Peanut allergies and kissing: brushing not best defense


Do you know what the person who is about to kiss you ate recently? It’s worth finding out if you have severe allergies to peanuts.

Peanut allergen appears to linger in saliva right after a meal, according to research reported by the American Academy of Allergy, Asthma and Immunology. In fact, it could take anywhere from one to almost four hours or more to become undetectable.

What if the peanut eaters brush their teeth after eating? Although it’s a good strategy for their oral health, brushing teeth right after a meal didn’t impact the allergen’s level. Brushing an hour after eating did rid some of the allergen, but not all of it.

Reactions Are Possible

Allergies can cause a host of symptoms, including:

  • Itching, hives, or other skin reactions

  • Tingling in the mouth 

  • Face, tongue, or lip swelling 

  • Coughing

It’s not uncommon, however, for people with food allergies to suffer a serious reaction, known as anaphylaxis. It can cause life-threatening symptoms, such as narrowing of airways in the lungs, swelling of the throat, or a severe drop in blood pressure.

Precautions You Can Take

Larger studies and more research are needed. But the best way to avoid a reaction is to ask your partner to avoid anything containing peanuts.

If that’s not possible, wait a few hours before kissing someone after he or she has eaten a meal containing peanuts. In addition, make sure your partner has consumed a peanut-free meal and brushed his or her teeth sometime after eating the allergen. Taking the following steps also can help protect you from a reaction:

  • Alert loved ones about your allergies to prevent potential problems.

  • Scour labels to see if foods contain allergens before eating them.

  • Ask about ingredients before ordering meals at restaurants or dining at a loved one’s home. Pass on the dish if it contains anything that might trigger a reaction. Chinese, Thai, Vietnamese, and other Asian dishes are often prepared with peanuts.

If you have peanut allergies, also ask your doctor about medications that can ease symptoms if you’re exposed to the food. For instance, antihistamines can help relieve mild symptoms. Self-injectable epinephrine, such as the EpiPen, may calm emergency situations.



“Peanut Allergen Exposure Through Saliva: Assessment and Interventions to Reduce Exposure.” J.M. Maloney et al. Journal of Allergy and Clinical Immunology, 2006. Vol. 118, no. 3, pp. 719-24. Accessed 2013.

“Frightened of Food: Living with Food Allergies.” News in Health. National Institutes of Health, May 2008. Accessed 2013.

“Food Allergies: What You Need to Know.” Center for Food Safety and Applied Nutrition , U.S. Food and Drug Administration, April 17, 2013. Accessed 2013.

“Tips to Remember: Food Allergy.” American Academy of Allergy, Asthma and Immunology. Accessed 2013.

“Peanut and Tree Nut Allergies.” Allergy New Zealand. Accessed 2013.

“Guidelines for the Diagnosis and Management of Food Allergy in the United States.”American Academy of Allergy, Asthma and Immunology, December 2010. Accessed 2013.

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