First, some background: Our sense of taste evolved to help us distinguish between good-for-us foods and potentially toxic ones, and each individual taste gives the brain specifics on what a given food will offer, nutritionally. Salty items signal the presence of, well, salt, which is essential for maintaining water balance in the body. Umami lets us know we’re getting amino acids, or proteins. Bitter tastes are often a sign of something poisonous, and sour means you’re getting important dietary acids. Lastly, there’s sweet, which is an indicator of carbohydrates, or sugars, which the brain equates with energy. Receptors on your tongue pick up the different tastes with the help of certain proteins. When that happens, sensory fibers activate centers in the brain involved in taste perception, says Inge Depoortere, PhD, a scientist at the Translational Research Center for Gastrointestinal Disorders in Leuven, Belgium. The result? Sweetness floods your mouth when you eat a piece of chocolate, bitterness when you chomp down on a piece of raw broccoli. But it turns out that taste receptors aren’t just on your tongue. Researchers at Mount Sinai School of Medicine discovered that they’re in your gut, too. It sounds weird, but experts say the discovery of intestinal taste receptors actually makes perfect sense. “We don’t normally think of the mouth as part of the gastrointestinal tract, but it’s the very beginning of that long, continuous tube," says Anthony Sclafani, PhD, a behavioral neuroscientist who studies nutrient sensing in the gut at Brooklyn College. “So in hindsight, it’s not so surprising that receptors in the mouth are also found in the gut.” Of course, the taste receptors in your gut work a little differently than the ones on your tongue. (Could you imagine tasting your turkey sandwich as it moves through your intestinal tract?) While tastebuds on your tongue mobilize the part of your brain that perceives taste, “the tastebuds in your gut turn on an area of the brain involved in feelings of satiation or hunger,” says Dr. Depoortere. Once a taste is recognized in the gut, your brain orders your intestine to ramp up production of hormones that help you process incoming energy, helping you maintain steady blood sugar levels and realize when you’ve had enough to eat. Normally, the process goes off without a hitch. Now, though, researchers are starting to unearth clues about what might be happening when certain taste receptors don’t work as they should—and how that could be hurting us. Compared to those of healthy adults, the sweet taste receptors of adults with type 2 diabetes were shown to trigger the intestine to absorb higher levels of glucose at a faster rate, finds recent research published in the journal Diabetes. “That further increases the demand for glucose disposal in individuals whose ability to do this is already compromised. This, as a result, may worsen diabetic disease,” says study author Richard Young, a senior postdoctoral researcher at the University of Adelaide in Australia. The potential ramifications of faulty taste receptors isn’t limited to diabetes. Another similar study published in the journal Nature suggests that a mutation in the group of intestinal taste receptors responsible for sensing dietary fat (which come from umami taste) could increase your risk for obesity. You don’t need to be obese or have type 2 diabetes to be thinking about the inner workings of your intestinal taste receptors, though. As far as even normal, healthy guts are concerned, some research suggests that sweet taste receptors may not be able to distinguish between real sugars and artificial ones, potentially prompting your gut to release hormones that affect insulin response, Dr. Sclafani says. In other words, even though you know the difference between a diet soda or skinny latte and their sugar-filled counterparts, your body still might not. It could be that these gut taste buds hold the key to obesity, blood glucose control, and more; only time and science will tell. More from Prevention: The Gut And Weight Loss Connection
