Cow's milk is the most common cause of food allergies (in addition to being a common cause of food intolerances). Unlike cow's milk intolerance which is usually a reaction to the sugar lactose, allergies to cow's milk are usually from the proteins that are in the milk. Infants who have an allergy to cow's milk based formulas should usually be changed to an elemental or hydrolyzed formula, such as Nutramigen or Alimentum. Soy formulas and goat's milk may not be good alternatives in this case, although they usually are for older children, because many infants with allergies to cow's milk proteins are also allergic to the proteins in soy and goat's milk.

Other foods to avoid if your child is allergic to cow's milk include, but are not limited to, buttermilk, cheese, evaporated and condensed milk, ice cream, yogurt, instant mashed potatoes, margarine, casein, cream, hydrolysates, lactalbumin, nougat, sour cream, whey, and other foods made with milk. Older children who are unable to drink milk or eat milk based foods should be sure to have additional sources of calcium in their diet, including calcium fortified juices.

Read The Rest Its VERY interesting: Food Allergies in Children - Keep Kids Healthy

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