Your brain, your stomach, and yogurt

By Alejandro Freixes, CCNN Head Writer

What you eat affects what you think and how you think. Take yogurt, for example. A study at UCLA decided to test the effects of yogurt with probiotics – bacteria that help us digest food and make vitamins – on thinking. What they found, while kind of complicated, points to one simple conclusion: your stomach and your brain have a very close relationship!

The researchers took three groups of 12 women – 36 total – and scanned their brains with functional magnetic resonance imaging (fMRI) while they were relaxing, and also while they were doing an emotional activity (matching angry and frightened faprobiotic yogurtces to other ones with the same emotion). Then, for four weeks, they gave one group yogurt with probiotics, one group a yogurt-like milk product without probiotics, and the third group no yogurt at all twice a day. After four weeks, they did another fMRI comparison between their relaxing – or resting state – and the same emotion-recognition activity.

What did they find? Basically, all three groups had increases and decreases in different areas of brain activity. So, don’t go running to the store to get probiotic food just yet, thinking it’ll make you a genius. Well, you may be asking, what was the point of the study if there was no clear benefit to yogurt with probiotics? It’s surprisingly simple: the fact that all three groups had such different levels of activity in the brain provides evidence that what you eat changes the way your brain reacts to your environment.

Dr. Kirsten Tillisch, an associate professor of medicine at UCLA’s David Geffen School of Medicine and the lead author of the study, says, “Many of us have a container of yogurt in our refrigerator that we may eat for enjoyment, for calcium or because we think it might help our health in other ways. Our findings indicate that some of the contents of yogurt may actually change the way our brain responds to the environment. When we consider the implications of this work, the old sayings ‘you are what you eat’ and ‘gut feelings’ take on new meaning.”