The terms food allergies, food sensitivities and food intolerances tend to be used interchangeably to describe reactions to particular foods. Food allergy involves the immune system and can be life-threatening. Food intolerances or sensitivities are not immune reactions, but can still cause discomfort such as gastrointestinal upset or a runny nose. Iron deficiency can be a result of food intolerances that cause poor iron absorption.
Iron is one of the important minerals in the body. It is essential for a number of proteins and enzymes, especially hemoglobin, which carries oxygen, and myoglobin, a protein that supplies oxygen to muscles. Iron assists in many biochemical reactions in the body such as regulating cell growth. If you are in good health, you can usually get enough iron from your diet. Menstruating or pregnant women and children, from infants to adolescence, are at higher risk of developing a deficiency because their iron needs are higher.
A food allergy or intolerance can cause many symptoms. According to Lawrence Wilson, M.D., a specialist in food intolerance and nutritional balancing, some of the diseases related to food intolerance or allergy include celiac disease, colitis, diabetes, hypothyroidism, multiple sclerosis and psoriasis. Behavior problems in children, anxiety, asthma, rashes, headaches and insomnia are all possible symptoms of a problem with certain foods.
Allergy and Malabsorption
Some diseases that cause malabsorption may be the result of food intolerance or allergy. Celiac disease, Crohn’s disease and colitis are malabsorption syndromes that Wilson implicates as resulting from food intolerances. These diseases can cause inflammation of the small intestine and prevent nutrients, such as iron, from being absorbed. The inflammation can also result in intestinal bleeding, which can cause anemia and further lower iron levels.
Milk and Iron Deficiency
According to pediatrician Dr. Alan Greene, excess milk consumption in young children can lead to iron deficiency because it irritates the intestine and because the calcium in the milk prevents proper iron absorption. He notes that this is not the same thing as lactose intolerance, when a child lacks the enzyme needed to digest the milk sugar, lactose. Nor is it a true allergy, because there are no symptoms involving the immune system, such as wheezing, hives or facial swelling.
The Bottom Line
It is most accurate to say that food allergies can cause iron deficiency rather than that iron deficiency affects food allergies. Iron deficiency in and of itself has no effect on food allergy or intolerance, although it can add to the symptom load by inducing fatigue or by decreasing immune system function, which increases the susceptibility to infection.