Growing older is a fact of life. Milestone after milestone is reached. And through it all, the body ages as the years pass by. The obvious changes are easy to see: skin losing elasticity, hair beginning to gray. But there are less visible, internal changes as well.
In fact, changes in various body systems may cause some people to develop food intolerances and allergies as they grow older. A few theories that may explain why these changes happen include vitamin D deficiency, a decline in immune system function, and exposure to external cofactors such as alcohol or certain medications, which may cause the body to react to allergens that did not trigger an allergic response before.
Vitamin D Deficiency
Vitamin D is an essential nutrient for health. Sun exposure to the skin converts cholesterol to an intermediate form of vitamin D. This inactive form of vitamin D is converted to the bioactive form in the liver and kidneys. The bioactive form of vitamin D acts like a hormone, exerting its effects at distant sites in the body. There are vitamin D receptors located on tissues throughout the body. For example, vitamin D keeps bones strong by enhancing calcium absorption and preserves immune system functions.
However, in Western countries where most people work indoors and wear sunscreen religiously when outdoors, vitamin D insufficiency has increased to 50 percent and vitamin D deficiency occurs in up to 10 percent of the population.
Importantly, there may be an association between a vitamin D deficiency and the development of a food allergy. According to Vitamin D and Food Allergy, an article posted on the American Academy of Allergy Asthma & Immunology website, food allergies have reached epidemic levels in Western countries. The article notes, “As food allergies have increased, vitamin D levels in the population have concurrently decreased.”
In the article by medical researcher Cynthia Aranow, MD, Vitamin D and the Immune System, she describes the role vitamin D plays in regulating the various functions of the immune system. She reviews the possible role of vitamin D deficiency in autoimmune diseases, including autoimmune diseases affecting the skin. For example, a recent study led by dermatology professor Ulrich Amon, MD discussed clinical evidence linking low levels of vitamin D with various allergic responses, particularly the skin allergies atopic dermatitis and psoriasis, as well as food allergies.
Decline of the Immune System
According to Mirtha Whaley, PhD in The Aging Process, immunosenescence is a term used to describe changes in immune function in the elderly. The barriers in our bodies, such as the lining of the digestive tract that protect against pathogen or allergen invasions, breakdown over time. At the same time, immune cells don’t respond as quickly or aggressively to the invading pathogens as before.
Numerous researchers have speculated that this breakdown in the immune system and rising vulnerability to allergens may contribute to the development of food allergies. In fact, an increasing number of elderly patients are being diagnosed with food allergies. Dr. Noemi Bakos, a Professor of Dermatology, conducted a study that used blood tests to measure levels a specific marker for food allergens; levels of this marker are normally low. He found elevated levels of this marker for food allergens in 24.8 percent of the residents in a geriatric nursing home.
Cofactors are another category that may contribute to the development or increased severity of a food allergy or intolerance in adults. A cofactor is an external circumstance that contributes to the triggering of an allergic response. In the study reported in Cofactors in Allergic Reactions to Food: Physical Exercise and Alcohol are the Most Important, the cofactors associated with the occurrence of food allergies were predominantly alcohol and physical exercise. Further study is needed to shed more light on possible reasons why cofactors enhance an allergic response.
An important takeaway is that vitamin D deficiencies can occur at any time in life, so physicians are monitoring the vitamin D serum levels of all their patients. Nevertheless, more research is needed to understand how vitamin D supplementation can improve health outcomes.