A diet that limits added glutamate, a flavor enhancer commonly found in many packaged and ultraprocessed foods, may help ease migraines and shift brain structure, according to early research presented at the Society for Neuroscience annual meeting. The findings have not yet been peer-reviewed, but they point to a possible low-cost option for veterans with Gulf War Illness, a chronic condition affecting more than a quarter of those who served in the 1990–1991 Gulf War.
Scientists from Georgetown University and American University found that veterans who followed a low-glutamate diet for one month had fewer migraines and showed changes in cortical thickness, a brain measurement previously linked to migraine activity.
“This was exciting, because it shows that the brain itself is responding and changing,” said senior author Ashley VanMeter, PhD. “This isn’t a psychological reaction. These are actual changes in the brain related to the diet.”
Before shifting their eating pattern, veterans with Gulf War Illness showed increased cortical thickness in the right visual cortex compared with healthy participants and were far more likely to report migraines. After one month on the low-glutamate diet, cortical thickness decreased and migraine frequency dropped.
“More than half of the Gulf War veterans had migraines before the diet, and that dropped to under 20% after following the diet for one month,” VanMeter said. “So it was a very significant drop.”
The diet aims to lower exposure to added glutamate from food additives such as MSG, hydrolyzed proteins and yeast extracts. These appear most often in snack foods, frozen meals and other highly flavored processed products. Naturally occurring glutamate in foods like tomatoes, mushrooms and Parmesan cheese is not restricted. Glutamate acts as an excitatory neurotransmitter, and some people may be more sensitive to excessive levels from additives.
Study co-author Kathleen Holton, PhD, MPH, said the findings support the team’s view that glutamate could contribute to symptoms by driving excitotoxicity, inflammation and oxidative stress.
“We think this is one of the reasons people who are susceptible to dietary glutamate tend to have prolonged symptoms over time,” she explained.
Although this work focused on Gulf War veterans, cortical thickening is also common among people with migraines in general. The researchers are now studying whether similar benefits appear in broader migraine populations.
“This is a very doable diet,” VanMeter said. “It’s a healthy diet, it’s not that hard to follow and it’s a very low-cost way of treating what for some individuals is a chronic and debilitating condition.”
Holton noted that the findings also add to research on how certain ultraprocessed foods may affect neurological symptoms, particularly for people sensitive to flavor-enhancing additives.
“This speaks to the fact that diet can not only make us sick, but can also acutely treat our symptoms,” she said.
More studies are underway, including work exploring whether changes in the blood–brain barrier play a role in glutamate sensitivity.
This research was funded by the U.S. Department of Defense. The authors report no personal financial conflicts.