Contrary to popular belief, eating turkey isn't the main reason you feel sleepy after a Thanksgiving feast. Highly Pathogenic Avian Influenza — also known as bird flu — is killing layer hens and reducing the nation's egg supply.

During an avian flu outbreak, "The chance of infected poultry or eggs entering the food chain is low," the FDA said on its website in April, "because of the rapid onset of symptoms in poultry as well as the safeguards in place, which include testing of flocks and federal inspection programs."

The spread of H5N1 avian flu — which has killed millions of chickens, sickened hundreds of herds ofdairy cows and infected dozens of people in the United States — has prompted some to wonder whether eating turkey,