Do you ever get a tingling, itchy, or scratchy tongue or throat after eating certain raw fruits, vegetables, nuts, or seeds? You aren't alone. In fact, there's actually a term for this: oral allergy syndrome (OAS).
OAS is caused by a cross-reactivity between foods and pollens, and people who experience OAS usually also have seasonal hay fever symptoms as well.
What happens is that the proteins in the foods look similar enough to the pollen proteins that your immune system causes an allergic reaction (or makes an existing one worse). Usually the symptoms are mild, localized, and dissipate pretty quickly — but they can cause enough discomfort to make you want to avoid that food.
The most common pollens that cause this cross-reactivity are from birch, ragweed, or grasses. Since the pollen production of these plants is seasonal, OAS symptoms can often increase or decline as the seasons change too. These are some of the most common foods that can cause OAS:
- Birch pollen: apple, almond, carrot, celery, cherry, hazelnut, kiwi, peach, pear, plum
- Grass pollen: celery, melons, oranges, peaches, tomato
- Ragweed pollen: banana, cucumber, melons, sunflower seeds, zucchini
If you experience OAS, there are two courses of action to think about. First, remove the trigger for your reactions by noticing and avoiding foods that cause discomfort. Keep a diet journal if you find that helpful for identifying problem foods. Since OAS occurs in raw foods, usually cooking the food will change the protein structure enough that your body will not react. Freezing can also work in some cases, so you may still be able to use those frozen fruits and veggies in your smoothies!
Second, it's important to know that OAS symptoms can be a sign that your immune system is overactive and needs rebalancing. Many instances of OAS can be dramatically improved or eliminated with six simple strategies:
1. Clean up your diet.
Pro-inflammatory sugars, trans-fats, and additives that are found in processed foods, baked goods, and candies will keep stimulating your immune system. You’ll do best to get those out of your diet and add back in abundant, varied whole foods.
2. Focus on colorful plant foods.
The phytonutrients in plant foods are excellent immune modulators. Quercetin, for example, is one phytonutrient found in apples, onions, parsley, capers, olive oil, grapes, cherries, and dark berries, which might be effective at toning down seasonal allergies that drive OAS. Just be sure to pick plant foods that are not your OAS triggers!
3. Drink plenty of water.
Histamine, a major driver of allergic symptoms, is increased when you're dehydrated, so be sure to stay well-hydrated with water or non-caffeinated herbal teas throughout the day.
4. Reduce stress.
Stress increases inflammation, which can prime your system to be more reactive to allergens. So it's important to find methods of stress management that work best for you.
5. Support your gut.
More than 60 percent of your immune system is in your gut. You can reduce the gut-driven load on your immune system by avoiding common immune-provoking foods such as dairy or gluten, adding a good probiotic, and eating lots of good prebiotics such as onions, leeks, Jerusalem artichokes, and asparagus.
6. Consult with an allergist.
You may want to consider immunotherapy: Allergy "shots" or under-the-tongue drops can be good options for desensitizing your immune system to pollens.
And although it’s rare, reactions can sometimes progress to other parts of the body — so if you experience OAS, it’s always best to consult with your allergist.