The claim that people eat or swallow spiders in their sleep frequently is a widespread myth with no scientific basis. The idea that humans eat an average of eight spiders per year is false. In reality, most people swallow zero spiders in a year, and the likelihood of swallowing even one spider while sleeping is extremely low due to spiders avoiding humans and the natural movements and breathing of people during sleep.

A recurring joke or hypothetical average of "eight spiders per year" sometimes circulates, but this mostly stems from misunderstandings and exaggerations rather than fact. Some statistical estimates involve fictional or extreme outliers (like the so-called "Spiders Georg") to calculate an average, not actual recorded data of spider ingestion by humans.

In conclusion, the answer is that on average, people do not eat spiders annually while asleep or consciously, and the commonly cited number of 8 spiders per year is an urban legend.