If there's one thing that you undoubtedly know about allergies, it is that they can be annoying and may interfere with your day. But beyond that, just how much do you know about seasonal, indoor, and outdoor allergies? Below are some interesting facts which may surprise you.

1. Allergies are extremely common.

According to be Asthma and Allergy Foundation of America (AAFA), there are over 50 million people in the United States alone who suffer from allergies every year. They affect around 8.2% of the adult population and about 8.4% of the child population in the country.

2. Allergies are expensive.

While many allergies can be treated at home, allergies frequently send people to the hospital. At the link above, the AAFA reports that around 200,000 annual emergency room visits result directly from food-related allergy attacks.

The medical costs of allergies add up rapidly each year, totaling more than $18 billion in the United States according to the American College of Allergy, Asthma & Immunology (ACAAI).

3. You can get allergies during wintertime.

A lot of people believe that you can only get seasonal allergies during the spring, summer and fall. While these are the most common seasons to have allergies which are plant-related, it is possible to have indoor or outdoor allergies during the winter months.

ACAAI states, "In many areas of the United States, spring allergies begin in February and last until the early summer. Tree pollination begins earliest in the year followed by grass pollination later in the spring and summer and ragweed in the late summer and fall. In tropical climates, however, grass may pollinate throughout a good portion of the year."

Technically, it is not actually spring until the equinox in late March. So your "spring" allergies in February are actually winter allergies.

4. Sometimes, your seasonal allergies may present as if they are food allergies.

If you find yourself coughing during or after eating, you might assume that you have developed a food allergy. It is possible that what you are actually experiencing is a manifestation of a seasonal allergy. This phenomenon is referred to as "cross-reactivity."

Describing it here, the American Academy of Allergy, Asthma & Immunology (AAAI) gives the example of reacting to eating apples during the time of year when birch pollen is in the air. The reason for this reaction is that the apple contains proteins comparable to the ones present in the pollen. Since your seasonal allergies are active, your body mistakes the apple for the birch pollen, and reacts accordingly.

5. Wearing contact lenses can make allergy symptoms worse.

If your eyes are irritated, red and uncomfortable during allergy season, it's possible you are contributing to the problem if you wear contact lenses. Pollen can get underneath the lenses, but has a hard time escaping again.

You have just learned some unexpected facts about allergies. Hopefully, you now have a little more insight into your own. If you need help coping, think about taking a healthy, natural supplement for sinus support.