New research says dairy milk may help protect older adults from aging.
A study published Monday says drinking three cups of dairy milk a day boosts an antioxidant that helps protect the brain from damage related to cognitive decline.
The University of Kansas Medical Center faculty published the study in the international journal Frontiers in Nutrition.
"Just like an old car that rusts, 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, as it’s called, is thought to be a major mechanism of brain aging. Drinking dairy milk may fight that rust," KU Medical Center said in a press release Monday.
How was the study organized organized
- One group of older adults was asked to drink three cups of 1% milk a day
- A control group not to change their consumption habits. (The typical American adult over age 60 drinks less than two cups of milk per day, according to data from the Centers for Disease Control and Prevention.)
- The group that had increased milk consumption boosted glutathione (GSH) levels significantly.
GSH is a powerful antioxidant that helps protect the brain from some of the damage that accompanies aging and aging-related diseases.
While there was no change in the levels of GSH in the brains of the participants in the control group, the group that drank three cups of 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.
“It's exciting that something as simple as drinking milk can increase GSH because it’s not a drug, it’s just a simple food,” Ph.D., RD, professor and chair of the Department of Dietetics and Nutrition in the KU School of Health Professions at KU Medical Center Debra Sullivan said. “And the three cups a day is actually what is recommended by the U.S. Dietary Guidelines.”
The study builds on work that Sullivan began over a decade ago with Ph.D. In-Young Choi, the study's lead author and director of the Metabolic Imaging Unit and the Magnetic Resonance Science Program at the Hoglund Biomedical Imaging Center at KU Medical Center.
Sullivan says she approached Choi about collaborating and using her brain antioxidant scanning technique to measure how people's eating affects their brains. Sullivan was also an author of the study.
When they completed their first exploratory study, Choi says they were surprised by the results.
“I was thinking fruits and vegetables would be highly correlated with antioxidants in the brain,” Choi said. “But instead, it was dairy, and among the dairy foods, it was milk. That was really surprising.”
The researchers then applied for and were awarded a grant from the National Dairy Council. The National Institutes of Health also grants funds to the imaging center.
KU Med says these funders have no input on the study design, data or the interpretation of the information.
In 2015, Choi and Sullivan and their team published an observational study in the American Journal of Clinical Nutrition that again found that milk was highly correlated with concentrations of GSH in the brain of older adults.
Choi noted earlier findings show that GSH levels are lower in older adults, about 10%.
What remains to be discovered is the specific mechanisms by which milk increases levels of GSH in the brain.
The researchers plan to conduct more studies to measure if milk leads to measurable changes in brain function, if so, the optimal dose of milk, and if the amount of milk fat matters.
In the meantime, there's no reason not to drink up