How often do you hear this excuse for obesity: [Person] cannot lose weight, no matter how little they eat, because of their low metabolism." Well . . . bullshit. Here's a few excerpts from a NYT article titled "What We Think We Know About Metabolism May Be Wrong: A new study challenges assumptions about energy expenditure by people, including the idea that metabolism slows at middle age."

Everyone knows conventional wisdom about metabolism: People put pounds on year after year from their 20s onward because their metabolisms slow down, especially around middle age. Women have slower metabolisms than men. That’s why they have a harder time controlling their weight. Menopause only makes things worse, slowing women’s metabolisms even more. All wrong, according to a paper published Thursday in Science.

Dr. Klein said that although people gain on average more than a pound and a half a year during adulthood, they can no longer attribute it to slowing metabolisms.

When it comes to weight gain, he says, the issue is the same as it has always been: People are eating more calories than they are burning..