To better understand the effects of insulin on the brain, the researchers recruited 29 healthy male volunteers. (Representational image/Pixabay)Splurging on fatty foods such as chocolate bars, crisps, and other junk foods for just five days can lead to lingering changes in brain activity, according to a new study. The resulting brain patterns are similar to those found in people with obesity.The analysis also revealed that these changes occurred despite the body weight and composition remaining the same.The study, ‘A short-term, high-caloric diet has prolonged effects on brain insulin action in men’, was published in the journal Nature on February 21.Stephanie Kullmann, a neuroscientist at the University of Tübingen (Germany) and co-author of the study, told Nature, “I did not expect the effect to be so clear in a healthy population.”How was the study carried out?After we eat something, our body releases insulin to help us break down the food, and some of it reaches our brain to dampen our appetite. However, in people with obesity, the brain’s response to insulin becomes weaker which affects how the body processes food.To better understand the effects of insulin on the brain, the researchers recruited 29 healthy male volunteers. Eighteen of them were put on a high-calorie diet for five days. Their diet comprised 1,500-calorie packs of high-fat, high-sugar snacks. However, the men succeeded in increasing their caloric intake by an average of only 1,200 calories per day.“The researchers imaged blood flow in the participants’ brains as a proxy for brain activity. Imaging was performed before the five-day period, immediately after it and one week later,” according to a report in Nature.What did the study find out?Story continues below this adThe researchers found that after just five days of indulgence, the men’s brains showed higher activity in brain regions that respond to food rewards and dietary changes. These are patterns typically associated with obesity or insulin resistance, which could lead to type 2 diabetes.Also in Explained | What is black plastic — and should you get rid of it?A week after their splurge had ended, the junk-food group had lower brain activity in two regions associated with memory and response to visual food cues.This means that “brain response to insulin can adapt to short-term changes in diet before weight gain and may facilitate the development of obesity and associated diseases,” accordingto study.Kullmann told Nature that the amount of high-calorie food in this study might sound extreme but it is quite similar to what people experience at the holidays.© The Indian Express Pvt LtdTags:Explained Sci-TechExpress Explained