Your body’s survival mechanisms have evolved to fight starvation because, for most of human history, starvation has been a greater threat to survival than obesity.
“Over the course of history, starvation has been a much bigger problem than overeating.”
Your hypothalamus area of the brain regulates your weight. It functions like a thermostat; it senses your weight change and alters “hunger, activity and metabolism” accordingly.
“If you lose a lot of weight, your brain reacts as if you were starving, and whether you started out fat or thin, your brain’s response is exactly the same.”
Your hypothalamus works to stabilize your weight at a “set point.” Your body’s perception of your ideal weight is a range of about 10 lb. to 15 lb. [4.5 kg to 6.8 kg].
“You can take control of your health by taking control of your lifestyle, even if you can’t lose weight and keep it off.”
When you lose weight, your hypothalamus perceives starvation and works to help you regain weight. Even after seven years of successful weight loss, the hypothalamus still doesn’t accept your lighter weight as the “new normal.”
“Let’s face it: If diets worked, we’d all be thin already.”
Thus, dieting doesn’t work. Instead, adopt “four healthy habits” – “eating enough fruits and vegetables, exercise three times a week, not smoking, and drinking in moderation” – will help you maintain a healthy body regardless of your weight.
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Neuroscientist & Writer
Sandra Aamodt is a neuroscientist and science writer, who takes the complexities of neuroscience research and whips them into fun reads that give people a better understanding of their minds and behavior. Her books Welcome to Your Brainand Welcome to Your Child's Brain (both written with Sam Wang) are designed to bring neuroscience to a general audience, and they've both been widely translated. Aamodt's science writing has also appeared in The New York Times, The Washington Post, El Mundo and the Times of London.
From 2003 to 2008, Aamodt was the editor-in-chief of Nature Neuroscience, a leading scientific journal in the field of brain research. She brings a significant scientific background to the task of explaining new research without creating neurobunk. During her career, she has read over five thousand neuroscience papers, and written many editorials on science policy.