How Chewing Affects Nutrition
Chewing helps with digestion and weight loss, and affects nutrition in other surprising ways.
Nutrition Diva fan Heather writes:
“A lot of magazine and internet articles recommend chewing each bite of food 30, 40, even up to 80 times. Supposedly, increasing the number of times will help you lose weight. There is even an iPhone app that will track your chews. A colleague of mine also claims there are nutritional benefits to chewing your food extremely well. Is any of this true?”
Although this does sound like one of those nutritional urban legends I’m always debunking, chewing your food more thoroughly can improve digestion, promote weight loss, and affect the nutritional value of foods—in ways you might not expect.
How Chewing Affects Digestion
Digestion does not begin in the stomach but in your mouth—and chewing your food more thoroughly can improve digestion. First, digestive enzymes in your saliva break down starches into simple sugars. In fact, if you chew on a saltine cracker or a bit of bread long enough, it will actually start to taste sweet. By chewing for one minute, up to half of the starch may be digested before you even swallow!
See Also: Food Combining Myths
Your saliva also contains some fat digesting enzymes that help begin the process of breaking down the fats in your food. The act of chewing food—including the stimulation of your taste and smell receptors—also triggers the production of stomach acid and pancreatic juices further along the digestive tract, so that the system is primed for the whole digestive sequence.
Finally, chewing well breaks the food down into smaller pieces, so when you swallow the food, it mixes more thoroughly with stomach acid. Stomach acid starts to break down food proteins into smaller, more digestible molecules and also kills bacteria and other pathogens that may be in your food. The more surface area is exposed to stomach acid, the more effectively it can do its job.
By the way, chewing well can have beneficial effects on the other end of the digestive process as well. Thorough chewing means that less un- or partially-digested food matter enters your colon and that translates into less intestinal gas.
See also: How to Prevent Gas
How Chewing Affects Nutrition
If you’re digesting your food better, does that mean that you get more nutrition from it? Yes! Longer chewing has been shown to increase the amount of protein your body can absorb from foods and put to use building muscle. It also makes some vitamins and minerals more available for absorption—especially from uncooked fruits and vegetables. (Cooking foods has some of the same nutrient-releasing effects as thorough chewing.) Chewing also increases the amount of fat that is absorbed from foods that contain both fat and fiber, such as nuts.
Does Chewing Affect Calories?
But wait a minute. This whole chewing thing seems to be taking an unexpected turn. Does improved digestion and absorption mean that you’ll end up getting more calories from your food? Actually, it does. I’m afraid I can’t quantify exactly how many more calories you might absorb by chewing well—although I don’t think it’s enough to get too excited about.
(I can, however, tell you that you’ll burn an extra calorie for every five additional seconds you chew.)
And there’s one more thing to consider: Converting more of the starches into simple sugars by chewing foods more thoroughly can also increase the glycemic index of food. I’ve talked about glycemic index in previous articles but in a nutshell, this means that well-chewed bread or pasta would cause a higher rise in blood sugar than poorly chewed starches.
See also: What is High Glucose?
Can Chewing More Help You Lose Weight?
Studies have found that taking smaller bites and chewing them longer can decrease your food intake at a meal by as much as one-third.
Nonetheless, chewing each bite of food more times can actually help with weight loss. Chewing more means you eat a lot more slowly and this gives the hormones that signal satiation, or fullness, a chance to reach your brain before you’ve polished off the entire contents of the buffet.
Studies have found that taking smaller bites and chewing them longer can decrease your food intake at a meal by as much as one-third. Obviously, this more than compensates for a couple of extra calories that all that chewing might release. Eating smaller portions also has a much more profound impact on your blood sugar levels than the change in a food’s glycemic index as a result of the extra chewing.
See also: How to Eat Less Without Feeling Hungry
How Long Should You Chew Each Bite?
There’s no specific number of times that you must chew each bite and some foods require more than others. But with most of us chewing each bite of food just 5 to 7 times, we could probably all benefit from slowing down and chewing more thoroughly.
To sum up, chewing your food more thoroughly can improve your digestion, make your food more nutritious, and help you control your intake. It may also enhance your appreciation and enjoyment of the food—and it’ll probably keep you from talking with your mouth full, which I know Modern Manners Guy will approve of.
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How Chewing Affects GI (Q&A with Dr. Jennie Brand Miller)
Chewing Almonds Affects Satiety, Nutrient Absorption (American Journal of Clinical Nutrition)
Chewing and protein metabolism (American Journal of Clinical Nutrition)
Particle Size and Nutrient bioavailability (Journal of Agricultural and Food Chemistry)
Effect of Bite Size and Chewing Time on Satiation (American Journal of Clinical Nutrition)