You apply lotion or body cream to get smooth, silky legs, but you end up breaking out in hives. What gives? Yes, you need to moisturize to maintain a proper skin care regimen, but your body is constantly changing, and the way it reacts to things can be just as dynamic. Knowing the top five allergens in moisturizers can help you avoid products that are likely to irritate your skin. As with food choices, skin moisturizing makes for good health. But like food allergies, some people can develop skin allergies to ingredients contained in moisturizers [source: Orton]. In this list, HowStuffWorks takes the guesswork out of identifying potential allergens in moisturizers, so you'll be ready to shop smartly the next time you go to restock your beauty bar.