Quercetin helps strengthen the upper respiratory system and makes it more resistant to allergic triggers such as pollen and ragweed like a natural anti-histamine. Also an anti-inflammatory and anti-oxidant.
Because it is an anti-oxidant – is also said to play a role in improving vision and preventing cancer when used in conjunction with other nutrients.
Where to get it –
Apples, citrus fruits, grapes, raspberries, onions (especially yellow), black tea, green tea, red wine