A new study on rats has discovered that obesity may do more than just add fat to your midsection and other body organs. Terry Davidson, director of American University’s Center for Behavioral Neuroscience, discovered that high saturated fat and refined sugar diets changed the brains of rats, making the rats desire more of the unhealthy products.
“It is a vicious cycle that may explain why obesity is so difficult to overcome,” said Davidson. The research is published in the journal Physiology & Behavior.
Davidson’s research focuses on the hippocampus—the part of the brain responsible for memory and learning.
For the current study, Davidson and his team trained rats given restricted access to low-fat “lab chow” on two problems — one that tested the rats’ hippocampal-dependent learning and memory abilities and one that did not.
Once the training phase completed, the rats were split into two groups: one group had unlimited access to the low-fat lab chow, while the other had unlimited access to high-energy (high-fat/calorie) food.
The high-energy food was high in saturated fat (animal fats, such as those found in cheese or meat or certain plant-based fats, such as cottonseed oil and coconut oil)—considered to be the most unhealthful dietary fat as research has linked it to cardiovascular disease and certain types of cancer.
When both groups of rats were presented the problems again, the rats that became obese from the high-energy diet performed much more poorly than the non-obese rats did on the problem designed to test hippocampal-dependent learning and memory.