Chew!

Do you chew? No, I mean, really chew? In our hectic lives, chewing is not very high up on our agenda. Lunchbreaks are short, and you might not even get paid for yours. We take our food to our desks and eat in front of the computer, or we eat with colleagues, chatting all through our lunch, so we’ll want to empty our mouth as fast as we can. We haven’t got time, we need to wolf down that lunch. But here’s why you may want to reconsider.

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Digestion is the breakdown of foods, making them available for absorption, and it starts right there, at the top of the digestive tract: the mouth. We’ve got teeth to mechanically break down food into smaller bits before moving on to the chemical breakdown further down the line. The first thing chewing does, of course, is making it easier to swallow food. The oesophagus is narrow, and poorly chewed food can hurt going down. I guess we have all learned that the hard way.

The longer you chew, the smaller the bits: Chewing increases the surface area for digestive enzymes to work on. By chewing thoroughly, you are making it much easier for your digestive system to break down your food. Once you have swallowed, any further transport of food through your digestive system is involuntary. It just happens. It happens thanks to peristalsis: From the oesophagus down to the anus, the tube that is your digestive tract has a series of ring muscles surrounding that push your food through like toothpaste through a tube. Peristalsis is like a conveyor belt, it waits for no one. If there’s still, say, meat fibre around when it reaches the colon, then it won’t get digested. It will be putrefied. Any food components that get to the colon will provide food for bacteria. Only fibre is meant to get there. We can’t digest fibre and have no use for its smallest component – cellulose – but bacteria do. Fibre is their food, and they manage to extract further vitamins from it that we benefit from, but that we wouldn’t be able to get to without our bacteria. But other food components get putrefied or fermented by the gut bacteria. They produce gas in the process, and that can give us problems and discomfort. IBS sufferers particularly are very sensitive to the distention caused by gas, and it can cause them considerable pain.

So much for the obvious benefit of chewing, but it does much, much more. First of all, there’s an enzyme called amylase in saliva. It is designed to break down carbohydrates, and you can even taste that, if you pay attention: As carbohydrates are taken apart, those carbs that aren’t fibre end up as sugar. So, as amylase gets to work, the longer you chew, the further your carbs break down and at some point you’ll notice that the bread you put in your mouth, which wasn’t sweet to begin with, now tastes sweet. This happens fairly quickly with a piece of white bread, but takes much longer with a piece of pumpernickel. Try it and time how long it takes before you taste the sugar. It’s fun!

Chewing also stimulates the production of stomach acid. "Oh, I don't need that," I hear you say, "I've got enough of that already." The thing is that most people who are taking antacids because they think they produce too much stomach acid actually have too little, not too much. Antacid medications are therefore just going to make the problem worse. For more on that, click here

The magic powers of chewing don’t even end there: As you chew, you taste. Your taste buds send messages to the brain to let it know what it is you’re eating and your brain then tells your pancreas what enzymes to produce to digest this particular food when it gets down there in a few minutes. Isn’t that amazing? “Hello, Brain to Pancreas, Brain to Pancreas: She’s eating broccoli. Get some broccoli enzymes ready, if you please?”

Amylase is just one of many different enzymes. The stomach supplies protein-digesting enzymes, the pancreas delivers more, including more amylase. Fats are emulsified by bile, pumped into the digestive tract from the gallbladder. Emulsification increases the surface area of fats, allowing fat-digesting enzymes to work on it. You’ll want your digestive enzymes to get the job done before your food reaches the colon, then all the nutrients from what you’ve been eating can get absorbed.

And one last thing on chewing: If we take the time to chew, we may actually notice when we're full and are less likely to overeat. 

  1. Sit down to eat. 
  2. Don't sit down in front of your computer. You are neither working, nor eating properly if you eat at your desk. 
  3. Don't get distracted by watching the telly while you eat. 
  4. If you're eating with colleagues, friends or family, don't forget to chew, much as you would like to chat. 
  5. Put your knife and fork down between bites. 
  6. If you were to spit out your food just before you are ready to swallow, no one should be able to identify what you've eaten. That's how long you need to chew for.