For many years now, our western lifestyle has had us eating more processed food and fast food that doesn't really require much chewing. More of us are eating at our desks or on the run and generally not paying too much attention to what or how we're eating. Increasingly the result is bigger waistlines, fatigue, and indigestion.
Chewing and Weight Loss
Thorough (or mindful) chewing is the easiest way to slow down at a meal and achieve satiety or a feeling of fullness on less food. When we chew, we mechanically break food down into smaller pieces (the bolus). This makes it easier for food to travel through the esophagus to the stomach. When the bolus reaches the stomach, the stomach wall starts to expand. This expansion causes signals to be sent to the brain, telling us that we are starting to feel full. There can be a 20 – 30 minute delay between the time that we ingest food until feelings of satiety are activated. When we eat quickly, we are more likely to overeat before we get this feeling of being full. Then we get the uncomfortable feeling of being overfull. So, chewing food more thoroughly slows the amount of food entering the stomach. This results in feeling full with less food eaten. It introduces an automatic delay factor - less food in and more chance of weight loss.
Chewing and Energy
To understand the link between chewing and energy, we need to review a bit of digestion physiology.
A number of activities occur when we take the time to chew food thoroughly:
- we have more time to smell and savor our food. The smell and sight of food activates a series of signals from the brain to the cells in the stomach lining encouraging secretion of stomach acid. This stomach acid (hydrochloric acid) is essential to the continuing breakdown of food into a form that allows absorption of nutrients into our cells.
- enzymes are released by the salivary glands in the mouth which start to chemically break down food (specifically carbohydrates) while still in the mouth. Generating saliva also activates the secretion of hydrochloric acid in the stomach.
- both the mechanical and chemical breakdown of food increases the surface area of the food bolus, making further digestion and absorption of nutrients more efficient.
The longer that the food stays in the mouth undergoing both this mechanical and chemical dissolve, the easier digestion is on the rest of the body. When digestion requires less energy to transform our food to the smaller particles that we can absorb, there is more energy to be used elsewhere in the body.
How much Chewing is Enough?
That depends on both the texture of the food and how calorie-dense it is. Dry or crunchy food may take longer to chew. A calorie-dense food (and this includes yogurt and smoothies) should be chewed more thoroughly in order to add that delay so you're not tempted to overeat.
Chewing your food slowly and more thoroughly is the easiest way to improve the health and function of your digestive system and, consequently, your overall health. By freeing up the energy in the digestive system, it's available to be used elsewhere in the body.