Myth No. 7: Eating protein and carbs at different meals will help you lose weight. The Theory: Protein and carbohydrates require different enzymes for digestion; if you eat the two separately, you improve digestion and further weight loss.
The Reality: Your digestive tract can handle a variety of food groups at the same time. There is no proof that eating protein and carbohydrates separately aids digestion or weight loss, says nutritionist Christopher Gardner. Indeed, it’s healthier to combine protein and fiber-filled carbs than to separate them. “The pairing of protein and fiber is what fills you up the most and gives you the most energy,” says Elisa Zied, a New York City–based registered dietitian and a spokesperson for the American Dietetic Association. “An apple is good, but an apple with peanut butter is more filling.” Also, some of the best foods for you — nuts, seeds, and legumes — are made up of both protein and carbohydrates.
The Best Advice: Eat protein along with carbs, but choose with care. The best protein choices are lean meats, poultry, low-fat dairy products, and tofu, because they have little (if any) saturated fat. The best carbs are whole grains, fruits, and vegetables, which offer more health benefits than refined grains. “Those foods take longer to absorb, so there’s a slower release into the body and a more steady energy source,” says Hope Barkoukis, an assistant professor of nutrition at Case Western Reserve University, in Cleveland.
Myth No. 8: To lose weight, you need to cut calories drastically. The Theory: Eat much less; weigh much less.
The Reality: Sure, if you subsist on 1,200 calories a day, you’ll take off weight, but it won’t be for long. Consider an analysis of 31 studies of long-term diets, where the diets averaged 1,200 calories a day. The report, published last April in American Psychologist, found that within four to five years, the majority of dieters in these studies regained the weight they had lost.
“Psychologically, it’s difficult for people to adhere to strict diets over a long period because they feel deprived and hungry,” says Traci Mann, an associate professor of psychology at the University of Minnesota, in Minneapolis, and the lead author of the report. “Also, our bodies are brilliant at keeping us alive when we try to starve them.” Your body becomes more efficient at using the calories you consume, so you need fewer to survive. In addition, people who are put on a very-low-calorie diet (800 calories a day) have an increased risk of developing gallstones and digestive issues.
The Best Advice: Don’t starve yourself. “If you want to lose weight and keep it off forever, you need a modest calorie restriction that you simply continue and never stop,” says nutritionist Christopher Gardner. But what’s the right number of calories for you? Use this easy formula, a favorite of cardiologist Thomas Lee, and editor in chief of the Harvard Heart Letter.
Myth No. 9: Diet foods help you diet.
The Theory: Low-fat, low-carb, and artificially sweetened packaged foods make losing weight painless.
The Reality: Low fat and low-carb don’t always mean low-cal, and if you’re trying to lose weight, stocking up on these treats could undermine your efforts. In a series of recent studies, for instance, participants ate up to 50 percent more of foods that the researchers falsely labeled “low-fat” than they did of the same exact foods with real labels. “Consumers expect that low-fat M&M’s contain 20 percent fewer calories than their regular counterparts,” concluded the authors of the studies, Brian Wansink, Ph.D., and Pierre Chandon, Ph.D., in the Journal of Marketing Research, in November 2006. “Importantly, as a result, they expect that comparable increases in serving sizes are justified.” Some experts also believe that consuming artificial sweeteners might backfire. Two long-term studies looking at the drinking habits of thousands of people have found a correlation between drinking diet soda and being overweight.
The Best Advice: When you’re tempted by a snack food that’s labeled “light” or “low-fat,” check the nutrition information. Look at how many calories are in a serving, and then compare that number with the calories in a comparable product that’s not making a label claim. Then consider having just a small amount of the real thing. You may end up consuming fewer calories with, say, a full-fat product than you would with a low-fat version, because fat tends to be more satisfying.
Myth No. 10: Eating fat makes you fat.
The Theory: Fat has nine calories per gram, whereas carbs and protein have only four per gram, so to lose weight you have to avoid fat.
The Reality: Fat is not the enemy. Although fat-laden products can be full of calories, a modest amount of fat may help you feel full (so you eat less overall) and make healthy foods, like vegetables, taste better (so you may eat more of them). Fat also helps with the absorption of many important vitamins and phytonutrients, which are compounds in plants that are thought to promote health.
The Best Advice: Eat fat, but don’t go overboard. And think about which fats you do eat, as some are better for you than others. Choose monounsaturated and polyunsaturated fats, found in liquid oils such as canola, safflower, and olive; most nuts; and fish. These fats don’t raise blood cholesterol levels and may reduce your risk of cardiovascular disease. The fats to limit or avoid are saturated fats, found mainly in beef and dairy products, and trans fats, which are in a lot of packaged foods, fried fast foods, and margarine. These are no more caloric than the good fats, but they are less healthful, as they increase the risk of heart disease.
The Institute of Medicine, which advises the government on scientific matters, including health, recommends that when it comes to saturated fat, cholesterol, and trans fats, you eat as little as possible. If we’ve learned anything as we’ve swung from low fat to low-carb and back again, it’s this: There’s no need to eat dry salad or forgo any food you adore. Most everything in moderation will keep your weight where it belongs.