More: 4 Common Dieting Mistakes That Make You Fat
After eight weeks on the program, the high-fat group was obese but had brain health equal to the low-fat group's. However, come week 12, that all started to change.
At the three-month mark, the high-fat eaters began to experience cognitive issues, and their microglia—healthy cells in the brain that are known for their ability to rid the brain of trash and infections—began to overconsume.
"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," said Alexis M. Stranahan, PhD, a neuroscientist with the department of neuroscience and regenerative medicine at the Medical College of Georgia and the lead author of the study. "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."
More: 8 Things to Know Before Ordering Your Next Fast Food Meal
Those powerful cells that can keep your brain healthy go on a ravenous eating rampage.
"Instead of doing garbage disposal, they are taking your mailbox, your front door, your kitchen sink, and all the stuff that you need," Stranahan added. "[They're] not doing their job of getting rid of trash."
Luckily, cutting the saturated fat can help the brain—and obesity—improve. After 12 weeks, the researchers switched half the mice on the 60 percent saturated-fat diet to the lower (10 percent) saturated-fat diet. The mice returned to their normal weight in two months. However, these mice did develop a fat layer that would make it easier for them to gain weight again in the future.
While the study authors note that the results cannot be necessarily translated to humans, that's no reason not to cut back on saturated fats. From their weight-increasing effects to their cholesterol-raising impact, these fats have some pretty adverse health effects you definitely want to avoid. And now it appears that cutting back on them may also help save your brain.