There have been many guesses and lots of studies trying to determine just what causes food allergies. Also important to answer is why more children now have food allergies than ever before. One popular idea is the so-called “hygiene hypothesis,” that we use too many antibiotics and antibacterial soaps and have changed the ecosystem of bacteria so much that it affects our immune systems. Whether this is true or not is hard to say, but research continues and more of it is pointing to bacteria as playing a role in the development of food allergies.
Eczema and Food Allergies
To understand the current research on bacteria and food allergies, it is first important to understand the connection between allergies and eczema. Eczema is an inflammatory skin condition that results in dry, itchy, red and sometimes blistered skin. It has long been known that there is a connection between eczema and food allergies and children with eczema are at a greater risk of developing a food allergy.
Approximately 6 to 10 percent of kids have eczema, and of those, about 30 percent will develop a food allergy. Exactly why there is such a strong connection isn’t understood, but researchers believe it may be that the cracked skin of eczema causes children to absorb food allergens before they ever have contact with them through eating any of the common allergens. Experts suggest that all children with eczema should be screened for food allergies.
Staphylococcus and Food Allergies
Staphylococcus aureus, often referred to as just staph, is a type of bacterium that is sometimes found on the skin. It is usually harmless unless it penetrates the skin, like through a cut, or belongs to the strain that resists treatment with antibiotics. In a recent study conducted at the Division of Pediatric Allergy and Immunology at National Jewish Health, researchers were looking for connections between eczema and peanut allergies and found that staph bacteria may be the link.
All of the participants in the study had eczema, and the researchers found that those with staph on their skin were much more likely to be allergic to peanuts. What this means is not clear, but the researchers hope to be able to do more studies that will find out. It may be that eliminating the staph bacteria could prevent peanut allergies or even treat them.
The Hygiene Hypothesis
Another way in which bacteria may be connected to food allergies is through our individual microbiomes. This refers to the colonies of bacteria living on and in our bodies. Some experts believe that by using antibiotics and antibacterial products we have altered this microbiome too much. We rely on it to stay healthy, and by changing it we may have made children more vulnerable to food allergies.
One reason that the hygiene hypothesis is so compelling is that there is a parallel between antibiotic use and the increase in food allergies. The rise in the incidence of food allergies has mostly been seen in western, developed countries where we use more antibiotics and antibacterial products. Antibiotics have saved countless lives, but the unintended consequences could be more food allergies and other changes to our immune systems.
The role that bacteria play in food allergies, and in our health overall, is complicated. We still don’t fully understand it, but what we do know is that these microorganisms are important and we are changing them. Researchers hope that further study will uncover some important truths about bacteria and allergies that can help us treat and even prevent more food allergies from developing.