How many times have you heard or read this:  Your grandmother was right, you should chew each bite of food 32 times (or some number close to that).   Back when you first heard it, you were probably thinking she was saying it so that you wouldn’t choke on your food.  Well, that’s always a good reason to thoroughly chew.  In fact, my dad choked on a bite of food when he was young and the experience frightened him enough that he became one of the best chewers I’ve ever met.  To this day, he’s always the last one at the table to finish his meal.

But it turns out that there are lots of not only good, but great reasons to give your teeth a workout every time you eat.  Here are some of them:

• It starts the digestive process and increases the surface area of the food so that stomach acids and digestive enzymes can better access it. I’ve never known my dad to have digestive problems.  He has a ‘cast iron’ stomach, so to speak…
• It enables you to absorb more nutrients because the food is better digested
• It helps lower the risk of autoimmune disorders – poorly digested proteins (i.e., long polypeptides) are more likely to ‘react’ with the immune system andmore likely to resemble a protein present in the body.  If the immune system decides it doesn’t like the looks of the food you just ate, it’s now on alert to attack and destroy anything similar, even if it’s part of your thyroid, or pancreas, or nervous system, etc.

And if you’re trying to lose weight, here is one that you’ll be very interested in.  An eating study published in the Am J Clin Nutr (2011; 94:709-16) with obese and lean Chinese men found that the obese men ingested more food and chewed less than the lean men, although their bite sizes were similar.  No big surprise.

However, they then had both groups of men eat a 2,200 calorie meal on two different occasions.  At one sitting, they had the men chew each bite (10g of food/bite) 15 times and for the second meal, the men were instructed to chew each bite 40 times.

At thirty minute intervals following the meals, the levels of three gut hormones were measured from plasma samples:

1. Ghrelin, aka, “the hunger hormone,” is a neuropeptide that works on the hypothalamus to increase hunger and prepare the stomach for food when it is empty and it’s secretion stops when the stomach is full.
2. Glucagon-like peptide 1 (GLP-1) stimulates a decrease in blood glucose and slows rate of absorption of nutrients into blood by reducing gastric emptying.
3. Cholecystokinin (CCK) is released after a meal into circulation from small intestine and reduces food intake

The results showed that the levels of ghrelin were lower after 40 compared to 15 chews and the levels of GLP-1 and CCK were both higher after 40 versus 15 chews—in both lean and obese men.   In addition, both the lean and obese groups ate about 12% less when they chewed 40 times, compared to 15.

They chewed more, yet ate less.  It also stands to reason, then, that besides consuming less calories, they burned more calories chewing.  If you’re trying to lose weight, this seems like the perfect weight loss tip that doesn’t involve long workouts at the gym or deprivation—burn calories while you eat—giving your hormones a chance to work in your favor with increased satiety. It seems like a win-win to me.  So the next time you sit down to a meal, chew on that!