Can a Whole Food, Plant-Based Diet Help With Allergies?

By Thomas Campbell, MD
June 13, 2017

Q: Can a whole food, plant-based diet help with allergies?

A: Allergies have been increasing in prevalence in the general population over the past 20 years, and it has been a subject of great debate as to the cause of this conundrum.

My answer is not going to be terrifically satisfying, but may offer some hope. I am not aware of any compelling research to suggest that changing to a plant-based diet can effectively treat or improve environmental allergies. However, I wouldn’t rule out a role for food altogether. Let me explain:

Allergies go hand in hand with congestion of the sinuses and nasal passages. For those with chronic congestion and recurrent upper airway problems, some of their symptoms may be exacerbated by seasonal allergies. The removal of dairy from the diets of some patients has led to improvements in recurrent congestion and bronchitis, as described in a paper in the Journal of The American Medical Association in 1966[1]. Researchers write:

We have recently encountered four children whose predisposition to recurrent respiratory tract infections was relieved by the simple expedient of excluding cow’s milk and dairy products from their diets; each child had one parent with analogous if not identical symptoms, who likewise was completely cured when cow’s milk and dairy products were excluded from his or her diet. We think that this syndrome represents a relatively common problem which is not usually recognized as such.

And while it is clearly true that not all patients with congestion will respond to a dairy free diet[2], it seems like a reasonable trial for a number of reasons.

Other studies more directly address the question of diet and allergies. A recent study on mice[3] shows that a high-fiber diet created significant differences among gut bacteria, immune system cells, and allergic reactions to food compared to a low-fiber diet. Consuming lots of fiber keeps healthy bacteria in the gut happy, which in turn helps keep the lining of the gut happy and healthy, which in turn may lower the risk of allergic reactions to food. In pregnant women and their infants, taking a probiotic supplement containing potentially helpful gut bacteria (bifidobacterium) reduced the risk of eczema (a skin condition correlated with allergies)[4]. And in kids with peanut allergies, combining oral immunotherapy with a probiotic resulted in a more long-lasting control of allergies than otherwise would be expected[5].