02/27/2012 03:57 pm ET Updated Apr 28, 2012

Can the 'Free Fruit' on the Weight Watchers Plan Satisfy a Carbohydrate Craver?

To the delight of many dieters and to the surprise of many, the Weight Watchers organization recently changed their program to allow dieters to eat as much fruit as they wish by removing "points" from this food group. The decision was recently reported the New York Times.

A Weight Watcher dieter is told to plan his/her daily food intake based on a point system. Foods are given specific number of points, and it is up to the dieters to choose among the selections so they do not exceed that number. For the most part, the more calorically dense the foods, the more points assigned to them. Some foods, however, regardless of their caloric value, have more points than others. These tend to be snack foods and to some extent, carbohydrates in general. The higher points of these foods supposedly encourage the dieter to eat lean protein and other foods that have fewer points rather than squandering two or three out of the daily allotment of 26 points on a snack. As a friend who is a Weight Watcher told me, "You learn quickly not to eat a food with too many points because it is like overspending your pay check. You may not have enough food to eat for the rest of the day."

The absence of points for fruits and vegetables was adopted as a means of shifting the dieter's food choices to some of these vitamin-rich foods, relatively low calorie foods. However there are some puzzling aspects to removing points from fruits when some of these foods have the same number of calories as foods with points. For example: Both a large banana and one serving of oatmeal have approximately the same calories. Yet according to the Weight Watchers plan, banana consumption is unlimited, whereas two or three servings of oatmeal will use up the limited number of points. The newspaper article quoted officials at Weight Watchers as being unconcerned that dieters might not lose weight if they indulge themselves in eating as much fruit as they want since most of fruit consumed will be low enough in calories to have little impact on total daily intake. But is this really true? Weight loss occurs only when calories consumed are less than calories needed, regardless of whether the calories are coming from pork rinds or watermelon rinds.

Although a conscientious dieter will be as restrained in eating fruit as cheese cubes, some dieters may find themselves reverting back to the mindless nibbling that brought them to a weight loss program in the first place. My weight loss clients often told me that they had no idea how much fruit they would consume each day, especially during the summer when the variety was vast. Two or three peaches, a cup of watermelon and handfuls of blueberries or grapes would not even be on their food intake radar because, as I was often told, "Fruit is good for you, so I never counted calories or even counted how many pieces of fruit I ate. When I felt like putting something in my mouth, I would reach for a plum (or strawberries or tangerine or apricot)."

What is even more troubling is that some dieters may resort to eating excessive amounts of fruit because they are attempting to satisfy their cravings for something sweet. In the New York Times article, Elizabeth Josefsberg, a New York area Weight Watchers meeting leader, disputes this notion. "When you finish a banana, you don't say, 'Gosh, I want another banana,'" she is quoted as saying. Ms. Josefsberg is only partially right. No one wants another banana. They really want a cookie. However, they may eat the second or third banana or the fifth peach because the cookie costs them too many points and the fruit doesn't cost them any.

Some people, dieters and non-dieters alike, experience a brain-influenced craving for something sweet or starchy, usually in the late afternoon but sometimes in the mid-evening. The need to eat carbohydrate is felt as, "... a jaw-aching need to munch on a carb snack," according to one of our early volunteers in a study carried out about 20 years ago. Our research at the MIT clinical research center uncovered the reason people we termed, "carbohydrate cravers," need to snack. Extensive studies revealed that the craving is linked to a decrease in the activity of the brain chemical, serotonin. This alteration in serotonin activity was associated with feelings of restlessness, distractibility, anger, fatigue and irritability. Our volunteers told us that they tend to feel this way every afternoon or mid-evening; they claimed that following a carbohydrate snack, their mood improved, and they become more focused and energetic.

Were they eating carbohydrates as a way of making themselves feel better? That turned out to be the case. Serotonin is made and its activity increased when an amino acid, tryptophan enters the brain. Tryptophan enters the brain after insulin is secreted, and insulin is secreted after carbohydrates are eaten. We believe that the urge to snack on carbohydrates in the late afternoon or evening comes from the need of our brains to increase serotonin synthesis.

Unhappily for the fruit consuming dieter, the sugar in fruit, fructose, is the one carbohydrate that does not promote serotonin synthesis. In other words, no matter how much fruit is eaten, the serotonin-generated cravings will remain.

As we describe in our Serotonin Power Diet book, relatively small amounts of carbohydrate are needed to start the process of increasing serotonin synthesis. The consumption of about 120-130 calories of a fat-free or very low-fat carbohydrate snack such as shredded wheat squares, rice crackers, jelly beans or breadsticks, is sufficient. Snacks that contain more than 1-3 grams of protein prevent tryptophan from entering the brain, so the carbohydrate snack works best to increase serotonin if eaten a few hours after protein has been consumed.

Serotonin may be a dieter's best friend, as not only does this neurotransmitter improve mood, it also increases satiety, i.e. the sense that enough food has been eaten. Eating a serotonin-producing snack an hour or so before a meal increases pre-meal fullness so that a small portion controlled meal does not leave the dieter yearning for more to eat. The snack may not be point-free according to the Weight Watchers plan, but it will free the dieter from his or her cravings.

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