Featured Image for Food Allergy Basics - Part 2: The Usual Suspects - Cow's Milk

Part One of this series, Food Allergy Basics – Part 1: What You Need to Know introduces you to food allergies by explaining how the medical community identifies and separates a true food allergy from other reactions. True food allergies are marked by the response of a specific antibody, known as Immunoglobulin E (IgE), to specific food proteins. What can be accurately inferred from this is that if a food contains protein, a person can have an IgE-mediated allergic reaction to that food.

According to the Food and Drug Administration (FDA), there are currently more than 160 identified foods which cause IgE-mediated allergic reactions. Commonly referred to as The Big Eight, or in this case The Usual Suspects, peanuts, tree nuts, milk, eggs, wheat, soy, fish,  and shellfish account for 90 percent of all allergic food reactions.

Part two of this series is broken down into eight installments to provide an adequate profile for each of the eight major food allergens for which the FDA requires labeling. The first installment of Food Allergy Basics – Part Two: The Usual Suspects has already covered peanut and tree nut allergies. This installment will examine cow’s milk allergy.

Cow’s Milk

Allergy to cow’s milk is the most prevalent food allergy for infants and young children. According to Food Allergy Research & Education (FARE), 2.5 percent of children three years old and younger are allergic to cow’s milk, while only 0.2 to 0.4 percent of the general population suffers from the same allergy. FARE reports that, though the allergy typically resolves itself in childhood, milk allergies seem to be lasting longer than they have in previous decades, with children still suffering from the allergy beyond age five. The American College of Allergy, Asthma & Immunology (ACAAI) cites a study in which less than 20 percent of the observed children had outgrown their cow’s milk allergy by age four. The general consensus, however, is that approximately 80 percent of children with a cow’s milk allergy will outgrow the allergy by age 16.

Cow’s milk allergy is less often associated with anaphylaxis than peanut and tree nut allergies are; however anaphylaxis is still a concern and those afflicted with the allergy are encouraged to carry an epinephrine auto-injector as a precaution.

Allergy vs. Intolerance

Though easily confused, an allergy to cow’s milk is very different from being lactose intolerant. When a person is allergic to cow’s milk, one of the various proteins inherent in the milk or milk product triggers a reaction from the immune system, the part of the human body employed to fight foreign invaders such as bacteria and viruses. This can cause a number of symptoms ranging from severe, such as trouble breathing, loss of consciousness, anaphylaxis or even death, to relatively mild digestive issues like nausea, cramps, bloating and diarrhea.

Similar digestive symptoms are experienced by people suffering from lactose intolerance. Lactose intolerance is not an immune reaction, however. It occurs when a person lacks the enzyme lactase, which is necessary for breaking down lactose, a sugar found in dairy products.  Only a doctor can determine if you are suffering from milk intolerance or an allergy; it is important to consult with your physician before assuming you have one or the other. While unpleasant, lactose intolerance is not life-threatening.

What to Avoid

In 2006, the FDA required that foods that contain milk must be plainly labeled as such, declaring that the food “contains milk.” However, there are foods that are not covered by this law and, in any case, milk-associated products go by many names.

This is where details matter.  There are many, many products that contain milk or milk protein isolates of one sort another.  The list below is pretty comprehensive and should usually keep you out of trouble. But, new products are being developed all the time, so it pays to stay alert and up-to-date.

If you have, or suspect you have a milk allergy, there are some foods or food ingredients that should be avoided:

  • General rule: Anything with the word “milk” in it. Exception: almond milk, soy milk, etc. But read the label to be sure that actual milk or milk product has not been used in the product.
  • General rule: Anything with the word “butter” in it. Exception: nut butters and soy butters, but again, read the label to be sure.
  • Butter, butter fat, butter oil, butter acid, butter ester(s), artificial butter and artificial butter flavor, whipped butter and butter solids
  • Buttermilk
  • Casein, casein hydrolysate, rennet casein, and all forms of caseinates
  • Cheeses, all kinds, including imitation cheese and “cheese flavor”
  • Cream, including heavy cream and whipping cream
  • Curds
  • Custard and pudding
  • Diacetyl
  • Ghee (clarified butter)
  • Half-and-half
  • Ice cream
  • Lactalbumin and lactalbumin phosphate
  • Lactoferrin
  • Lactose
  • Lactulose
  • Milk in all forms, including condensed, dry, evaporated, low fat, malted, nonfat, powdered, protein, skimmed and whole, to name a few.
  • Milk protein hydrolysate
  • Nisin (an antibacterial made from Lactococcus lactis that is added to dairy products to extend shelf life)
  • Sour cream and sour cream solids
  • Sour milk solids
  • Tagatose
  • Whey in all forms
  • Whey protein hydrolysate
  • Yogurt

People with milk allergies should also be cautious with baked goods, chocolate, some candies including nougat, artificial butter flavor, margarine, kosher dairy, kosher pareve, and bacterial cultures such as lactic acid starter used in the fermentation of certain meats. These products sometimes contain milk or milk proteins.

Other Exposure Risks

There are also some unexpected sources of milk which consumers should be aware of. Casein, a milk protein fraction, is used as a filler and binder in some brands of tuna and some meat products. It has also been known to show up in fast food and non-dairy products. Milk casein can also be found in some toothpaste products, where it is used to facilitate remineralization of the tooth. Some medications also contain milk proteins.

Shellfish can contain milk, as it is sometimes dipped in milk to reduce the fishy odor. Deli meats often share slicing equipment with cheese products, resulting in cross-contact which could trigger an allergic reaction. Some products made with milk substitutes also risk cross-contact, as they are manufactured on equipment shared with milk products.

Cow vs. Goat and Sheep Milk

Some studies indicate that people with a cow milk allergy may also be allergic to goat or sheep milk. In a study reported in Allergy, European Journal of Allergy and Clinical Immunology, people with a cow’s milk allergy were found to be sensitized to whey proteins and/or the casein fraction in milk, which are also found in goat and sheep milk. Subjects did experience allergic reactions.  Conversely, people who are specifically allergic to goat and sheep milk are rarely allergic to cow’s milk.

What we Recommend

If you’re not sure whether you have a milk allergy or are just lactose intolerant, see a doctor to resolve the issue.  Mild allergic reactions can turn severe without warning.

Stick with food brands that have not caused you problems in the past, but be aware that manufacturers frequently change their recipes for their foods.

Always read labels and if necessary, inquire about the ingredients in your food, especially in restaurant settings. Experience tells us that chefs know more than the servers about exactly what’s in the food, so try to get an answer straight from the kitchen.