There's no sure way to prevent a food allergy, but you can prevent signs and symptoms by avoiding the food that causes them. If you know you or your child is allergic to milk, the only sure way to avoid an allergic reaction is to avoid milk products. Know what you or your child is eating and drinking. Be sure to read food labels carefully. Look for casein, a milk derivative, which can be found in some unexpected places, such as in some canned tuna or other meats. Ask questions about ingredients when ordering in restaurants.

Sources of milk products

Obvious sources of allergy-causing milk proteins are found in dairy products, including:

  • Whole milk, low-fat milk, skim milk, buttermilk
  • Butter
  • Yogurt
  • Ice cream, gelato
  • Cheese and anything that contains cheese
  • Half-and-half

Milk can be harder to identify when it's used as an ingredient in processed food products, including baked goods, processed meats and breakfast cereals. Hidden sources of milk include:

  • Whey
  • Casein
  • Ingredients spelled with the prefix "lact" — such as lactose and lactate
  • Candies, such as chocolate, nougat and caramel
  • Fat-replacement products, such as Simplesse
  • Protein powders
  • Artificial butter flavor
  • Artificial cheese flavor
  • Hydrosolate

Even if a food is labeled "milk-free" or "nondairy," it may still contain allergy-causing milk proteins — so you have to read the label carefully. When in doubt, contact the manufacturer to be sure a product doesn't contain milk ingredients.

When eating out, ask how foods have been prepared. Does your steak have melted butter on it? Was your seafood dipped in milk before being cooked?

While there's no sure way to prevent an allergic reaction to milk, reading labels, being cautious when eating out, and using hypoallergenic or milk-free products can help you or your child avoid an unpleasant or dangerous reaction.

If you're at risk of a serious allergic reaction, talk with your doctor about carrying and using emergency epinephrine (adrenaline). If you have already had a severe reaction, wear a medical alert bracelet or necklace that lets others know that you have a food allergy.

Milk alternatives for infants

Some research suggests that breast-feeding during the first four months of a baby's life instead of giving a standard cow's milk formula can help prevent milk allergy. In children who are allergic to milk, breast-feeding and use of hypoallergenic formula can prevent allergic reactions.

  • Breast-feeding is the best source of nutrition for your child. Breast-feeding for at least the first four to six months of life if possible is recommended, especially if your infant is at high risk of developing a milk allergy.
  • Hypoallergenic formulas are produced by using enzymes to break down (hydrolyze) milk proteins, such as casein or whey. Further processing can include heat and filtering. Depending on the level of processing, products are classified as either partially or extensively hydrolyzed. Or they may also be called elemental formulas. Some hypoallergenic formulas aren't milk based, but instead contain amino acids. Along with extensively hydrolyzed products, amino-acid-based formulas are the least likely to cause an allergic reaction.
  • Soy-based formulas are based on soy protein instead of milk. Soy formulas are fortified to be nutritionally complete — but, unfortunately, some children with a milk allergy also develop an allergy to soy.

Milk from other animals, such as goats or sheep, isn't a good substitute for cow's milk, as these types of milk contain proteins similar to the allergy-causing proteins in cow's milk.

If you're breast-feeding and your child has a milk allergy, cow's milk proteins passed through your breast milk may cause an allergic reaction. If this is the case, you may need to exclude all products that contain milk from your diet. Talk to your doctor if you know — or suspect — your child has a milk allergy and has allergy signs and symptoms that occur after breast-feeding.

If you or your child is on a milk-free diet, your doctor or dietitian can help you plan nutritionally balanced meals. You or your child may need to take supplements to replace calcium and nutrients found in milk, such as vitamin D and riboflavin.

Aug. 11, 2011

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