As someone who develops new food products, I've been a professional taster for 16 years. I love my job, but I'm constantly frustrated by the unwillingness of most Americans to try foods that challenge their palates.

The tongue is a unique muscle. The best way to exercise it, if you want to make the most difference to your waistline, is not to flex or fatigue it, but to stretch it. Expanding our repertoire of foods isn't just about exploration and new pleasures. It's also the first step toward eating a broader, healthier diet.

We are born loving sweetness, so we heap sugar into our lattes and drown our Chinese food in sweet sauces. But constantly indulging our craving for sweetness has an insidious effect. With each new overly sweet food that we consume, whether it is high in calories or not, we dull our palates to other tastes and flavors, especially those of nutritious fruits and vegetables.

We also may be altering our brain chemistry by eating more and more sweeter and sweeter foods. New research shows that the excessiveconsumption of calorically dense foods changes the way that our brain responds to future foods. The effect is akin to a drug addict's need for more and more heroin to satisfy his craving.

Experts in food neophobia