NEW YORK (TheStreet) -- After a brutal winter, the last thing Americans need is another headache to handle with spring still two weeks away.
But a headache may be exactly what they get -- literally -- with allergy season also coming into full bloom.
Yes, it seems fairly downbeat to associate spring with health maladies, particularly after this winter, but allergies can't be taken lightly, particularly as they grow more aggressive.
One study published in 2011 predicts that pollen counts will double by 2040; allergy season will begin about a week earlier, according to the U.S. Department of Agriculture.
That's why it's a good idea to get ready, a task made easier by natural allergy specialist Susanne Bennett, author of The 7-Day Allergy Makeover.
To give Americans a better understanding of seasonal, environmental, food and other types of allergies, Bennett lists five key facts and trends about allergies you may not know about:
More half of all Americans experience allergies. "Most Americans are allergic to something: pollen, dander, dairy products, gluten and mold are just a few of the most common allergens," Bennett says. "If you don't suffer from allergies to these or other compounds, you are actually in the minority. Yet countless people think that their low energy, problems with digestion or headaches are 'normal' when in fact they may be the signs of undiagnosed allergic reactions."
Allergies aren't always "visible." It's a common mistake to associate all allergies with the symptoms of hay fever (runny nose, water eyes) on the one hand or severe inflammation (as in people with shellfish or peanut allergies) on the other, Bennett says. "In the case of allergic sensitivities, you may have low-grade, persistent reactions that wear the body down over time, making it more susceptible to future allergies," she says. "Low energy, joint pain, brain fog, headaches, inexplicable anxiety and poor digestion can all be the result of allergies."