By Pat Anson, Editor

There’s a nugget of truth to the old saying, “You are what you eat.” And no, we don’t mean chicken nuggets. We’re talking turkey.

Researchers at Brigham and Women's Hospital in Boston say changes in diet and gut bacteria appear to influence the activity of brain cells involved in controlling inflammation and neurodegeneration. They’ve published their study in the journal Nature Medicine

"For the first time, we've been able to identify that food has some sort of remote control over central nervous system inflammation," said corresponding author Francisco Quintana, PhD, an investigator in the Ann Romney Center for Neurologic Diseases at Brigham and Women’s Hospital.

"What we eat influences the ability of bacteria in our gut to produce small molecules, some of which are capable of traveling all the way to the brain. This opens up an area that's largely been unknown until now: how the gut controls brain inflammation."

While studying laboratory mice, Quintana and his colleagues found that gut bacteria produce molecules that influence astrocytes -- star-shaped cells that reside in the brain and spinal cord.

The molecules, which are derived from tryptophan (an amino acid found in turkey and other foods), act as fuel that helps the astrocytes limit brain inflammation.

In blood samples from patients with multiple sclerosis (MS) – a disease that attacks the body’s central nervous system -- the researchers found lower levels of these tryptophan-derived molecules.

"Deficits in the gut flora, deficits in the diet or deficits in the ability to uptake these products from the gut flora or transport them from the gut -- any of these may lead to deficits that contribute to disease progression," said Quintana.

MS is a chronic and incurable disease that causes numbness in the limbs, difficulty walking, paralysis, loss of vision, fatigue and pain.

In addition to turkey, tryptophan is found in other high-protein foods such as chicken, beef, nuts and cheese. Its a myth that eating lots of turkey will put you to sleep, according to the American Nutrition Association. But tryptophan does help produce serotonin, a neurotransmitter that regulates mood and mental activity,

Scientists are just beginning to recognize that food and gut bacteria play a role in multiple sclerosis and other chronic pain conditions.

Researchers at New York University’s Langone Medical Center recently found that some intestinal parasites and bacteria play a beneficial role in helping to balance the immune system, and reduce rates of inflammatory bowel diseases (IBD) such as Crohn’s disease and ulcerative colitis.

Sanitary practices have sharply reduced intestinal worm infections in developed nations, which now have some of the highest rates of Crohn’s and colitis. Scientists believe the worms help produce a certain type of bacteria that helps control inflammation. This “hygiene hypothesis” may also apply to MS, rheumatoid arthritis, type 1 diabetes, and other autoimmune diseases.