- A new study explores the connection between obesity and Alzheimer’s disease.
- Researchers found different cellular messengers in people with obesity that signal plaque formation in the brain.
- Here’s what this means for you, according to doctors.
Scientists still don’t know exactly what causes Alzheimer’s disease. But as more and more research funnels in, there are lots of new theories and datapoints trying to draw a clear picture of the devastating disease. Now, there’s another factor to consider: New research suggests that obesity could fuel Alzheimer’s progression.
While obesity has been linked to a range of serious health conditions like heart disease and type 2 diabetes, the Alzheimer’s disease connection is new. It’s important to point out that the researchers didn’t find that having obesity causes Alzheimer’s disease—they just found a link. But it raises a lot of questions about why the two might be connected.
Here’s what a neurologist and obesity medicine specialist want you to keep in mind when trying to parse this study.
Meet the experts: Clifford Segil, DO, a neurologist at Providence Saint John’s Health Center in Santa Monica, CA; Mir Ali, MD, medical director of MemorialCare Surgical Weight Loss Center at Orange Coast Medical Center in Fountain Valley, CA
What did the study find?
For the study, which was published in the journal Alzheimer’s & Dementia, researchers isolated something called extracellular vesicles from fat cells. These vesicles are cell-to-cell messengers in the body and they can signal the buildup of amyloid-β plaque—a key feature of Alzheimer’s disease—in people with obesity.
The study gets very technical, but the researchers basically discovered that the fat composition in these cell messengers is different in people with obesity. The obesity factor was also correlated with how quickly amyloid-β clumped together in lab models.
Based on their findings, the researchers suggest that targeting these little cellular messengers and interrupting their plaque-building signals may help lower the risk of Alzheimer’s disease in people with obesity.
Why is obesity linked with Alzheimer’s?
It’s not entirely clear. The researchers simply found a link between the way certain cells act in people with obesity and the potential formation of plaques in the brain. But so far, there’s no evidence that obesity causes Alzheimer’s disease.
“This is a novel idea and obesity in the past has not been considered a modifiable risk factor for memory loss,” says Clifford Segil, DO, a neurologist at Providence Saint John’s Health Center in Santa Monica, CA.
There could be a few reasons for this link, though. “This study provides a potential explanation that perhaps fat cells are releasing substances that are being transported to the brain, causing a buildup of amyloid plaques that can contribute to Alzheimer’s disease,” says Mir Ali, MD, medical director of MemorialCare Surgical Weight Loss Center at Orange Coast Medical Center in Fountain Valley, CA. But he stresses that more research is needed to learn more about this connection.
“Chronic inflammation caused by obesity could impact the brain as well,” Dr. Ali says. “But nobody is 100 percent sure.”
What are extracellular vesicles and what role do they play in the body?
Extracellular vesicles are tiny particles that travel throughout the body and act as messengers in cell-to-cell communication. They are capable of crossing the blood-brain barrier which means they can interact directly with receptors in the brain.
“A certain amount of fat or lipids are necessary for our body to work well,” Dr. Segil explains. “Many chemicals in our bodies are bundled into small packages and produced in one part and then used in another part of the body. These packages that these substances are transported in around the body requires a [fat] outer membrane to being transported and these packages are called ‘vesicles.’”
What can I do to reduce my risk of developing Alzheimer’s?
Dr. Segil points out that having obesity is an “unclear” risk factor for Alzheimer’s disease. However, it is a risk factor for diabetes, heart disease, and stroke.
With that, Dr. Ali recommends doing what you can to maintain a healthy weight by eating a varied diet and exercising regularly. If that doesn’t help, he suggests talking to your healthcare provider about next steps. “There are a lot of option to help,” he says.
To lower your risk of dementia in particular, Dr. Segil recommends doing what you can to eat a healthy diet and get in daily exercise. He also suggests keeping your brain “busy” as much as possible. That means socializing regularly, and pushing yourself to learn new things.
Korin Miller is a freelance writer specializing in general wellness, sexual health and relationships, and lifestyle trends, with work appearing in Men’s Health, Women’s Health, Self, Glamour, and more. She has a master’s degree from American University, lives by the beach, and hopes to own a teacup pig and taco truck one day.