Why Diets Don't Work
Low-Fat Follies and Low-Carb Craziness
To date, there is only one proven way to lose weight: Eat fewer calories than you expend through daily activity and metabolic functions (heart beat, breathing, etc.). But neither consumers nor food manufacturers like to hear this. Consumers dislike counting calories because it is tedious and complicated; food manufacturers resist any advice that ultimately asks consumers to eat less food.
Hence the appeal of low-fat and low-carb diets. You don't have to count anything; just avoid any of the "forbidden" foods. Food manufacturers are able to tout the health benefits of products that fit the desired characteristics (e.g., marshmallows and Jell-o promoted as "Naturally Fat Free!") and create substitutes for the forbidden products—including such seemingly ridiculous products as fat-free cheese and low-carb bread.
There is even some logic to both of these schemes. Since fat has twice as many calories per gram as carbohydrates and proteins, cutting fat will lead to a reduction of overall calories—assuming that the dieter does not eat more of other foods to compensate. Because fat increases satiety, low-carb dieters tend to feel full on fewer calories. According to one study, followers of the Atkins diet averaged about 1,500 calories per day, which is a low enough level to induce weight loss in all but the elderly or very sedentary.
However, both types of diets also overlook several important factors. Neither diet takes nutrition into account; even if dieters lose weight, they may not be getting all the vitamins and minerals they need. This is particularly true of low-carb diets that restrict fruit and vegetable intake, but even low-fat dieters can get lulled into thinking that they can eat whatever they want (as long as it's low-fat or fat-free) without considering nutrition. (I was guilty of this back in college—I though I was virtuous when I made a meal out of plain bagels smeared with fat-free cream cheese or snacked on sugary canned cranberry sauce.) During the 1990s, dietitians began to call this "Snackwells Syndrome."
Both diets also tend to "throw the baby out with the bath water." It's true that saturated fats (found in animal products like whole milk, butter, and cheese) have been linked to heart disease and cancer, but monounsaturated fats (found in olives and olive oil, avocados, and nuts) may offer some protection against heart disease. Also, some fat is necessary for vitamin absorption. Similarly, refined carbohydrates like sugar and products made with white flour offer a lot of calories and little nutrition. However, fruits, vegetables, and whole grains are loaded with vitamins, fiber, and protective phytochemicals. But these nuances can be difficult to communicate—hence the appeal of a more simplistic approach such as "all fats are bad" or "cut out all carbs."
Finally, although both low-fat and low-carb dieters insist that their program is a "lifestyle change" or "way of eating," both can be hard to sustain over the long-term.
Dieting Risks and Dangers
Drugs and Supplements
Advertisements for weight-loss drugs and supplements are everywhere—in magazines, on late-night infomercials, on fliers posted to neighborhood bulletin boards, even (or perhaps especially) in e-mail. Most of these products will slim little more than your bank account. Some prescription drugs can be effective, but even these can have serious side effects. Some supplements can be deadly.
Weight-Loss Surgery
In 1999, singer Carnie Wilson had weight-loss surgery—and allowed the procedure to be broadcast over the Internet. She subsequently lost 155 pounds (and went on to pose for Playboy). Celebrity weatherman Al Roker followed suit in 2002, shedding 100 pounds. Wilson and Roker, as it turns out, were just part of a much larger trend: According to the Agency for Healthcare Research and Quality, the number of Americans undergoing weight-loss surgery more than quadrupled between 1998 and 2002.
Weight-loss surgery (also called gastric bypass surgery or bariatric surgery) usually entails using an adjustable band to reduce the size of the stomach and rerouting the lower intestine so that food bypasses the lower stomach. A normal stomach can hold about three pints of food at a time; after surgery, the patient can usually consume between half a cup and a cup of food at a time.
Bariatric surgery is frequently raised as a weight-loss option for individuals who are morbidly obese—that is, who have a body mass index (BMI) of 40 or greater. (That's 232 pounds for someone who is 5'4", or 294 pounds for someone who is 6'0".) However, it may also be considered for individuals with a BMI between 35 and 39 who also have at least one comorbidity, such as heart disease or diabetes.
Over five years, most gastric bypass patients lose at least half of their excess weight. However, the surgery is not without potential side effects. Vitamin and mineral deficiencies are most common, but other possible side effects include post-surgical infections, gallstones, hair loss, and osteoporosis. Up to 20 percent of patients need repeat surgeries to repair complications, such as abdominal hernias, and as many as 1 in 200 patients die from surgical complications.
In my experience working with online weight loss communities, I've seen a great deal of stigma directed toward patients who choose weight-loss surgery. Those who have chosen to lose weight through diet and exercise alone may be inclined to think that choosing the surgery is an "easy way out." However, even weight-loss surgery patients must learn to eat well and to exercise after surgery. In fact, one of the nastier side effects of some surgical procedures is "dumping" after a large, high-fat, or high-sugar meal—nausea, weakness, sweating, faintness, and diarrhea.
Yo-Yo Dieting
Depending on the statistics you read, up to 85 percent of individuals who lose a significant amount of weight will eventually regain it. Many dieters lose and regain weight repeatedly in a pattern known as weight cycling or "yo-yo dieting." Some studies suggest that weight cycling increases the risk of high blood pressure, gallbladder disease, and high cholesterol. Of course, weight cycling also takes a psychological toll. Indeed, some researchers believe that weight cycling is more dangerous than maintaining a stable but too-high weight.