When I was growing up, my mother always told me and my brother, “Drink your milk.” Turns out, Mom was right!

Several studies have linked adults drinking cow’s milk to a lower risk of dementia including Alzheimer’s disease. After analyzing the studies, researchers have concluded that drinking milk improves cognitive function and sustains memory in adults.

According to the American Geriatrics Society, milk from cows produces an antioxidant called glutathione (GSH). When this antioxidant flows through the body, it soothes oxidative stress in the brain. This keeps the brain healthy with sharper memory and quicker learning function.

Drink 3 cups of milk daily

Scientists at the University of Kansas Medical Center found that adults drinking three 8-ounce glasses of cow’s milk every day can positively influence the production of glutathione in your brain, which in turn can protect the brain from some of the damage caused by aging and aging-related diseases.

“Just this simple drinking of milk was able to raise that antioxidant level up in these older adults, which is impressive from a single food you can buy at the grocery store,” says Debra Sullivan, Ph.D., professor and chair of the Department of Dietetics and Nutrition in the KU School of Health Professions. Sullivan is an author on the study, which was published in August 2022 in Frontiers in Nutrition.

Like an old rusting car, the human brain becomes corroded over time by free radicals and other oxidants that are released as the brain converts nutrients into energy. This oxidative stress is believed to be a major mechanism of brain aging, as well as many neurodegenerative diseases including Alzheimer’s and Parkinson’s disease. GSH helps stave off oxidative stress and the damage it causes. But, according to the authors of the study, as people age, their levels of brain GSH tend to drop.

U.S. Dietary Guidelines

The U.S. Dietary Guidelines recommends that adults drink 3 cups of milk a day, but according to data from the Centers for Disease Control and Prevention, the typical American adult over age 60 drinks less than 2 cups of milk per day.

Sullivan became interested in studying GSH and brain health more than a decade ago.

In her study, 73 adults between the ages of 60 and 89 who typically consumed less than 1.5 servings of dairy per day were randomly assigned to either a control group, which did not alter its usual milk intake, or an intervention group, which increased their milk intake to 3 cups per day for three months. The study provided the participants in the intervention group with low-fat 1% milk. For participants in both groups, brain antioxidant imaging scans were conducted at baseline and after three months.

While there was no change in the levels of GSH in the brains of the participants in the control group, the group that drank 3 cups of dairy milk a day saw their brain GSH levels increase by an average of nearly 5% overall, and by more than 7% in the parietal region of the brain. Earlier findings have shown that GSH levels are lower in older adults by about 10%. 

Moreover, the daily 3 cups of milk that increased the levels of brain GSH is already the amount recommended for adults by the U.S. Dietary Guidelines. The “side effects” when an older person begins drinking this much milk to protect the brain include helping to increase their muscle mass and preventing them from developing osteoporosis and breaking bones.

“Milk has a great package of nutrients. It’s important for your brain health, your bone health, your muscle health — all of those things,” Sullivan says. “That’s the takeaway.”

So, if you want to improve your memory and your overall health, do what Mom said and “drink your milk.”