Agave nectar is a sweetener made from the desert plant Agave tequilana -- yes, the same one that produces those tequila shots "Biggest Loser" contestants binged on this week. Considering agave is four times sweeter than sugar and has a lower-glycemic index, does this mean it's healthy?

"RealAge" says this claim is more false than true. Agave is still a high-fructose syrup (75 percent fructose), and many health experts state too much high-fructose is simply not good for you, potentially increasing the risk of metabolic syndrome and diabetes.

When Dr. Oz raved about agave over at "The Oprah Winfrey Show," I ran out and bought a pricey little bottle. But I used it sparingly, only on oatmeal. So a big red light to piling on the agave: It's still a processed form of fructose and moderation is best. Check out this Dr. Oz webcast transcript on one of his favorite breakfasts -- steel-cut oatmeal with agave or raisins for sweetness, and a tablespoon of flaxseed oil instead of butter.