Scientists Say Fat Can Actually Eat Your Brain

Mauricio Lima/AFP/Getty Images

Mauricio Lima/AFP/Getty Images

High levels of body fat aren’t good for you — that shouldn’t be news to anyone. Scientists are seemingly finding more and more ways in which obesity hurts us on a weekly basis. For example, we now know that body fat has the ability to actually reprogram our bodies to work against us. And if that isn’t worrisome enough, fat can be deceptive — finding ways to encourage our brains and bodies to crave it, despite knowing that it’s harmful.

It’s nasty stuff. And the more we learn about it, the nastier it gets. A new study cranks the nasty up to 11.

According to researchers at the Medical College of Georgia at Georgia Regents University, fat can eat your brain. Well, it’s not that simple, but something similar is happening. A new study says that in people who eat a high-fat diet, and become obese as a result, immune cells present in the brain are effectively hijacked — they become sedentary and turn on healthy tissue.

Specifically, those hijacked or reprogrammed cells start to consume our neuron connections. These are the connections that send signals to and fro throughout our brains. Basically, it’s how we think. How we function. And if this study is an indication, obesity may be just as bad for our cognitive health as it is for the rest of our body.

“Microglia eating synapses is contributing to synapse loss and cognitive impairment in obesity,” said Dr. Alexis M. Stranahan, a neuroscientist in the Department of Neuroscience and Regenerative Medicine at the Medical College of Georgia. Stranahan was quick to offer up just how horrifying all of this sounds. But there is a silver lining.

“On the one hand, that is very scary,” he said. “But it’s also reversible, meaning that if you go back on a low-fat diet that does not even completely wipe out the adiposity, you can completely reverse these cellular processes in the brain and maintain cognition.”

So there you have it. Through an unhealthy, high-fat diet, you can create the conditions for which your brain cells start munching on your neurons. But you can also reverse it. The problem is that it’s harder to lose weight than it is to gain weight, in most cases, and knowing that obesity already does a bit of “reprogramming” to our body can make it that much harder.

This particular study, like many others, used mice to study the impacts of high-fat diets and resulting levels of adipose tissue. As the researchers explain it, the mice in question saw a measurable impact in cognitive function; that is, they weren’t able to learn as effectively. The reason why has to do with microglia cells, which typically cruise around our bodies, taking care of “trash.” They’re essentially our body’s custodians.

But when we become obese, it bogs down these cells, and they stop moving around. When they stop looking for junk to consume, they start consuming what’s around them. In the case of the cells in our brain, they go after neuron connections. A sedentary lifestyle translates right to our cells, interestingly enough.

You shouldn’t necessarily panic about brain-eating fat cells, at least not yet. There is a lot of research to do to further investigate the link between obesity and cognitive health. Though you shouldn’t hit the panic button, the message here is pretty clear: Staying in shape is going to help you stay sharp. There are plenty of studies that back this notion up, and one of the key ways to keep up our cognitive health as we age is to maintain an all-around high level of fitness.

This gets harder as we get older, as our bodies naturally lose the ability to bounce back with the same level of quickness and vigor as when we were younger. Many people find it harder to squeeze workouts in, with mounting work and family responsibilities, and even maintaining a healthy diet can be a challenge. But the more we learn about obesity and fitness, the more obvious it is that we’re going to need to find ways to make fitness a priority, as hard as it may be.

If having a long life isn’t enough to get you jogging and eating celery, is the thought of synapse-destroying macrophages taking a proverbial baseball bat to your brain?

Follow Sam on Twitter @Sliceofginger

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