Eating high-fat, high-sugar foods can change our brains to prefer sweets

Eating high amounts of certain foods can contribute to specific health conditions.

ISLAMABAD, (Online) - Consuming a Western diet high in sugar and fat poses many health risks. But often, these foods are easier to crave and consume.

A recent study published in Cell Metabolism examined how eating high-fat and high-sugar foods alters the brain’s reward centers.

Researchers found that participants who consumed high-fat and sugar yogurt had less of a desire for low-fat foods and had an increased brain response to high-fat and sugar foods. The results suggest the importance of food choices in maintaining a healthy body weight.

Dangers of eating foods high in fat and sugar

Eating food is how people get the nutrients they need for survival. Most diets will contain some fat and sugar, which is often necessary. However, eating high amounts of certain foods can contribute to specific health conditions.

Foods high in saturated fat can increase stroke and heart disease risk. The American Heart Association (AHA) suggests people should limit their intake of food high in saturated fats, like butter, ice cream, and fried foods. Similarly, sugar occurs naturally in some foods but can be added in excess to others. Too much sugar can increase the risk of diabetes, weight gain, and heart disease.

Barbara Kovalenko, non-study author and registered dietitian and nutrition consultant at Lasta, explained to Medical News Today:

“Consuming foods high in fat and sugar on a regular basis can have several negative effects on your health. Foods high in saturated and trans fats can contribute to high cholesterol levels and increase the risk of heart disease; whole foods high in sugar can lead to weight gain, tooth decay, and an increased risk of developing type 2 diabetes…It's important to keep in mind that not all fats and sugars are bad for you, but consuming them in excess can be harmful. A balanced diet that includes a variety of nutrient-dense foods is key for optimal health.”

Choosing healthier food options can be challenging, even when people know the benefits of eating foods that are lower in sugar and fat. Researchers are still working to understand the relationship between food choices and brain changes, one of this study’s main points of interest.

How brains change to prefer fat and sugar

Study author Dr. Marc Tittgemeyer with the Max-Planck-Institute for Metabolism Research explained the goals of this study to MNT:

“Work in rodents has shown that diet alone can change preference and rewire brain circuits. We wanted to understand if diet alone (in the absence of weight gain) might cause changes in preference and rewire brain circuits in humans.”

The study was a randomized, controlled study involving fifty-seven individuals who were not overweight. Researchers wanted to look at the impact of food choices on the dopaminergic systemTrusted Source, a pathway in the brain that is involved in motivation and reward behavior.

Researchers divided participants into two groups. Over eight weeks, the first group received high-fat, high-sugar yogurt twice daily. In contrast, the second group received low-fat, low-sugar yogurt twice daily. Other than this, the groups continued on their regular diet.

In both groups, weight and metabolic parameters remained about the same. However, other changes did occur. Participants who had eaten high-fat, high-sugar yogurt had a much lower preference for low-fat foods than those who had eaten low-fat, low-sugar yogurt. The high-fat, high-sugar group also had increased brain responses when anticipating and consuming milkshakes.

Dr. Tittgemeyer explained the key takeaways of the study’s findings:

“Our study demonstrates that short term daily consumption of (high-fat/high-sugar) snacks reduces preference for a low-fat food and rewires brain reward circuits to enhance response to palatable food…Surprising was that the high fat/sugar snack not only rewired brain circuits responding to food but also brain circuits critical for learning in general. Also, these effects occur without weight gain.”

Non-study author Kelsey Costa, a Registered Dietitian Nutritionist from Dayville, CT, further commented with her thoughts on the study’s findings:

“The research indicates that exposure to an unhealthy diet due to lack of access to healthy foods may alter physiology, even in healthy-weight individuals, resulting in adaptations that create a preference for unhealthy foods and promote overeating. This study suggests that the food environment we live in has a profound impact on our eating habits, rather than individuals being solely responsible for their dietary choices.”