Can Bread Really Make You Fat?
Diet best-sellers call them "toxic" or "poison." Truth is, carbohydrates are your best weapon to control hunger and lose weight.
By Nancy Monson
Carbo-bashing is the current order of the day: Burgers are being stripped of buns, turkey is losing its stuffing, and steak is gaining ground over pasta-and-salad meals. But ditching carbs may not be the smartest diet move.
MYTH: Carbohydrates make you fat.
Carbohydrates are an essential part of a healthy diet. They’re the body’s fuel of choice: Glucose—the body’s gasoline—is more readily available from carbohydrates than protein or fat.
To lose weight: Use carbs. Yes, eat more! "People who eat complex carbohydrate–rich diets tend to be leaner than those on other diets, probably because they feel fuller after eating and are consuming fewer high-calorie, fatty foods," says registered dietitian Marsha Hudnall, nutrition director at Green Mountain at Fox Run, a weight-management community in Ludlow, VT. "Variety creates satiety," she says.
But what about the impressive weight-loss claims for protein diets? "Protein diets appear to be easy to follow, and you lose weight quickly because you’ve eliminated two whole food groups (starches and fruits). And there's only so much steak you can eat," says Johanna Burani, a registered dietitian in Mendham, NJ. "But because the diet is so restrictive, people get sick of it. And when they go off a protein diet, the body stops burning fats for energy, which can cause almost immediate weight gain. So it’s not a real fix for a weight problem."
Numerous studies have shown that eating a diet high in complex carbs can help you to lose weight—and more important, maintain the loss. Yet there are few well-performed studies documenting the health and sustained weight- loss effects of high-protein diets.
MYTH: Some carbohydrates are more
fattening than others.
TRUTH: How quickly the calories from carbohydrates are turned into glucose varies. That’s important when you’re talking about feeling satisfied after eating; the more slowly glucose is released into the blood stream, the longer you’ll keep hunger at bay.
"Researchers rank carbohydrates from 0 to 100 based on how fast they are converted to glucose and enter the bloodstream, a rating called the Glycemic Index (GI)," says Burani. The higher the GI of a carbohydrate, the faster it is broken down in the body and the more quickly and dramatically it raises your blood glucose level. Pure glucose is 100, a baked potato can be as high as 93, and nonfat, plain yogurt is 14. (See box, "Foods to Fuel You" for rankings of commonly consumed carbohydrates.)
To lose weight: Expand your definition of carbohydrate. You should get 55 to 60 percent of your total calories from carbohydrates, and we’re talking fruits and vegetables here, not just the starchy bread/rice/pasta options at the bottom of the food pyramid. Whole grains, fruits, and vegetables contain lots of fiber, so they are digested slowly, giving them a lower GI index. When you do choose bread/rice/pasta, make sure you pick fiber-rich whole grain or cracked wheat breads, brown or Basmati rice, and semolina pastas made from durum wheat.
Don’t overcook carbs: Spaghetti cooked al dente has a GI of only 41. The light cooking maintains the layers around the starch at the core of the pasta. Digestive enzymes must gnaw through these multiple layers to get to the starch. If pasta is cooked until it is very soft and loaded with water, however, these layers will degrade and the food will have a higher index (close to 100), says Richard Podell, M.D., author of The G-Index Diet. If you crave potatoes, steam them. Mashing potatoes creates more surface area for digestive enzymes to attack, increasing the GI rating.
Foods to Fuel You
Bagel (small, plain) 72
Dark rye black bread (1 slice) 76
Jelly beans (10 large) 80
Rice cakes (plain, 3 cakes) 82
Instant mashed potatoes (1/2 cup) 86
Red-skin baked potato (1 medium boiled) 93
Dates (5 dried) 103
Green grapes (1 cup) 46
Orange juice (1 cup) 46
Oatmeal (old-fashioned, cooked, 1/2 cup) 49
Special K cereal (1 cup) 54
Banana (1 medium) 55
Sweet corn (canned, drained, 1/2 cup) 55
Light microwave popcorn (2 cups popped) 55
Long-grain rice (1 cup) 56
Peanuts (roasted, salted, 1/2 cup) 14
Cherries (10 large) 22
Grapefruit (one half, raw) 25
Kidney beans (red, 1/2 cup ) 27
Skim milk (1 cup) 32
Fettucini (cooked, 1 cup) 32
Nonfat, fruit-flavored yogurt (8 oz.) 33
Apple (1 medium) 38
Pear (1 medium) 38
MYTH: Carbohydrates trigger binges and cravings.
TRUTH: There’s no scientific proof that carbohydrates cause irresistible urges for more food, says James O. Hill, Ph.D., director of the Center for Nutrition at the University of Colorado Health Science Center in Denver. Cravings aren’t well-understood, but there are both psychological and physiological reasons for them.
"The body may prompt cravings for carbohydrates because they’re the most direct route to fuel," says Hudnall.
To lose weight: If you’re experiencing cravings after eating certain carbohydrates, it may be because you’re consuming too many high-GI, fast-release foods that have little staying power. Add in some low-GI foods at every meal and you’ll feel fuller longer, suggests Burani. Eat a baked potato with beans; add greens, corn, tomatoes, and/or cabbage to rice and pasta dishes. "The mix of high- and low-GI foods will even out your blood sugar surges," she says.
MYTH: Carbs are less filling than higher-fat
To lose weight: Eat more low-GI foods and you’ll burn up to 200 more calories per day. A steady intake of low-GI carbs keeps blood sugar even and slows down the release of insulin, a hormone whose main job is to deliver the sugar into muscle cells for later use as fuel. Under normal conditions, when insulin is low in the bloodstream, the body burns more fat. In contrast, when there is a high level of insulin circulating in the blood, the body is programmed to store fat, says Burani. The higher your blood sugar rises after a meal, the more insulin will be released and the more storage of fat will subsequently occur.
Carbohydrate-rich foods also tell your brain you’re full faster than do fat-laden foods. And that leads to another advantage of eating low-GI carbohydrates, says Burani: They contain lots of fiber, which slows down the digestion process and makes you feel fuller. They also hold a lot of water—another filling factor—and you need to chew them a lot, which can be more satisfying.
MYTH: You shouldn’t eat carbohydrates in the
evening—you won’t burn them off, and you’ll get fat.
TRUTH: Frankly, your body doesn’t know what time it is. "There’s no alarm clock that goes off to signal that it’s 6:05 p.m. and every carb you eat from then on must now go to your thighs," says Berning. Carbohydrates not needed for immediate energy are stored for later use, but they only turn to fat if you eat too many calories, says Hill.
What’s more, most recent studies show that eating at night—whether it’s carbs or not—leads to no more weight gain than day eating. Again, it’s your total calorie count for the day that’s important.
To lose weight: If you tend to get hungry at night, try spreading your calories out over the course of the whole day, with an emphasis on low-GI carbohydrates that will keep your blood glucose level and naturally keep hunger at bay. "Women tend to be really good at restricting their calories during the day, but they end up so ravenous they devour everything in sight at night," Berning says. Eat small meals every four to five hours during the day to keep your blood sugar on an even keel and your energy level up. The meals should be primarily composed of carbs (55 to 60 percent), with a smattering of protein (10 to 15 percent) and fat (30 percent or less).
New, Diet-free Ways to Lose Weight
Weight Loss Aids: What works, what doesn't, and what's downright dangerous
By Nancy Monson
Loss weight fast—and naturally...Boost your metabolism...Pare inches off your waist without dieting or exercise...Cruise the weight-loss section in any drugstore or health-food shop and you'll find yourself surrounded by various products promising to burn, trap, and zap your fat. Some of these supplements will help you lose pounds; others are just a waste of money. How to tell the difference? Read on.
Liquid replacement shakes. Diet shakes don't help you change your eating habits; once you stop drinking them, you go back to your old, pre-weight-loss ways. Nutrition experts used to criticize them for this reason, but there is now solid data proving that shakes can actually make it easier to reduce and maintain weight loss. For instance, in a recent German study, those who consumed Slim-Fast shakes and bars (220 calories each) for two meals and two snacks a day, together with one sensible meal, lost an average of 16 pounds over 12 weeks. The study subjects who were on typical calorie-restricted diets lost only three pounds during the same period.
According to Judith Ashley, a nutritionist at the University of Nevada School of Medicine in Reno, meal-replacement products work because they control calorie intake and portion size—important since hidden calories and oversize meals are often to blame when diets fail.
The newest development in meal-replacement drinks is Satietrol, a pre-meal beverage. In one recent study, women who drank Satietrol while on a six-week calorie-restricted diet lost an average of nine pounds. They reported feeling full up to three and a half hours after having the drink and also ate less at the next meal. The beverage contains potato fibers and works because it activates the body's natural appetite-control protein, called cholecystokinin. This protein signals you to stop eating when you're full and slows the movement of food from the stomach, keeping you satisfied longer. The beverage, which you drink 15 minutes before eating a meal, contains 80 calories and is available at GNC stores for a little more than a dollar (rough the same price as a Slim-Fast shake).
Calcium. Several recent studies suggest that increasing your calcium intake helps you lose weight by blocking the accumulation of fat. "Calcium temporarily suppresses your parathyroid hormone, which regulates fat storage," says Purdue University nutritionist Connie Weaver. "Taking it appears to increase fat burning and discourages fat from being stored in your cells." In a study of 54 women, Weaver found that those who consumed the most calcium and ate fewer than 1,900 calories a day lost the most weight over the course of two years—without even changing their diet or exercise habits.
While the research isn't conclusive, your body needs calcium anyway, for bone health, so trying it for weight loss can't hurt. Weaver advises getting 1,000 mg daily through food and supplements. Take it throughout the day, but don't take more than 500 mg at a time (smaller doses ensure that calcium is absorbed). Keep in mind that this is one situation in which too much is not a good thing: Ingesting more than 2,500 mg of calcium a day can lead to constipation, nausea and even serious conditions such as kidney stones.
Conjugated linoleic acid. Sold through health-food stores and drugstores as a dietary supplement, CLA appears to help you zap fat. A fatty acid derived from sunflower oil and found in dairy products and red meat, CLA both blocks fat storage and prompts cells to dump the fat they're already holding, says Michael Pariza, Ph.D., director of the Food Research Institute at the University of Wisconsin, Madison, and the scientist who first discovered CLA.
Research on CLA has been promising: "Studies show that over four to 12 weeks of use, you can lose up to four pounds," says Delbert Dorscheid, an assistant professor of medicine at the University of British Columbia in Vancouver. "It also helps you gain muscle, to help trim inches off fatty areas—particularly the abdomen and upper arms—especially if you exercise." Since CLA makes you build muscle as well as lose fat, you won't necessarily see big changes on the scale, but your clothes will fit better. CLA may even help prevent weight gain, since increased muscle mass makes you a more efficient fat burner, says Pariza.
At the very least, CLA may simply make dieting a more pleasant experience: In a six-month study conducted by Pariza, obese people who took CLA while dieting didn't suffer as many weight-loss-related adverse effects, such as headache and nausea. (Pariza theorizes that this is because of CLA's effects on the immune system.) Only two brands available in the United States—Tonalin and Clarinol—have have been well tested for safety and effectiveness. A month's supply costs $30, but don't buy in bulk: Researchers say that for the time being, they only know it's safe to take CLA in doses of one gram three times a day for up to six months.
Chitosan. An ingredient in many so-called weight-loss aids, this dietary fiber, derived from shellfish, is purported to act as a fat blocker. But several studies dispute this claim: "We investigated how much fat subjects excreted before and after taking a chitosan product, says Judith S. Stern of the University of California, Davis. "We found no increase in fat excretion after they took the supplement , so it wasn't blocking fat absorption." Another study, which compared chitosan to the prescription weight -loss drug Xenical, also found that chitosan doesn't trap fat. Don't bother taking it, since there's little proof it works and it may actually be bad for you: According to some research, chitosan may inhibit the absorption of vitamins A, D, and K.
Pyruvate . This compound, found in many "fat-burning supplements" sold in health-food stores, may work in large doses. Some evidence has suggested that taking 22 to 28 grams of pyruvate a day can mildly assist in fat loss.
Nevertheless, according to Sukula, smaller doses may not work. The studies that have shown smaller amounts of pyruvate may be effective used supplements that were loaded with other compounds, including herbal diuretics. "We don't know if pyruvate was the active ingredient that caused weight loss," Sukula says. Other research has found that it may even work against your weight-loss goals: In one study at Appalachian State University in Boone, North Carolina, subjects who took pyruvate actually lost less weight than control subjects who took placebos.
Hydroxycitric acid. This vitamin C-like compound, sold as a weight-loss aid in drugstores and natural-food stores, is more hype than help. While a few studies have found that hydroxycitric acid (also known as HCA or hydroxycitrate) prevents a certain type of enzyme from converting excess body energy into fat, these studies are far from definitive, says Steven Heymsfield, M.D., of Columbia University in New York. "Some of the studies tested HCA in combination with other ingredients, so you can't tell if it was the HCA or the other compounds that produced the weight loss," he says. In a 1998 Journal of the American Medical Association study, Heymsfield found that HCA did not help people lose weight. In fact, study subjects lost the same amount of weight whether they took HCA or a placebo. Since there's very little data to prove that HCA works, skip it.
|A diet aid to avoid: ephedra|
|Can 2.5 million customers
be wrong? You betcha. Ephedra, a.k.a. ma huang, is a popular
component in diet pills and teas. The stimulant supposedly
suppresses the appetite and speeds up the metabolism, but
there's little proof that it works as well—or as safely—as claimed.
The Food and Drug Administration cautions against using ephedra,
since the adverse events associated with it include heart
palpitations, seizures, increases in blood pressure—even heart
attacks, strokes, and death.
Ephedra is often combined with other herbs and stimulants, such as caffeine and kola nut, which dramatically increases the potential for serious side effects. "People have died using ephedra products," warns exercise physiologist William Sukula. "Herbal does not mean naturally safe and effective."
Copyright Nancy Monson
All rights reserved.