Humans have been adding salt to our food for thousands of years and for good reason: It makes just about everything taste better. Not saltier—just better. Why else would people put it on foods like grapefruit, watermelon, cheese, and caramel? Salt works its magic in several ways. First, it suppresses bitter tastes, which allows the food’s other flavors to come out. Second, it helps food release molecules (called volatile compounds) into the air, making that food easier to smell. And we all know how important our sense of smell is to our ability to taste. (Remember when you were a kid, how you’d hold your nose when taking medicine or when your parents forced you to try a new food that you thought you wouldn’t like?) In a fascinating new study published in the journal Proceedings of the National Academy of Sciences (PNAS), researchers at Penn State discovered that there’s another way to move those volatile compounds from the foods you eat into your nasal passage: slow, even breathing. The researchers (actually a team of mechanical engineers) used a 3D printer to create a model of the human airway to see how air flows between the nostrils and the trachea (the windpipe). The process is beautifully complex. When we chew, particles of food end up at the back of the mouth. Inhaling through the nose creates a kind of wind barrier that keeps volatile compounds from getting pulled in the wrong direction (to get the most flavor out of our food, we want the volatile compounds to move forward into the nasal passages, rather than backward into the lungs). Exhaling through the nose sweeps up those volatile compounds and channels them to the nasal cavity, where the olfactory cells process them and send the information on to the brain. However, this process works only if you breathe the right way. Several studies have found that those who eat slowly consume less than those who eat more quickly. Eating slowly makes the food taste better and gives your body a chance to feel full, which, in turn, reduces the amount of food you’ll consume and increases the amount of food you’ll leave behind, or waste. Interestingly, while breathing slowly is important, breathing too slowly also disrupts the airflow. That volatile-trapping wind barrier doesn’t form, and the volatile compounds get sucked away from your nose. Makes sense, doesn’t it? Wolfing down your food so quickly that you aren’t giving yourself a chance to breathe disturbs that perfectly constructed airflow and allows the food volatiles escape. The result? Your food doesn’t taste as good. And that’s incredibly important. In this way, eating too quickly can also work against you. If you’re someone who tends to eat too much too quickly, chances are you aren’t fully enjoying the taste of your food. You’ll probably eat faster in an attempt to take in more flavor. And if you’re someone who doesn’t have time to properly enjoy your meal, you’ll probably, once again, leave some of that tasteless food on your plate.
Goldilocks breathing: not too fast, not too slow. “Smooth, relatively slow breathing maximizes delivery of the particles to the nose,” says Rui Ni, the Penn State study’s lead author. “Food smells and tastes better if you take your time.”