5 Theories Which May Explain The Rise In Food Allergies

Did you know that 6 million children have food allergies in the US?

1 in 13 children are affected. Given the standard classroom size, that is two children per class!

These statistics are alarming but very accurate!

So how did we get here?

The truth is, we don’t have one answer to explain this. The answer is likely multifactorial. We think that our rapid lifestyle change has contributed to this rise in food allergies over the past few decades.

Being a native of West Africa, my mother grew up in a country where roasted peanut protein is everywhere in the culture and is integrated very early on into the infant diet. So whenever my mother reads such statistics, she almost always mutters, “We never had food allergies when we were growing up.” She is exceedingly perplexed when she thinks about the fact that she has two grandchildren with severe food allergies.

As a food allergy parent, you may be interested in knowing where food allergies come from.
For me personally, I wanted to know if there was something I could have done to prevent food allergies in my children. Could I have eaten different foods? Should I have avoided specific foods during pregnancy, and the list goes on and on……..

Could I have done something to prevent this?

This is a tough question that I know every food allergy mama has asked at one point in time. There have been excellent studies to confirm that eating allergenic food during pregnancy or avoiding allergenic food does not play a role in whether your newborn child develops food allergies. Furthermore, there is substantial evidence that our diet during breastfeeding does not increase the likelihood of food allergies, and mothers are free to consume varied diets without limitations. Moms, know that we are not at fault. We have all done the best with the knowledge that was available at each point in time.

What are the current theories around the Food Allergy Epidemic?

1. Hygiene Hypothesis: “We Live Clean.”

You may already be familiar with the “hygiene hypothesis.” Over the years, this theory has had the most traction. This theory relates to the fact that “we live clean.” We protect ourselves from germs with medications, we wash our hands frequently, we have smaller families, and we live away from farms and animals. Since we live in cleaner and cleaner environments in the US, our immune systems have been under-stimulated. As a result, when our immune system is in contact with food proteins, it automatically interprets this protein as an “invader” or a “foreign protein.” Under-stimulation leads to an exaggerated immune response characterized by a release of mediators, which lends to an allergic reaction.

2. Genetics: What role do genes play?

We do not know of a specific “food allergy” gene, but we know that food allergy is likely an interplay between genes and the environment. Children who have parents with food allergies and allergic diseases are more likely to develop food allergies. However, surprisingly enough, we identify food allergies in families without any history of food allergies. Genetics alone are not responsible for this rise in food allergies.

3. Vitamin D Theory: “The Sunshine Vitamin.”

Now, we know that there is a link between Vitamin D and food allergies. There has been evidence to show that those with Vitamin D Deficiency are more prone to food allergies, Vitamin D is so essential that the body produces it. However, it cannot make adequate levels without sufficient sunlight exposure. These days, we live in the technology age, where we spend more time indoors as compared to previous generations. This likely contributes to Vitamin D Deficiency in our children and an increase in allergic disease.

4. Previous Food Allergy Recommendations

In 2000, Food Allergy recommendations were developed by well-meaning physicians. These recommendations encouraged the delay of allergic foods (milk, egg, peanuts, etc.) in our children’s diet in an effort to decrease the rise in food allergies. Unfortunately, food allergies continued to surge and nearly doubled in all countries that implemented these recommendations. We have since learned through pivotal landmark studies in 2015 (Learning Early About Peanuts study) that, in fact, EARLY introduction of allergic foods actually PREVENTS food allergies, and delaying the introduction of these foods is problematic.

5. Dual Allergen Exposure hypothesis and the Importance of Early Food

This theory suggests that exposure to food allergens through disrupted skin barriers (i.e., eczema skin) can lead to an increased risk of developing food allergies. If the body is first and repeatedly introduced to foods through the skin, as opposed to through the mouth and gastrointestinal (GI) tract, it may increase the likelihood of sensitization to that food and possible allergy. To further explain, the eczematous skin is a “broken barrier,” which can serve as a point of entry for food proteins that are around. When the skin is exposed to these proteins, the immune system becomes confused and can view the food protein as a “danger.” It subsequently will mount an immune response, which is an allergic reaction. This is especially problematic when allergic foods are not introduced early on in life. The first exposure to the body is through the skin rather than from the mouth—thus explaining why eczema is a leading risk factor for food allergies.

Take home: When food is eaten orally early in life, that act alone seems to train the immune system to protect against overreacting to the food proteins later in life.

So what does all this mean? How can I use this information?

In summary, the rise of food allergies is likely multifactorial in nature and cannot be explained by genetics alone. Our modern, industrialized environment has likely increased our susceptibility. The change in feeding guidelines in the United States in 2000 (delaying the introduction of certain foods) may also have played a role in the ongoing rise of children with food allergies.

As I reflect on my mother’s childhood days, it makes sense that food allergies during those times were dissimilar to our current times in the US. She grew up in a country where children remained outdoors for long periods of time, which allowed them the benefit of constant sunlight. In addition, the cultural diet naturally introduced peanuts and other allergic foods early in life.

So now what? What can we do to try to prevent food allergies?

We can implement the 3D’s (i.e., Dry Skin, Diet, and Dirt) as my Allergist colleague, Dr. Nadeau, refers to these prevention recommendations.

1. Dry Skin: We know that allergies that enter through the skin, especially before oral ingestion, can lead to allergic disease. It is helpful to keep our infants protected by avoiding detergents and drying soaps to keep their skin in great condition to protect against unwanted skin exposures to food. In addition, it is essential for babies with eczema to protect their skin with emollients, creams, and medications recommended by your Pediatrician and Allergists.

2. Diet Diversity: Diversification of the infant diet is of paramount importance. We know that eating a diverse diet during infancy can protect you against food allergies later in life. After the Learning Early About Peanut Study in 2015, we learned that the early introduction of peanut protein in infants 4 months-10 months helped prevent peanut allergy. Furthermore, once these foods have been introduced, we need to keep these foods in our diet multiple times a week from early infancy to early childhood.

3. Dirt: We need to be around more “dirt” to keep our immune system stimulated. This helps our immune system be stimulated and does not overreact to normal proteins, thereby leading to allergic responses.

I am so excited about our future with food allergies. This new science guides us on how we can reduce the risk of food allergies developing in babies and children. It tells us that what we do in the beginning affects our end outcome. As we implement these preventative strategies, we expect to end this food allergy epidemic and prevent future generations from developing food allergies.

Please “stay tuned” for our February Blog, where we discuss our Food Allergy Treatments offered at the Food Allergy Institute of North Texas.