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Researchers show that the reward center of the brain values foods high in both fat and carbohydrates-processed foods more than foods containing only fat or only carbs. A study of 206 adults, supports the idea that these kinds of foods hijack body’s inborn signals governing food consumption.
According to Dana Small, director of Yale University’s Modern Diet and Physiology Research Center, the biological process that regulates the association of foods with their nutritional value evolved to carefully define the value of a food so that organisms can make adaptive decisions.
Foods containing fats and carbohydrates signal their potential caloric loads to the brain via distinct mechanisms. Participants were very accurate at estimating calories from fat and very poor at estimating calories from carbohydrate.
The study shows that when both nutrients are combined, the brain seems to overestimate the energetic value of the food. During the research, test subjects underwent brain scans while being shown photographs of familiar snacks containing mostly fat, mostly sugar, and a combination of fat and carbs.
In the past, people ate woody plants and animal meat. Foods high in fat and carbohydrate are very rare and tend to have fiber, which slows metabolism but it is very common for processed foods to have high fat and high carbohydrate. Domestication of plants, animals, the development of grain and dairy production lead to consumption of fat and carbohydrates
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