9 Surprising Allergy Triggers

The cause of your sneezing, itchy nose, watery eyes, headache and a host of other symptoms may be more surprising than you think. You already know the usual suspects: pet dander, mold, pollen and dust. But could something else be causing your allergy symptoms? Our experts say yes indeed. Check out our list of allergens and allergy triggers you may have never before considered.

1. Chocolate

For some people, eating chocolate can be as uncomfortable as standing in a field of pollen during the peak of spring. Your favorite chocolate bar can bring on classic allergy symptoms, says Steven Y. Park, MD, an otolaryngologist in private practice in New York and the author of Sleep, Interrupted: A Physician Reveals the #1 Reason Why So Many of Us Are Sick and Tired. "Chocolate can irritate your nose's nervous system," he says. "Think of it as being like a migraine, where nerve endings in your nose become overly reactive." Incidentally, he adds, chocolate, along with red wine, MSG and aged cheeses, is a known migraine trigger.

2. Cloudy Weather

A lot of people complain about feeling a little down when the sun is hiding, but could clouds and rain actually bring on allergies? Certified food allergy safety educator Aleasa Word in Newark, Delaware, says yes. "When the weather changes and it gets cold, my 9-year-old son breaks out in hives and eczema on his hands and legs," she says. "We have to make sure he has several layers on to reduce the effect, and he takes an antihistamine medication each day before going out in the cold weather." Weather fluctuations such as temperature, air pressure and humidity changes can absolutely bring on allergy symptoms, adds Ronald Stram, MD, founder of the Center for Integrative Health and Healing in Delmar, New York. "This is also a common reason for sinus pain, pressure and headaches, which are often treated as if you had a sinus infection."

3. Stress

Have you ever been so stressed out that you started sneezing? It happens, says Elizabeth Lombardo, PhD, MS, PT, a psychologist in private practice in Wexford, Pennsylvania. "Stress induces a physiological reaction of certain chemicals including histamines, which lead to allergy symptoms. And although stress doesn't actually cause allergies per se, research shows it can make allergy symptoms much worse: immediately and even the next day."

4. Sperm

Allergic to sex? Maybe. According to experts, as many as 40,000 women in the United States suffer from what is known as seminal plasma hypersensitivity, an allergy to semen that can cause hives, itching, swelling and breathing difficulties. In severe cases, it can even cause death. "This occurs when the body's immune system overreacts when it encounters semen," says Dr. Stram. "The white blood cells mistakenly identify proteins in the semen as harmful invaders, such as bacteria or viruses, and launch an attack against them." What to do if you suspect a sperm allergy? Use condoms, of course, but also speak to a doctor immediately to rule out other sexually transmitted infections. To learn more about unusual physical responses to sex, check out 9 Surprising Post-Intercourse Reactions.

5. Cell Phones

We spend so much time with our cell phones that it's no wonder doctors are reporting an uptick in so-called cell phone "allergies." Some people may be surprised to find out that the rash on their cheek is from an allergy to nickel, which some phones are coated in. For others, it may just be a case of garden-variety contact dermatitis. This inflammation of the skin, explains Dr. Stram, is generally benign, but can cause red, itchy bumps. While the situation can most easily be traced to a dirty phone (remember to gently wipe yours with a disinfecting wipe every few days), the cause could also be diet related. "There is evidence that skin sensitivity may be a result of deficiencies in nutrients such as essential fatty acids, zinc, vitamin D and probiotics."

6. Wine

Love pinot noir, chardonnay or merlot? For some, even just a little sip can bring on red, blotchy skin and flu-like symptoms. But can one really be allergic to wine? Yes, says Dr. Stram. "This can be [the result of] several different allergies or sensitivities," he explains. "People who are allergic to wine can be allergic to yeast, sulfites, phenols or to the grapes themselves. The white blood cells mistakenly identify proteins in the wine as harmful invaders, such as bacteria or viruses, and launch an attack against it." But if you're a new wine drinker, don't expect your body to react immediately—wine allergies can take time to develop. "Typically, an allergic response is not triggered the first time the body encounters the protein, or allergen," he says. "The first time or several times after the body is exposed to the allergen, the immune system becomes sensitized."

7. Perfumes and Colognes

Does a certain coworker's cologne make your eyes burn? Do you sneeze every time you pass by his desk? If so, you may have scent sensitivities. According to some estimates, as many as a quarter of the U.S. population suffers from allergic rhinitis. Symptoms can include watery eyes, sneezing, runny nose and even difficulty breathing. "This is due to an extra-sensitive nervous system in your nose that overreacts to certain stimulants," says Dr. Park. Perfumes have become such an issue that some workplaces have banned them entirely. For instance, after an employee said that her colleague's perfume made it "challenging" to do her job, the city of Detroit made a new rule: no scented body products, aftershave, perfumes or colognes allowed.

8. Houseplants

They supposedly purify the air in our homes, but that neglected houseplant in the corner of your living room may also bring on a bad case of hay fever, say experts. According to researchers in Belgium, exposure to certain plants can cause sneezing and a runny nose. If you're sneezing more than usual this season, consider setting your houseplants outside for a day or two to see if your allergies improve. The worst-offending plants? Palms, orchids, ficus and ferns are known to be the biggest allergy inducers.

9. The Sun

Cloudy weather isn't the only allergy culprit, according to experts. For some people, the sun can bring on painful rashes and hive-like bumps. It's a condition commonly called a "sun allergy," but its true name is photosensitivity. "This occurs when the body's immune system overreacts to sunlight exposure," says Dr. Stram. "The sun causes a reaction in the skin which changes the protein component of the skin, producing an inflammatory cell reaction which releases histamine. Chemicals in lotions, perfumes or oral medications (like antibiotics or diuretics) may also prompt the allergic reaction." If you suspect you have a sun allergy, talk to your doctor, who may recommend changing your medications or trying something called "phototherapy" treatment, which can help your skin build up a tolerance to the sun's rays.

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