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Humans, like animals, have an obesity “switch” researchers say

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11min 06sec
Andrea Dukakis/CPR News
The book, “Nature Wants Us to Be Fat,” traces the roots of obesity to animals in nature.

The new book, “Nature Wants Us to Be Fat,” follows efforts by researchers to understand why people gain weight and become obese. Dr. Richard Johnson, a professor at the University of Colorado School of Medicine, and his team hypothesized that the reasons behind obesity can be traced back to animals in nature and then tested their theories in the lab.

They found that while animals normally regulate their weight well, there is a biological “switch” that triggers not only the development of obesity, but also causes prediabetes and increased blood pressure. This switch is used by animals in the wild to prepare for hibernation. Bears do this by eating lots of berries that are high in fructose, which is a type of sugar. 

Dr. Johnson and his researchers found that humans also trigger this switch, which, as in animals, plays a key role in the development of obesity and diabetes. According to the research, humans trigger the switch by eating a lot of sugar and high fructose corn syrup. The fructose lowers the energy in our cells which acts as an alarm signal and prompts us to store fat. 

Foods from starchy and salty foods can also activate this biological “switch” but Johnson says people can avoid triggering the switch by sticking to a low-sugar, low-salt diet, drinking 6-8 glasses of water a day, and avoiding high-glycemic foods like bread, potatoes and rice.