Are you having a hard time stopping yourself from having another bowl of ice cream? The reason may be in you genes. A group of UK researchers have revealed that a person's love for high-fat food may already be hardwired in the brain.
Researchers form the Imperial College London found at least two genetic variants of DRD2 and FTO could contribute to a person's persistent craving for high-calorie food. FTO increases the person's disposition to obesity while DRD2 changes the signal of dopamine, a neurotransmitter that is linked to pleasant sensations and rewards, such that when people with the variants are provided with salty or fatty food, their craving becomes intensified. In the process, they tend to eat more of these kinds of food.
For the study, the researchers recruited more than 40 men of European Caucasian descent. After fasting overnight, they were presented with a series of pictures showing high-calorie and healthy food and were asked the level of appeal of each of the pictures. Each of the participants was also connected to an fMRI (functional magnetic resonance imaging) to assess their brain activity during the experiment and their DNA sample taken for study.
According to the results, people with the FTO gene variant had a higher brain activity when shown with photos of high-calorie food, which could indicate these types of food appeal more than the healthy ones. The level of activity was especially pronounced in the part of the brain known as striatum, which is part of a dopaminergic pathway, but it may vary depending on the exact DRD2 variant the person had. Either way, the researchers believed that a possible reason why people with the FTO variant tend to become obese is because they also had the DRD2 variant, which alters the way dopamine works in the brain, heightening their sensation of rewards from high-calorie food.
The findings, which were shared in a Los Angeles annual meeting of Obese Society on Thursday, Nov 5, may change the way obese people with these variants can be treated including use of medications that affect dopamine levels, hormonal intervention, and surgery.