Ever notice that supermarkets are installing more and more bakeries, rotisserie chicken grills, salad bars, and snack-food stops? Ever wonder why? It's to entice you to buy and eat, and buy and eat some more.

Smells have the power to make us purchase, especially if we're shopping on empty stomachs. When we sniff something appealing, the odor receptors in our noses send messages to our limbic systems, which control our emotions, memories, and sense of well-being. Freshly baked bread remind of you of the warmth of mom's kitchen? Well, then, you don't stand a chance.

And there you have it: Another reason to shop on a full stomach. Already we've got the lure of everything lining the shelves. Add the aroma of a batch of fresh bakery brownies, and you might as well just slap those calories on your thighs.