This article, by Dr Irene Berman-Levine, is adapted from one of her recent Newsletters. This weekly free newsletter, Dr. Irene's Nutrition Tidbits, helps you understand the confusing world of nutrition and motivates you to choose healthy foods. You can sign up for the newsletter by clicking here .
Dr Irene has also packaged many of her newsletter articles into a book, which you can order for US$16 by clicking here . Robert Griffith, Editor.

My 20 Minute Experience

What happens to you when you get really hungry? Do you overeat? Get irritable? I do both and can't wait until the food "hits", meaning it's not only in my mouth but my body feels like it has eaten, too.

This relates to a question I received recently. A reader asked, "How long does it take to feel full after eating? I heard it's 20 minutes and that is why people tend to overeat".

My reply to her was that she was correct. It takes 20 minutes for most people to feel full after starting to eating. People who eat too fast can inhale far more calories than they need in that period of time!

On Thursday I had a chance to take the answer one step further and actually do an experiment. It was 1:44 pm and I was absolutely famished. Normally I try not to let myself get this hungry but after finishing counseling clients, starting the list of business errands seemed more pressing than lunch. Lunch was actually sitting beside me in the car (a wonderful but messy vegetarian burrito) but I was determined not to stoop so low as to gobble it down while driving. That's not only a surefire way to lose eating satisfaction but I knew my skirt would suffer.

I decided the minute I got home, I would look at the clock and see how long it took to reach a "feeling of satiety". Satiety is a noun that means "the state of being full or gratified to or beyond the point of satisfaction". According to the dictionary it is derived from the Latin word satis, which means enough. In other words, I was now going to time how long it took me to go from a state of hunger to feeling like I had enough.

That's how I knew it was 1:44. After frantically grabbing a plate and a drink, I looked at the clock before starting to stuff the burrito in my mouth. By 1:48 (only 4 minutes later) I'd eaten half the burrito! I was still feeling starved but I knew, judging by the large size of the burrito, that I had already had plenty of calories for lunch. I decided to try and stop myself from eating the rest until the 20 minutes passed.

I was miserable, circling the plate, salivating, and wanting to inhale the rest of the burrito. Fortunately the phone rang at 1:53. A friend was calling to finish meal arrangements for someone who had a death in the family. I'm sure she thinks I'm crazy because she first had to hear me rant about how I was trying to hold myself back from a burrito that was calling me. Five minutes went by. I noticed I felt more in control. I could look at the burrito without grabbing it and was able to concentrate on the telephone planning.

Once off the phone I almost forgot to look at the clock. It was 2:02! I could finally eat the burrito. But I didn't. My burrito department was full! I had proved the theory that it takes approximately 20 minutes to feel satiety. Of course my dessert department was still open but that urge isn't as responsive to actual hunger . . . . sweet/fat combinations often appeal, even when hunger isn't involved. I chose an apple to try to satisfy the urge for sweet. That choice is safer than true desserts for most people watching their waist. The apple leaves a fresh taste in your mouth and is less likely to create the urge to overeat.

When is Enough, Enough?

How much damage can you do in 20 minutes of eating? Fast eaters are at the greatest risk for the most damage. A fast eater can eat three to four times the calories they need before their body has a chance to tell them they've had enough. That's why so many people get up from restaurant meals and then groan that they ate too much.

How can we slow ourselves down? The first step is to learn to savor each bite. This includes thinking about the taste and taking the time to chew before swallowing.

If you struggle with weight problems, do the opposite of what your mother always said. Spoil your appetite. If you're starving, have an 80 calorie snack 20 minutes before you plan to eat. Examples are a small piece of fruit, ½ cup of raw baby carrots or 8 oz. skim milk.

Time your family and determine if they take at least 20 minutes to eat their meal. If not, they are eating too fast. Ask if they truly taste and chew their food. The answer is probably no. Then ask them to try a meal where they concentrate on tasting each bite. Game rules could include that, to begin with, each person can only take one bite of food and then has to describe how it tastes before the rest of the group can continue to eat. Each bite must be chewed at least 10 times; forks must be put down between bites.

The Satiety Index

Certain types of foods may provide more satiety than others. One researcher, Dr. Susanne Holt, has even developed a Satiety Index.¹ I'll share with you the basics of her research but don't misuse the figures by assuming the list applies to everyone. Foods that one person may find satisfying may not work for another.

Dr. Holt created the Satiety Index by feeding small groups of 11-13 healthy fasting volunteers with foods from 1 of 6 food categories (38 different foods) in portions which provided about 240 calories. The 6 food categories were carbohydrate-rich foods (bread, rice, pasta), breakfast cereals, fruits, snacks/confectionaries, protein-rich foods, and bakery products. After eating them the volunteers were left for two hours to nibble from other foods. Their food choices were observed and every 15 minutes. They were then questioned about their hunger to see if their subjective impression of satisfaction matched their eating behavior. Finger-prick blood samples for glucose and insulin were also taken.

Each food was rated according to how much other food was eaten later. White bread was taken as the bench-mark and given a value of 100. Foods which staved off hunger pangs longer than the same calories in white bread were given scores above 100, and those which gave less satisfaction were rated below 100.

Among the 38 test foods, there were no significant relationships between satiety and plasma glucose or insulin responses. In general it was found that protein foods and high fiber, carbohydrate-rich foods are more satiating than carbohydrate/fat combinations foods. Higher fiber foods were more satisfying than their equivalent low-fiber form (i.e. whole grain pasta versus white pasta).

The higher the score, the more satisfying the food. Example scores are given below. Don't assume these results will pertain to you. This is just one small but interesting study.

Cake 65%	Eggs 150%
Doughnut 68%	Popcorn 154%
Candy bar 70%	Beef 176%
Ice cream 96%	Whole grain pasta 188%
Cornflakes 118%	Apples 197%
All-bran 151%	Oranges 202%
Whole grain bread 157%	Oatmeal 209%
White pasta 119%	Fish 225%

To lose weight, avoid the lowest numbers. For more details, see the first link below. And good luck with your slow-eating trials!