Despite the claims, made for years, new research has shown that eating your meals slower does not reduce the amount you eat during a meal. Eating slowly may not leave you more satisfied, curb your appetite. It may also not reduce the tendency to over-eat throughout the day by eating snacks between meals.
The 'eat slowly' advice was designed as a portion control method. The idea was that if you ate slowly, savoring every mouth-full. you would be more likely to leave food uneaten on the plate and less likely to gorge on food before your 'fullness' triggers could be activated while eating.
Like many claims about dieting, this one appears to be destined for the bin of debunked dieting myths.
This article reviews the latest findings about eating food slowly.
The study found that, although many people said that they felt more satisfied and 'full' after a long meal and were less hungry, it did not change their snacking behavior and food intake.
Have a long, delayed and staggered meal did induce higher satiety ratings, lower hunger ratings.
About two and a half hours after the start of each meal, both long and short meal trial groups were offered an array of traditional snacks such as apple cake, peanuts, chocolate-covered marshmallows and waffles.
The diners consumed about the same number of calories whether they consumed the previous meal in two and a half hours or in the short time 30 minutes.
For their study a group of 38 young men and women volunteers were asked to eat the same meal on successive days over different periods of time.
For the “non-staggered” meal the food was consumed in 30 minutes and for the “staggered” meal the food was consumed over a two hour period with breaks of 20- to 25-minute between courses.
The study also involved measurements of hormones. Blood samples were taken before, during and after the meal to measure the concentration of hormones involved in signalling appetite in the body.
The subjects were also asked also asked how 'full' or hungry they felt at various times throughout the meal.
When the subjects ate the staggered meal, their satiety ('fullness') hormones, that are thought to signal 'fullness' to the brain and curb the appetite, increased more slowly than when they ate the meal quickly.
For the quick meal, the hormone level rose more rapidly, peaked and then fell.
After eating the meal the group that ate the meal slowly rated their satiety higher and their hunger lower.
The level of another hormone that increases with hunger and is believed to stimulate appetite, were also lower for the group that ate the meal more slowly.
However these differences in hormone levels and feelings of hunger and 'fullness' did not significantly affect how much the groups ate as snacks after the meal.
The researchers said that the habits and attraction of tempting snack foods appeared to overcome the body’s internal biological cues about appetite and when to stop eating.
Earlier studies published in the British Medical Journal in 2002, showed that eating quickly and eating until full were correlated with being overweight.
A Japanese study surveyed 4140 adults and found that the fast eaters had the highest weight, body mass index, and total energy intake. However this study did not establish cause and effect and the over-weight people may simply eat faster.
A 2008 study examined the relationship between food consumption rate, feelings of satiation, and total energy intake. A group of 30 healthy women were instructed to eat meals slowly and quickly. For both tests the groups were told to eat until they felt "full".
For the slow consumption test, the women were provided with a small teaspoon and told to eat small bites, chewing each spoonful between 20 to 30 times, and returning the spoon to the table between bites.
For the fast consumption test, the women were given a large soup spoon and were told to eat as quickly as they could with no pauses between bites.
The study showed that when the food was eaten slowly, the women ate less food in terms of total calorie intake and the weight of food consumed.
This group also drank more water during the meal and reported higher levels of "fullness" and less hunger after the meal, despite eating less than when the meal was eaten quickly.
It has been suggested that stretching a meal out over a longer time period allows time for the body to signal that it is satiated and to stop overeating.
Another possible explanation is that the act of chewing each bite many times can stimulate the body to signal it is 'full'. It is also possible that the increased water intake in the slow eating group led to feeling fuller.
A study conducted in 2010 tested hormonal changes under different eating rates. A group of 17 male volunteers ate 300 ml of ice cream quickly and slowly. Blood samples were taken before they ate the ice cream and at a series of 30-minute intervals over the next three hours.
The study found that eating at a slower pace produced a stronger appetite-suppressing hormonal response.
Eating your food slower is likely to help you feel 'full' and less hungry and will help you consuming less calories.
If you eat quickly you may overshoot before your body has time to produce the signals to say 'stop eating you are full'.
Following the simple suggestions in the 2008 study—take smaller bites, chew thoroughly, and put your utensils down between bites—can help you eat more slowly, savour your food, and actually eat less while enjoying your meal more.
However beware of the habits and attraction of tempting snack foods that can overcome the body’s internal biological cues about appetite and when to stop eating.
As always it is a Matter of Discipline and Removing the Opportunity to snack.