Friday, May 1, 2009

Why That Big Meal You Just Ate Made You Hungry

Why That Big Meal You Just Ate Made You Hungry
· By MELINDA BECK

Every few months, a new study purports to prove that a calorie is a calorie is a calorie, and that the only way to lose weight is to burn more than you take in.

But veteran dieters know something that some researchers apparently don’t: Certain foods seem to fuel the appetite like pouring gasoline on a fire. Some people find that once they start eating bread, cookies, chocolate, potato chips — or leftover Easter candy — they lose all sense of fullness and find it difficult to stop.

That’s the concept behind “The Skinny,” a new book by Louis J. Aronne, longtime director of the Comprehensive Weight Loss Program at New York Presbyterian Hospital/Weill Cornell Medical Center. He makes the best case yet why what you eat and when you eat it can make a big difference in appetite, satiety and how much willpower it takes to cut down. “It’s true that a calorie is a calorie,” Dr. Aronne says. “But what that doesn’t take into account is how some calories affect what people eat later on.”

Appetite Stokers

Some foods make it harder to stop eating:

· Bread

· Sweets

· Juice

· Pasta

· Wine or beer before dinner

· Artificial sweeteners

*Source: ”The Skinny” by Louis J. Aronne

After 23 years of treating patients — some of it espousing liquid diets – Dr. Aronne has concluded that refined carbohydrates and foods with high sugar and fat content promote what he calls “fullness resistance.” They interfere with the complex hormonal messages the body usually sends to the brain to signal that it’s time to stop eating. People feel hungrier instead.

This happens in part because refined carbohydrates raise blood-sugar levels, setting up an insulin surge that drives blood sugar down again, causing rebound hunger. That insulin spike also interferes with leptin, the hormone secreted by fat cells that should tell the body to stop eating. Obese people have loads of leptin, but it either doesn’t get to the brain, or the brain becomes resistant to it. “This is not a failure of willpower, it’s a physical mechanism,” Dr. Aronne writes. The body also becomes resistant to insulin, setting the stage for diabetes.

Other researchers have described similar phenomena. An article in this month’s Medical Hypothesis argues that for some people, refined foods with high sugar and carbohydrate content can be just as addictive as tobacco and alcohol.

Eating foods high in protein, vegetables, fiber and water have the opposite effect, Dr. Aronne says. His plan recommends revising what you eat, one meal at a time, to restore your sense of fullness:

Breakfast: Loading up on lean protein — ideally from egg whites or a protein shake — in the morning reduces hunger all day long. Eating muffins, bread, sweetened cereal and juice does the opposite. A study of 30 overweight women at Saint Louis University School of Medicine found that those who ate eggs for breakfast consumed 140 fewer calories at lunch, and ate less for the next 36 hours, compared with women who ate bagels in the morning.

Some people argue that they aren’t hungry in the morning, but Dr. Aronne notes that ghrelin, the hormone that typically signals hunger, adjusts to habitual meal patterns. After a few days of eating breakfast, you should find that you are hungry in the morning, and are eating less the night before, he writes.

Lunch: Some dieters try to cut calories by skipping this meal. But going more than five hours without food causes hunger hormones to rise and fullness hormones to drop, and sends more of the calories consumed at dinner straight to fat cells. Dr. Aronne recommends starting lunch with a salad — at least two cups of lettuce — then more vegetables, and then lean protein. Skip the cheese, croutons, bacon and creamy dressings, he advises. Using vinegar alone will cut your appetite and slow the rise in blood sugar.

Dinner: The end of the day is fraught with temptation. Obese people consume significantly more calories at dinner than slimmer people. Here, too, load up first on salads, clear soups, or high-protein appetizers like shrimp cocktail, then have a lean protein main course. Unlike some other diet plans, Dr. Aronne’s program allows a half-cup of grains or a small dessert at the end of the meal, but only if you’re still hungry.

Eating bread before dinner makes people lose their sense of fullness and eat more, Dr. Aronne warns. Alcohol makes it worse by lowering your resistance and promoting fat storage.

Snacks: Like many other weight-loss experts, Dr. Aronne believes that midmorning and midafternoon snacks can act as mini appetite suppressants, preventing blood sugar from dropping too low. But the same principles apply: high-sugar, high-starch, high-fat snacks — including those little 100-calorie cookie packs — start a vicious cycle of more cravings, whereas fruit, nuts, vegetables and clear soups can halt them.

Beverages: It should go without saying that juice and sweet soda can add hundreds of extra calories a day. A few studies have shown that even artificially sweetened beverages can prompt people to crave real sweets during the day. Cut back on all sources of liquid calories, Dr. Aronne advises; stick with water.

To be sure, if you eat as Dr. Aronne suggests, you’ll consume fewer calories overall. The point is, eating protein early in the day may make it much easier to cut down. “It definitely does make a difference,” says Ned Sadaka, a New York investment manager who consulted Dr. Aronne to drop 30 pounds that had crept up on him in recent years. He’s lost 21 pounds and 5 inches off his waist since January.

Not everyone agrees that consuming more protein cuts appetite. Harvard School of Public Health’s Frank Sacks led a study recently published in the New England Journal of Medicine that compared 811 overweight adults on four diets with varying levels of protein, fat and carbohydrate. “We found absolutely no difference in their satiety and hunger levels,” Dr. Sacks says. All the groups lost similar amounts of weight.

Other weight-loss experts say that’s not surprising, since there were only modest differences in their fat, protein and carbohydrate intakes, and many participants didn’t stick to their plans.

Eric Westman, director of the Lifestyle Medical Clinic at Duke University Medical Center , who espouses the same kind of low-carb plan that Robert Atkins made famous, says in his experience, “There is almost complete appetite suppression when you eat protein.”

The debate will doubtless continue — weight loss is an extremely complex area, and not everyone’s metabolism is the same. Dr. Aronne suggests trying his plan yourself: “Have 200 calories of egg white omelet or protein shake for breakfast, and then another day have 200 calories of juice and look at your hunger, hour after hour.” 

Sometimes being a clinical trial of one is the best way to do your own research.