Our food environment has changed dramatically over the years, most notably through the introduction of so-called "hyperpalatable" foods. These foods are deliberately engineered in such a way that they surpass the reward properties of traditional foods, such as vegetables, fruits, and nuts. Food chemists achieve this by suffusing products with increased levels of fat, sugar, flavors, and food additives.
David A. Kessler, author of The End of Overeating: Taking Control of the Insatiable American Appetite and former head of the FDA, claims that the food industry has combined and created foods in a way that taps into our brain circuitry, thus stimulating our desire for more. On their own, these ingredients aren't particularly potent, but when combined in specific ways, they tap into the brain's reward system, creating a feedback loop that stimulates our desire to eat and leaves us wanting more - even when we're full.
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