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A Side of Science

‘Overeating does not make you fat,’ expert says

One of the recipes by chef Dawn Ludwig in her husband David’s book on eating well is for huevos rancheros with avocado and cheese. Jonathan Wiggs/globe staff/Globe Staff
David Ludwig is director of the New Balance Foundation Obesity Prevention Center at Boston Children’s Hospital. His new book includes recipes from his wife, chef Dawn Ludwig. Jonathan Wiggs/Globe Staff

In the movie “Groundhog Day,” meteorologist Phil Connors wakes up every morning to his alarm clock blaring the song “I Got You Babe” and finds he is reliving the same day over and over in a seemingly endless time loop.

So goes the familiar struggle with dieting, only the time loop keeps bringing us back to January and our renewed resolutions to lose weight.

Entrenched nutrition standards have encouraged low-fat, high-carb diets. Weight loss, we are told, comes down to a simple equation: calories in, calories out. Now some nutrition experts are saying this conventional wisdom, coupled with too much processed food, has made us fatter.


“We’ve developed a cultural delusion focused on calorie balance that has led us in the wrong direction,” says David Ludwig, director of the New Balance Foundation Obesity Prevention Center at Boston Children’s Hospital and professor of nutrition and pediatrics at Harvard University.

In his new book, “Always Hungry? Conquer Cravings, Retrain Your Fat Cells & Lose Weight Permanently” (which includes recipes developed with wife Dawn, a chef), Ludwig makes a radical suggestion: We’ve had cause and effect backward. “Overeating does not make you fat,” he says. “The process of getting fat makes you overeat.”

What causes the process of getting fat is largely the type of food we eat, he says. “The low-fat diet we were told to eat beginning in the 1970s, with all the processed carbohydrates that go along with it, raised insulin levels and programmed fat cells to hoard too many calories,” leaving too few for the rest of the body, says Ludwig.

Once fat cells are in this state of “calorie storage overdrive,” the arena is set for a battle between mind and metabolism that most of us are destined to lose, he says. The brain senses the energy crisis and responds by making us hungry and slowing the body’s metabolism. Eating less helps us lose weight in the short term, but it becomes a struggle of diminishing returns as the brain redoubles efforts to correct the imbalance.


Advances in nutrition science are what have shed new light on diet and obesity, says Dariush Mozaffarian, dean of the Tufts University Friedman School of Nutrition Science and Policy. “With the obesity epidemic that really took off around 30 years ago, we realized there is something much broader going on. When children 2 and 3 years old are getting obese, it’s not just a problem with willpower or genetics. There’s something in the environment that’s driving it.”

Mozaffarian says the problem with a focus on low-fat diets is twofold. It reduces consumption of healthy fats, like those in nuts, vegetable oils, and yogurt, and it gives a free pass to carbohydrates. Then we see an explosion in low-fat foods that are high in refined carbohydrates and added sugar. “That’s the major current problem with the food supply,” he says.

“This is really a time when a new way of thinking about things has emerged,” says Ludwig, “and we have enough information from research and from clinical practice to put together a new prescription.”

Ludwig recommends adding fats (nuts, olive oil, and avocados, for example), cutting back on refined carbohydrates and added sugar (bread, chips, sweets, sugary drinks, and so on), and eating protein from sources such as fish, meat, poultry, eggs, and tofu. He has devised a three-phase program that, he says, gets insulin under control, reprograms fat cells, increases metabolism, and puts an end to constant hunger.


If this current way of thinking is correct, we could just see an end to dietary “Groundhog Day.”

One of the recipes by chef Dawn Ludwig in her husband David’s book on eating well is for berries with fresh whipped cream and dark chocolate. Jonathan Wiggs/Globe Staff/Globe Staff

Valerie Ryan can be reached at