Can Food Help your Seasonal Allergies?

Seasonal allergies can be difficult to manage ever year. Check out this post to learn about how some compounds in your food may help.

Short answer, maybe a little? But for the full answer of whether the food you eat affects seasonal allergies, first we need to talk about how the immune system works, and ways that certain nutrients can affect the immune system’s function.

IMMUNOLOGY CRASH COURSE

So some of the important players in the immune system are B cells which make antibodies. Antibodies mark molecules for destruction. They also attract another type of cell called macrophages to eat the invader. Another important cell is called an eosinophil which contains histamine. This is the molecule responsible for itching and the reason may people take anti-histamines. The last type of cell to talk about are called T cells which help regulate the type of immune response that the body mounts. The two major types are called Th1 and Th2 responses.

A Th1 response is made to bacteria and viruses typically, but when the immune system gets out of hand, this response is responsible for autoimmunity. A Th2 response is made to worms, but when the immune system goes haywire, we get allergies. So, why do we care? Because both responses cannot exist at the same time! They are on a seesaw where when one response is high, the other is low. Another T cell response called a Treg (for regulatory T cells) response can calm both sides and bring the seesaw into balance.

So if someone is suffering from bad seasonal allergies, then their Th2 response is in overdrive. One way to calm the allergies down could be to drive a Th1 response or promote a Treg response to calm both sides. So, let’s talk about how some of the nutrients in our foods can support our immune system.

Nutrients that Affect the Immune System

VITAMIN A

Vitamin A plays an important role in immune function and specifically with regulatory T cells. The presence of vitamin A can cause more Treg cells to be produced. But if levels of vitamin A are too high (like from excessive supplementation) then vitamin A can drive a Th2 allergy response. Good news is that most people get their vitamin A from vegetables in the form of beta-carotene! This water soluble form only gets converted to active vitamin A as needed and the rest is excreted. Good sources of vitamin A include liver, red/ orange veggies, some fruits like mangoes and leafy greens like spinach.

VITAMIN D

Vitamin D also supports the production of regulatory T cells. The problem is that it’s very difficult to get the recommended daily allowance of vitamin D from food alone. Vitamin D is found in fish, eggs, and possibly mushrooms if they were exposed to UV light. Humans can also make vitamin D in out skin when exposed to UV light. So, if you spend time in the sun, then you make some vitamin D, however, it’s much more important to protect your skin from sunburn and skin cancer. This is one of the few cases where supplementation is usually the best option. Vitamin A and Vitamin D work together to keep the immune system in balance.

DHA (OMEGA-3 FATTY ACID)

One omega-3 fatty acid is DHA which modulates the effects of Tregs in the immune system. DHA may help convert other T cells into Tregs, and it’s is found in fish oil supplements and fatty fish. If you eat a strictly vegan diet, you can find omega-3 supplements that are algae based.

QUERCETIN

Quercetin is a flavanoid that acts as an antioxidant in the body. Qercetin has the ability to balance the T cell response and suppress the formation of IgE antibodies (the ones linked to allergies).Quercetin is found in onions, apples, bell peppers, and berries to name a few, and it’s sometimes called natures anti-histamine.

PROBIOTICS

Probiotics affect the immune system in a variety of ways and many of the benefits can be strain specific. Different strains can drive different immune reactions, but probiotics may help maintain tolerance and keep the immune system from reacting to everything it comes in contact with. Certain strains like Lactobacillus reuteri and Lactobacillus casei may help promote Regualtory T cell production. The best way to get probiotics into your diet is to eat fermented foods like yogurt, kombucha, and sauerkraut.

Will peppers and onions cure seasonal allergies?

Nope, but long story short, it’s possible that some of the nutrients in foods we eat may support our immune system and promote different immune responses. The good news is all these nutrients have benefits beyond helping with seasonal allergies! So load up on onions, spinach, and yogurt whether the pollen’s gotten to you or not. But, I’m still going to be taking an anti-histamine everyday because I want my food to work with my medicine, not replace it!

Want another science lesson? Check out this post on vitamin deficiencies and pellagra here.

References:

1. Issazadeh-Navikas S, Teimer R, Bockermann R. Influence of dietary components on regulatory T cells. Mol Med. 2012;18(1):95-110. doi:10.2119/molmed.2011.00311.
2. Mlcek J, Jurikova T, Skrovankova S, Sochor J. Quercetin and Its Anti-Allergic Immune Response. Molecules. 2016;21(5). doi:10.3390/molecules21050623.