Food allergies are often mentioned in regard to asthma, but identifying specific food allergens and arriving at a dietary plan presents a challenge for the asthmatic and their families. Allergy testing can be helpful in identifying food allergens. The skin tests (or RAST tests) which may have been done can determine some potential food allergens. However, skin tests are designed to identify only one type of antibody, which is called the IgE antibody. These antibodies are the ones produced first upon exposure to an allergen, and they begin the cascade leading to an asthma attack. There is another class of antibody, however, called the IgG antibody, which is produced in a more delayed fashion, and are not identified by skin tests. A study published in 1995 in the journal Digestion found that 60% of people with food allergies demonstrate this with a delayed type reaction. Doing blood tests that measure both IgG and IgE antibodies for 96 food allergens best tests for these types of food allergies. An optional test can be done to measure sensitivity to 24 common spices.
If testing has not been performed, allergens must then be identified by applying the more cumbersome methods of elimination diets and rotation diets, which will not be detailed here, but a sample rotation diet is available from Nature’s Healthcare. In essence, an elimination diet involves the elimination of individual food items (i.e. milk) or food groups (i.e. dairy) and looking for improvement in asthma control. Eventhough this area involves difficult changes, with results not always seen immediately, food allergies should be considered when an asthma patient is having difficulty achieving control.
We have described for you the two types of responses for food allergies, delayed and immediate. The most common foods that produce a delayed allergic/asthmatic reaction would be chocolate, milk, wheat, citrus, and food coloring. The foods that most commonly produce an immediate reaction would be eggs, fish, nuts, and peanuts.
There are a number of food additives and preservatives that can trigger allergic/asthmatic reactions. Such additives would include dyes, such as the azo dyes tartrazine (known as yellow dye #5), sunset yellow dye, amaranth (red), and the non-azo dye pate blue. These dyes are felt to stimulate the release of leokotrienes resulting in bronchoconstriction. Preservatives identified as triggers of allergic/asthmatic reactions include: sodium benzoate, sulfur dioxide, sulfites, and monosodium glutamate (MSG).
One solid recommendation can be given to avoid exposure to these allergens:
AVOID OR MINIMIZE CONSUMPTION OF PREPARED OR PROCESSED FOODS
What is a prepared or processed food? That would be one prepared or processed by someone other than you, such as food from a restaurant, or food eaten from a can, a box, or other package. The key concept here is the more steps taken to prepare or process food before you get it, the more chance there is of an additive or preservative being added to it. The more involved you are in the preparation of your food, beginning with raw, fresh, whole foodstuffs, the more control you have with regards to what goes into it, or, more importantly, what does not.
AVOID OR MINIMIZE CONSUMPTION OF PREPARED OR PROCESSED FOODS
You will also find that this advice will reduce your intake of fat and refined sugars, which will reduce calories, facilitate weight control, and contribute to a lower risk of heart disease and stroke.
OMEGA 3 FATTY ACIDS:
Dietary intake of Omega 3 fatty acids has been associated with a decreased production of leukotrienes that trigger bronchoconstriction. Studies have shown improved control in asthmatics who eat fish rich in Omega 3’s on a weekly basis, as well as in patients who supplement with Omega 3-containing fish oils rich in EPA and DHA. Fish containing Omega 3 fatty acids include the cold water fishes salmon, herring, sardines, mackerel, bluefish, and albacore tuna. The improvement is not seen quickly, but is a more gradual process, as it involves the turnover in cell wall synthesis, reducing the availability of arachadonic acid, which results in less production of the inflammatory leokotrienes.
It should be noted that it can take up to one year or the Omega 3 supplementation to show any effect, due to the fact that the Omega 3 fatty acids must be incorporate into the cell wall. And, this change may not be seen at all if there is not a coincident reduction in the intake of Omega 6 fatty acids, such as those found in animal protein. This is due to the fact that the Omega 6 fatty acids compete preferentially for an enzyme required for the utilization of Omega 3 fatty acids.
A simple and affordable way to supplement Omega 3 Fatty Acids is with flaxseed oil, 1 tbsp. Per day. If a child finds it unpleasant it can be added to foods such as salads or any food where you would add an oil.
THE VEGAN DIET:
There’s good news, and there’s bad news. The good news is that a strict Vegan diet is associated with improved asthmatic control in 92% of patients studied. The bad news is that it took up to one year in the study to reach the 92% level, although 72% reported improvement after four months. The other bad news is that a Vegan diet is hard to follow for the uninitiated, and even harder to impose on a child with asthma who has his own ideas, tastes, and Madison Avenue-type preferences about nutrition. For those asthmatics who are willing to try this for improved control, and who have the commitment to the time, education, and discipline required to follow it, the guts of the Vegan Diet are as follows:
Meat, Eggs, Dairy.
Chocolate, Coffee, Tea, Sugar, Salt. (I know, sugar and salt)
Tap Water, especially if chlorinated.
Apples and Citrus Fruits.
Veggies: Lettuce, carrots, onions, beets, celery, cabbage, cauliflower, broccoli, cucumbers, radishes.
Beans: Except soy beans and green peas.
Potatoes in moderation.
Fruits: Blueberries, Strawberries, Raspberries, Plums, and Pears.
Bottled Spring Water only.
While not ordinarily part of a Vegan diet, the consumption of cold water fish is encouraged as a means of providing Omega 3 fatty acids. Such cold water fish would include: salmon which is not farm bred; mackerel; herring; sardines; bluefish; and albacore tuna; The typical tuna purchased at the grocery store is generally derived from Bonita, a lower priced tuna, but one which is not as rich in Omega 3’s as the higher priced albacore tuna.
Resources are available to provide recipes and cooking tips for a Vegan Diet.