By Wing Sze Tang

Now that Atkins and the Zone are yesterday’s news, the latest weight-loss trend is blaming out-of-whack hormones for your flab. Too much leptin in your body is secretly sabotaging all your best efforts to shape up, according to books like The Fat Resistance Diet and The Rosedale Diet.

Is leptin a new buzzword in nutrition? “Yes, it is, especially for the layperson,” says Dr. Gary Miller, an associate professor of health and exercise science at Wake Forest University in Winston-Salem, North Carolina, who has been researching the role of leptin in obesity. “Even for scientists, it’s been around for only a decade or so, which is relatively new.”

Discovered in 1994, leptin is churned out by fat cells. The more fat you have, the more leptin you get. When it’s working properly, the hormone clamps down on cravings and tells your body to burn fat. This internal system seems designed to prevent you from ballooning out of control.

Unfortunately, these diets argue, our carb-laden meals unleash massive surges in leptin. After a while, the body begins to ignore it—a condition dubbed leptin resistance. So despite a growing waistline, you still lust after that double cheeseburger.

“Constant spikes in leptin levels throughout the day can cause a breakdown in communication between leptin and your cells,” explains Dr. Ron Rosedale in The Rosedale Diet. “It’s like having someone constantly yelling in your ear—eventually, you’re going to protect yourself by getting earplugs.”

Rosedale’s solution is to eat foods loaded with monounsaturated fats and omega-3 fatty acids—nuts, avocados, olive oil, and fish, for example—which restore leptin sensitivity by combating inflammation and lowering your overall leptin level. In The Fat Resistance Diet, Dr. Leo Galland also advocates these “good fats,” as well as carotenoids such as beta-carotene, lutein, and lycopene, which are found in carrots, spinach, tomatoes, and other veggies.

The big question is, do these diets work? On the plus side, Miller notes that this new wave seems surprisingly sensible. “Having a higher intake of good fats, and lowering empty calories such as refined carbohydrates and sugars—that’s consistent with new dietary guidelines. Eating more whole grains and fruits and vegetables, again that’s consistent with good health.” But while he doesn’t dismiss leptin diets outright, he’s skeptical. “There’s some evidence that what you eat does affect your leptin levels,” he admits. “[But] there haven’t been any studies to prove manipulating leptin is going to be a benefit in terms of trying to lose more weight.” And maybe we’re just making things more difficult than we need to. “People can lose weight and not know anything about their hormones.”

By Wing Sze Tang

Now that Atkins and the Zone are yesterday’s news, the latest weight-loss trend is blaming out-of-whack hormones for your flab. Too much leptin in your body is secretly sabotaging all your best efforts to shape up, according to books like The Fat Resistance Diet and The Rosedale Diet.

Is leptin a new buzzword in nutrition? “Yes, it is, especially for the layperson,” says Dr. Gary Miller, an associate professor of health and exercise science at Wake Forest University in Winston-Salem, North Carolina, who has been researching the role of leptin in obesity. “Even for scientists, it’s been around for only a decade or so, which is relatively new.”

Discovered in 1994, leptin is churned out by fat cells. The more fat you have, the more leptin you get. When it’s working properly, the hormone clamps down on cravings and tells your body to burn fat. This internal system seems designed to prevent you from ballooning out of control.

Unfortunately, these diets argue, our carb-laden meals unleash massive surges in leptin. After a while, the body begins to ignore it—a condition dubbed leptin resistance. So despite a growing waistline, you still lust after that double cheeseburger.

“Constant spikes in leptin levels throughout the day can cause a breakdown in communication between leptin and your cells,” explains Dr. Ron Rosedale in The Rosedale Diet. “It’s like having someone constantly yelling in your ear—eventually, you’re going to protect yourself by getting earplugs.”

Rosedale’s solution is to eat foods loaded with monounsaturated fats and omega-3 fatty acids—nuts, avocados, olive oil, and fish, for example—which restore leptin sensitivity by combating inflammation and lowering your overall leptin level. In The Fat Resistance Diet, Dr. Leo Galland also advocates these “good fats,” as well as carotenoids such as beta-carotene, lutein, and lycopene, which are found in carrots, spinach, tomatoes, and other veggies.

The big question is, do these diets work? On the plus side, Miller notes that this new wave seems surprisingly sensible. “Having a higher intake of good fats, and lowering empty calories such as refined carbohydrates and sugars—that’s consistent with new dietary guidelines. Eating more whole grains and fruits and vegetables, again that’s consistent with good health.” But while he doesn’t dismiss leptin diets outright, he’s skeptical. “There’s some evidence that what you eat does affect your leptin levels,” he admits. “[But] there haven’t been any studies to prove manipulating leptin is going to be a benefit in terms of trying to lose more weight.” And maybe we’re just making things more difficult than we need to. “People can lose weight and not know anything about their hormones.”