At the dawn of the 20th century a popular dieting practice was known as Fletcherizing, in which you chewed each morsel of food 32 times, or for about a minute, before swallowing. Its primary advocate was Horace Fletcher, who proclaimed, ”Nature will castigate those who don’t masticate.” According to Fletcher, it was even necessary to chew liquids so they’d interact with saliva. While such sentiments may seem quaint, perhaps quackish, today, Fletcher had some notable followers in his day, including John D. Rockefeller. To prove that Fletcherizing could boost health, Fletcher, at age 58, was tested against college-age Yale University athletes in a number of physical tests; he bested them in all events. That no doubt left the students with something to chew on—or better yet, a bad taste in their mouths. In more recent times the vegetarian macrobiotic diet also advised the importance of chewing food 50 to 100 times before swallowing.
Old Horace may have been onto something. Perhaps the most overlooked aspect of dieting to lose bodyfat is eating speed. In a book published 37 years ago called Slim Chance in a Fat World, the authors, Richard B. Stuart and Barbara Davis, suggested that eating more slowly gives the brain time to register the food, which produces greater satiety, or appetite satisfaction. Recent studies confirm that eating more slowly fosters a lower intake of calories. What happens is that as you eat, the brain senses the food through certain gut hormones. Just distending the stomach with food is enough to promote the release of the hormones, which include cholecystokinin, glucagonlike peptide-1 and ghrelin. Secretion of the hormones signals the brain to turn off the appetite center in the hypothalamus, thus resulting in less desire to eat, which translates into fewer calories taken in. The process takes time, perhaps 20 to 30 minutes to peak. Eating meals rapidly doesn’t allow time for the hormones to fully secrete, or, more important from the perspective of appetite suppression, time for the brain to receive the gut hormone signals.
One study published last year involved 30 women who ate the same meal either rapidly or slowly. Those who ate rapidly took in more calories during the meal yet showed considerably lower levels of satiety. The other women were instructed to take small bites, put down the spoon between bites, and chew each bite 20 to 30 times in true Fletcherizing fashion. Those women not only consumed fewer calories than the fast eaters but also felt that eating the meal was more pleasant. Eating more slowly enabled the women to savor the sight, smell, taste, texture and flavor of the food, which led to greater meal satisfaction.
Another study involved 2,704 men and 761 women. Those who ate fast had higher rates of insulin resistance. Eating faster tends to promote a greater release of insulin, which can be excessive and which is strongly associated with the development of insulin resistance. On a more basic level, more insulin tends to translate into more bodyfat synthesis, particularly if you take in too many calories during the meal. Eating too fast almost always results in an excessive intake of calories.
Another study featured 1,122 men and 2,165 women, aged 30 to 69, whose eating habits were studied for three years. Half the men and half the women reported eating until they were full. Just under half the men and 36 percent of the women said they ate too quickly. Those who said that they ate until full and too quickly all had more bodyfat and energy intake than those who reported eating more slowly. In addition, the authors found that those who ate until full at a rapid pace were three-times more likely to be overweight than those who ate at a slower pace until full. The authors concluded that the combination of eating until full and eating quickly had a “supra-additive effect on overweight.”
The above study involved Japanese subjects who live on the island of Okinawa, which boasts some of the longest-lived people in the world. Those who survive over the century mark don’t show any signs of obesity. They follow the long-held dictum to eat 80 percent of what’s on the plate and leave 20 percent. They wind up eating far fewer total calories than other Japanese. Many scientists suggest that the lower calorie intake of the Okinawans accounts for their longevity. They also tend to eat slowly, which may underlie their ability to be satisfied with less food.
So it turns out that old Horace Fletcher may have been on the right track after all in his admonitions to slow down and chew your food thoroughly. On the other hand, he advocated a low-protein diet for increased health, thus proving that you can be right about some things and woefully wrong about others.