You might be surprised to learn that food allergies can start in adulthood and involve a food you’ve eaten without a problem for your entire life.

For adults as well as kids, the top – but not the only – food culprits are eggs, milk, peanuts, tree nuts, fish and shellfish, wheat and soy, according to the American College of Allergy, Asthma and Immunology.

Just as with childhood food allergies, you’ll need to do your best to avoid these foods and be prepared in case you inadvertently come into contact with one of them.

Signs of a severe allergic reaction

• Hives or pale/bluish skin tone
• Cramps and/or vomiting
• Trouble swallowing or swelling of the tongue
• Weak pulse
• Feeling dizzy or faint
• Shortness of breath, wheezing or coughing
• Inability to breathe, and drop in blood pressure

The most serious reaction is called anaphylaxis, an extreme inability to breathe that can lead to shock. It is a life-threatening emergency. Keep in mind that allergic reactions can be unpredictable. Most happen within a few hours of contact, but some are instantaneous. It could take only a small amount of the allergen to cause swelling, hives or anaphylaxis. Also, your body could experience more than one type of reaction – your skin, gastrointestinal tract, heart and/or breathing could be affected.

So it’s important to call your doctor and ask about testing after any out-of-the-ordinary reaction to a particular food. If possible, write down what you ate, how soon afterward symptoms started and how long they lasted.

Allergy testing usually involves a combination of skin pricks and blood tests. Sometimes there may be a workaround. For instance, if a raw fruit or vegetable causes a reaction, you may be able to eat the food cooked because, for some people, heat neutralises the allergen.

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