Fatty Foods Can Damage the Brain, Study Says

Eating unhealthy and fatty foods have negative effects on our health, and a new study suggested that it also negatively impacts the brain.

Science Daily reported that the research, which is published in the journal Brain, Behavior and Immunity, revealed that a high-fat diet damages the brains synapses that could lead to memory and learning impairment.

Medical News Today cited that "a high-fat diet destroys synapses -- connections that aid communication between neurons, or brain cells -- in the hippocampus of the brain, which may impair learning and memory."

Nonetheless, the researchers emphasized that the damaging effects of a high-fat diet can be countered and fixed thorough returning and maintaining a low-fat diet.

In order to reach this conclusion, the researchers experimented on two groups of mice, one of which were fed with a diet that contains 10 percent of calories from saturated fat while the other was fed with food that contains 60 percent fat. They highlighted that the types of diet used for the mice represents a healthy diet and a fast-food diet in humans.

During the fourth, eight, and 12th week of the experiment, the researchers assessed the weight, food intake, insulin level and blood glucose level of the two groups of mice.

The levels of "synaptic markers" are the same on both groups during the fourth and eight week. However, during the 12th week, the researchers found that the synaptic markers of the group of mice fed with high-fat diet had decreased while cytokine levels increased, suggesting that synapses were damaged in the hippocampus.

According to the researchers, too much fat in the body leads to "chronic inflammation" which then activates a response from the microglia -- a type of glial cell that act as the first and main form active immune defense of the central nervous system.

"Normally in the brain, microglia are constantly moving around. They are always moving around their little fingers and processes. What happens in obesity is they stop moving. They draw in all their processes; they basically just sit there and start eating synapses. When microglia start eating synapses, the mice don't learn as effectively," Dr. Alexis M. Stranahan, neuroscientist in the Department of Neuroscience and Regenerative Medicine at the Medical College of Georgia and the corresponding author of the study, said.

On the other hand, when the researchers switched the diet of half of the mice in the high-fat diet group to low-fat diet, they found that after around two months, the synaptic function were restored among those that were switched while those that remained at the high-fat diet continue to gain weight and lose synapses.

The researchers believe that this finding is very promising as it suggests that existing drugs used for conditions such as rheumatoid arthritis and Crohn's disease can also be used to treat conditions that involve synaptic loss.