Thoroughly chewing your food forces you to eat slowly and gives your body time to feel full. It gives your brain time to register that you have eaten enough food before you overeat. This is part of the reason why people who eat slowly are less likely to be overweight than people who eat fast.
Thoroughly chewing your food makes it easier for your digestive system to completely digest the food that you eat. Digestion begins in your mouth with enzymes in your saliva (a-amylase and lipase) that digest carbohydrates and fats. The more you chew your food, the more of your food you expose to the enzymes and the more completely the food gets digested.
More nutrients become available for absorption with more complete digestion. And as a result, your body absorbs more nutrients. Internal sensors in your gut tell your brain when you have enough nutrients and are satiated, which turns off your hunger signal. The more nutrients you can get out of your food, the less food you have to eat to feel satisfied. Research has shown that less ghrelin, a hormone responsible for feeling hunger, is released the more food is chewed, which makes you feel satisfied longer.
High-fiber foods such as fruits, vegetables, nuts, and seeds force you to chew more and eat more slowly by the very nature of these foods. This is because your body cannot digest the fiber in these foods, so chewing is the only way your body can break down these high fiber foods and access their nutrients.
How many times should you chew each bite of food? It’s not really necessary to count how many times you chew each bite because not all foods require the same number of chews to be chewed thoroughly. A good rule of thumb is to chew until you can no longer feel the texture of the food in your mouth. That’s when you know it’s time to swallow.
I've been consciously trying to break my own bad habit of eating fast without properly chewing my food, and I’ll tell you, not only do my jaw muscles feel like they've been through a workout at the gym after every meal, it takes me significantly longer to eat my food! I find it very helpful to put my fork, spoon, or chop sticks down after every bite of food. When I don’t have the next bite loaded up and ready to go into my mouth, I don’t feel the need to rush and swallow without chewing properly. I also found that I was forced to take smaller bites because my normal bite had too much food to keep in my mouth long enough to properly chew before swallowing, and some of that excess food slipped down my throat only partially chewed. And I’ve noticed that by the time I’m half to three quarters of the way through a standard-sized meal that I normally consume, I’m already full! So if you’re trying to lose weight, this is a great way to control how much you eat without feeling hungry.