You may think you're eating less and working out lots. So why can't you lose any weight?

There's your friend in the size 6 jeans who always seems to be attacking a cookie-dough ice cream cone; there's the stick-figure colleague who lunches on burritos the size of her head. And then there's you. Day after day, you toss the bread from your turkey sandwich, nibble on a Baggie of carrots, and refuse desserts—yet you can't get the scale to budge downward. How is it that you're still heavy when you'd swear on a stack of pancakes, "But I don't eat that much!" Of course, many will acknowledge there's no mystery as to why they struggle with their weight: They eat more than they should. But a persistent minority of people recount tales of heroic food deprivation followed by a humiliating inability to lose a single pound. What's going on with them?

Here are three possible explanations:

Second-helping amnesia

Stealth Spud Syndrome

A Weight Vaccine?

• This article—and over 100 more empowering pieces—appears in the collection available at www.bigbookofhappiness.com

From the February 2007 issue of O, The Oprah Magazine

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