Don’t fool around with these nuts

After eating Brazil nuts 2-3 hours prior, a man had unprotected intercourse with his 20-year-old partner who had a documented Brazil nut allergy. The woman developed urticaria, angioedema, and dyspnea. To figure out the cause of this hypersensitivity reaction, UK researchers did a skin prick test in the woman using the boyfriend’s semen both before and after eating Brazil nuts.

Apparently, some nut protein got into the semen. 

“We believe this to be the first case of a sexually transmitted allergic reaction,” the researchers wrote in the Journal of Investigational Allergology and Clinical Immunology. Of note, Brazil nuts are the second most frequent nut allergy in the United Kingdom. Unfortunately for science, the couple broke up before the investigators could confirm the results.

“Our demonstration of an allergenic Brazil nut protein in the semen clearly proves the ability of such protein(s) to resist digestion. Additionally, to enter the semen, the protein would require circulation in the blood to the prostate or other reproductive organ.”

Notably, severe allergic reactions have been demonstrated in those with crustacean allergy following exposure from kissing. Also, penicillin exposure leading to allergic reaction could occur secondary to intercourse, per the literature.

The moral of this study? If you have food allergies, you might want to find out what your partner recently ate, before you get too close