Read this and lose 50 pounds
Yes, and in only five minutes, in your sleep, while you’re cleaning your oven
By SUSAN IPAKTCHIAN
Wanna lose some weight? Try a daily 5,000-calorie menu consisting of three dozen eggs and 2 pounds of meat.
Or you could gulp a few teaspoons of oil every three hours and eat lots of chicken and fish at mealtimes.
Don’t like the sound of those diets? Perhaps you prefer a behavioral approach. Try a daily meditation on a bleak future in which obesity propels you inexorably toward death while health-care bills drain your bank account.
Everybody, from quacks to celebrities to your next-door neighbor, has a sure-fire method for losing weight. And they all want the blessing of nutrition expert Christopher Gardner, PhD, assistant professor of medicine at the Stanford Prevention Research Center.
After Gardner’s March 2007 report in the Journal of the American Medical Association on a yearlong comparison of the diets espoused in four popular books, dieters deluged him with e-mails seeking his opinion of their own weight-loss methods.
He cites the law of averages. “No matter how crazy a diet might be, it will work for someone if enough people try it,” says Gardner. “If you give it to 100 people, it might work for only two of them, but the people promoting the diet don’t test it that way; they simply focus on the two successful stories.”
While appreciating the sincerity of fad diet devotees, Gardner gently points out that the key to weight loss has changed little in the last 50 years: Eat balanced, nutritious meals while cutting calories, and exercise daily.
So, what makes Americans turn up their noses at the proven eat-right-and-exercise advice and instead gobble up the latest diet gimmick? Gardner offers three explanations. First, many people lack the science know-how needed to distinguish credible theories from quackery. And second, media coverage of nutrition is often confusing, hyping a food or behavior one month only to denounce it the next. Take margarine, for example. It was originally developed as a way to use up an excess supply of vegetable oil after World War II. Years later, studies showed that margarine had less saturated fat than butter, so nutrition experts hailed it as a healthy alternative to butter. But now researchers know that most margarines are high in trans fats, which boost the “bad” cholesterol levels in the blood, putting margarine in the black-hat role.
“People end up thinking, ‘These scientists can’t make up their minds, so I’m not going to believe them,’” Gardner notes, pausing to add: “But then, why would you believe Oprah?”
Which leads to the third factor: the power of personal anecdotes. If friends, relatives or influential figures like talk-show host Oprah Winfrey describe a diet that worked for them, you’re likely to believe it will work for you, too.
This all underlies a larger issue; namely, that losing weight isn’t easy. For years, physicians and health experts believed that controlling one’s weight was mainly a matter of willpower. But Gardner says an increasing number of experts now recognize that genetics and environment play crucial roles.
Gardner’s JAMA study showed how difficult losing weight can be. For the study, 311 pre-menopausal overweight women were randomly assigned to follow one of four diet books — the Atkins, Zone, LEARN or Ornish diet — representing the full spectrum from low- to high-carbohydrate intake.
After one year, Gardner found that the women on the low-carb Atkins plan lost the most weight. But even these women lost just 10.4 pounds on average — less than 1 pound a month. Additionally, few women on any plan stuck to their assigned diet, often consuming far more fats or carbohydrates than specified.
Gardner speculates that the Atkins approach might have fared better because it has a simpler message — cut your carb intake. But he notes that the study results don’t prove every single person will lose weight by following the Atkins plan.
“I love knowing where the truth is and isn’t,” says Gardner, who earned his undergraduate degree in philosophy, “and I think I’m pretty good at not overstating how much we know. And in nutrition science, there are really very few solid answers that we can give people. For example, when people eat something for a study, that means they didn’t eat something else. So then you have to figure out, was the result due to what they ate or what they didn’t eat?”
Gardner didn’t set out to be a nutrition researcher. His original goal was to open a vegetarian restaurant, so he enrolled in nutrition courses to make sure that the vegetarian approach stood the test of science. “I think it’s totally scientifically valid,” Gardner says with a smile. “I just never got back to the restaurant idea.”
After receiving his PhD from UC-Berkeley in nutrition science, he came to Stanford in 1993 for postdoctoral training. “This old Italian nutrition scientist met with me and he said, ‘Oh, I’m happy you enjoy this field, but it’s too bad because we actually already know everything. Everybody’s trying to run around and fine-tune it, but they never really change it much,’” Gardner recalls.
Fourteen years later, Gardner ponders whether the old scientist was correct. “Well, yeah, the major public-health recommendations for a healthy diet haven’t really changed,” he says. But teasing out what makes particular foods healthy or unhealthy remains a necessity. He points to omega-3 fats as a good example. Today’s health-food industry touts omega-3 fats as potential weapons against heart disease and some types of cancer. But Gardner says there is no scientific agreement on the best dose, nor on whether fish or plants are the best source of omega-3s. One of his current studies addresses this very question.
So, while Gardner and other nutrition scientists continue their effort to understand how specific foods and nutrients fit into a healthy diet, the overall message remains essentially the same. “If you want to boil it down to the fewest words, my favorite thing to say is: Eat a plant-based diet with variety and moderation,” Gardner says. “Of course, I always have to add that ‘plant-based’ doesn’t mean sugar cane, and ‘variety’ means a variety of good food choices. Don’t eat Twinkies; that’s not real food.”
And when you pass by the racks in the grocery store filled with magazine covers all promising “a new diet for the new you,” steer your cart over to the produce section instead and spend your dollars on greens — and yellows and oranges and reds. It’s your safest diet investment.
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