
Onions and garlic are packed with quercetin, another secret weapon that helps fight allergies by acting like an antihistamine. Quercetin also acts like vitamin C and quells inflammation in your system, which helps stem the side effects associated with allergic inflammation, such as stuffy noses. However, quercetin isn’t absorbed very easily from food. So, although eating lots of onions and garlic may ward off some symptoms, you might consider a 400 to 500 mg supplement if you have severe fall allergies.