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The Doctors answer a question from a viewer who wants to know if there is a correlation between foot size and penis size and whether there is a way to figure out the size of someone's manhood before seeing him naked.

Watch: New Shot to Boost Your Manhood?

Urologist Dr. Aaron Spitz and author of "The Penis Book" tells us he has examined over 30,000 men and their anatomy and says he looks at 50 to 80 penises per week. He says whether someone has big feet or small feet, is tall or short, skinny or fat that he sees "no correlation" to those attributes and penis size.

Dr. Spitz says there is no way to determine size without simply seeing the anatomy. He also notes that the size of a flaccid penis does not always indicate the size when erect.

Watch: Do Men Lie About Their Size?

As for the average size of an erection, Dr. Spitz says it is 5.5 inches and notes that anywhere between 4.8 inches and 6.2 inches is considered "normal."