For many years, scientists have known that what harms the body can also harm the brain.
Problems like obesity, high blood pressure, and insulin resistance put extra stress on the body, and over time, this stress can lead to cognitive decline and even raise the risk of Alzheimer’s disease.
But now, researchers at Arizona State University and their partners have discovered that some of these harmful effects may begin much earlier in life than previously believed.
In a new study, scientists looked at young adults with obesity and found warning signs in their blood that suggest early brain stress.
These changes included signs of inflammation, stress in the liver, and signs that brain cells might already be getting damaged.
These early markers are often seen in older adults with memory problems, making it a surprising and concerning finding in much younger people.
The study, published in the journal Aging and Disease, also found something unexpected: young adults with obesity had very low levels of choline, an important nutrient that supports brain health, liver function, and inflammation control.
Choline is an essential nutrient, meaning the body needs it but can’t make enough on its own. People get most of their choline through food. Foods rich in choline include eggs, fish, chicken, beans, and vegetables like broccoli and cauliflower.
Despite its importance, many people—especially teenagers and young adults—do not get enough choline in their daily diets. The study found that women had especially low levels, which is important because Alzheimer’s disease affects women more often than men.
The researchers studied 30 young adults in their 20s and 30s—half with obesity and half with healthy body weight. They measured blood levels of choline, signs of inflammation, blood sugar and insulin, liver enzymes, and a brain protein called neurofilament light chain (NfL).
NfL is released when brain cells are damaged and is considered an early warning sign of conditions like Alzheimer’s.
The young adults with obesity had more inflammation, higher liver stress, more signs of insulin resistance, and higher levels of NfL. At the same time, they had much lower levels of choline. This pattern is similar to what is seen in older adults with memory issues, even though these participants had no symptoms yet.
The researchers also compared their findings with data from older adults who had mild cognitive impairment or Alzheimer’s disease—and the same pattern of low choline and high NfL was found.
This suggests that brain stress related to obesity might start silently in early adulthood, long before people notice any problems with thinking or memory. The findings highlight how obesity, inflammation, and poor nutrition may work together to affect the brain early on, increasing the risk of problems later in life.
One concern is that some of the new weight-loss medications, such as GLP-1 drugs, reduce appetite so much that people may not eat enough of the nutrients they need—including choline. This could make things worse unless patients also take steps to ensure their diets remain balanced.
Although the study does not prove that obesity causes brain damage, it does show a strong link between low choline, obesity, and early signs of stress in the brain. It supports earlier animal studies showing that a lack of dietary choline can lead to obesity and signs of Alzheimer’s in mice.
The researchers say that maintaining a healthy metabolism and eating enough choline may help protect the brain starting in early adulthood. More research is needed, but these findings may offer new ways to reduce the risk of brain aging and memory loss later in life.
If you care about brain health ,please read studies about Vitamin B9 deficiency linked to higher dementia risk, and cranberries could help boost memory.
For more health information, please see recent studies about heartburn drugs that could increase risk of dementia, and results showing this MIND diet may protect your cognitive function, prevent dementia.
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