly triple the number of obese adults in 1975.
Obesity is a risk factor for heart disease, the number one killer worldwide. This is considered a modifiable risk factor or one which can be controlled by implementing lifestyle changes. While it is true that changes to diet and activity level do reduce weight to a healthier level, they work slowly over time. Some high-risk patients may require measures like gastric bypass surgery to bring their weight closer to the normal range before starting a fitness program.
In attempting to understand obesity, researchers discovered a mechanism that prevents fat cells from releasing fat. This mechanism is meant to protect from starvation, and the trigger for the mechanism is the protein receptor for advanced glycation end products (RAGE). The finding comes from NYU’s School of Medicine.
In conducting the study, researchers fed two groups of mice a diet high in fat. From one group, they had removed RAGE from the cells; the other group was an unchanged control.
Both groups got the same amount of exercise and were fed the same diet. Three months after being fed the high-fat diet, the mice without RAGE gained an incredible 75% less weight than the control mice.
A separate study transplanted RAGE-free fat tissues into unaltered mice and found a similar benefit.
Although this mechanism likely developed to defend from starvation, the study indicates that overeating triggers the response as well.
Researchers hope that the development of drugs to block RAGE activity could help people lose weight. Because this protective process results from the immune system, RAGE blockers may also have several uses in controlling the immune response. This could help people with autoimmune conditions.
The above video, from The Infographics Show, contains statistics and facts on obesity.
Sources: Computers in Biology and Medicine, The Infographics Show