Allergies : Fight Food Allergies with Fiber

For those who suffer from food allergies, a diet high in fiber could reduce or even prevent allergic reactions to foods such as peanuts, new research suggests.

The study, led by Australian scientists, suggests that the simple addition of oatmeal, apricots, bran, and other high-fiber foods to the diet could be essential to strengthening the part of the immune system that fights off food allergies. It also reveals how probiotics, or beneficial bacteria, in the gut work with the immune system to help protect against allergic reactions.

Study author Jian Tan and his colleagues fed a high-fiber diet to mice that exhibited a peanut allergy. The additional fiber affected the microbiomes in the mice's guts and colons, reducing their risk of allergic reactions. The gut bacteria broke down the fiber into short-chain fatty acids, which boosted the immune system's dendritic cells -- the cells responsible for controlling the body's response to allergens.

This study finds that eating a high-fiber diet changes gut bacteria to protect against food allergies. The researchers suggest that allergy treatments could use probiotics to recolonize the gut and prebiotics (healthy foodstuffs) to work together to prevent or reverse allergies.

Also essential to preventing allergies is vitamin A, which dendritic cells require. Vitamin A deficiency is unusual in adults, but less-than-ideal levels of this vitamin could promote food allergies in infants -- which may explain why the highest prevalence of food allergies occurs in infants and children. Researchers conclude that dietary fiber together with vitamin A (which is available in a variety of high-fiber fruits and veggies) plays a key role in protecting us from food allergies.