From Dr. Mercola:
A runny nose, watery eyes, sore throat, sneezing and coughing are among the most common symptoms of the common cold. Yet, they’re also experienced by people with allergies. How can you tell the difference?
One of the most obvious telltale signs is a fever. Symptoms caused by a cold (or flu) may come along with a fever, but those caused by allergies do not (even though allergies are sometimes called “hay fever”). The duration of the symptoms is another clue.
Cold symptoms should resolve in two weeks or less, but allergies can hang around for much longer. The latter may persist for an entire season or even year-round, especially if you’re allergic to an indoor allergen like dust mites or mold. There are other ways of telling the difference as well.
How to Determine If Your ‘Cold’ Symptoms Are Really Allergies (or Vice Versa)
Allergic symptoms tend to flare up at certain times of day or during certain activities. An allergy to dust mites might result in waking up with congestion, for instance, while symptoms that appear primarily during your morning walk could be due to pollen.
If it’s the middle of winter and your child starts coughing and sneezing, and you know some of her friends have recently been sick, it’s probably virus-related. Age can also lend a clue. Outdoor allergies typically begin before the ages of 4 and 6 while indoor allergies may start at age 3.
If your child has eczema, there’s a good chance she also has allergies, as the two often go hand in hand (and if your child has both allergies and eczema, she may also develop asthma).1 Further, if either or both parents have allergies, your child is at an increased risk as well.
Another simple indicator is to check the mucus that’s coming out of your (or your child’s nose). Clear, water mucus may be due to allergies while thick, green mucus may be indicative of a cold.
If you suspect your child has allergies and symptoms also include wheezing, chest tightness or shortness of breath, be aware that it could also be asthma or allergic asthma (a combination of allergies and asthma).
Is Food Triggering Your Asthma Symptoms?
In allergic asthma, the same triggers that set off your allergies — pollen, pet dander, etc. — may also set off your asthma. This is also true of food allergies, although it is relatively uncommon.
You’ll know it’s occurring if you experience your typical food allergy symptoms, such as hives, rash, nausea/vomiting or diarrhea followed by coughing and wheezing. Anaphylaxis, in which your throat swells and you may not be able to breathe, can also occur.
Research has found that junk food increases a child’s risk of asthma and allergies. Food preservatives are also known to trigger asthma attacks in some people, particularly sulfites, which are found in foods like shrimp, dried fruits and wine.2 They include:
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