What is it with red cars, red dresses, red lipstick and other sexy red things? Why red? Why not orange or blue or purple? -- Stanley, 22, Elizabethtown, PA 

Red is a powerful color for lots of reasons. Red is the color of blood, for one thing, which is a vivid connection in itself. But sexual arousal involves blood flow to the genitals, which become more red as a result. So red is also directly associated with sex.

Humans may have other reasons to find red arresting. Many fruits are red when they are fully ripe, which may be why the ability to detect red was selected for in primates and, then, in us (some carnivores, such as dogs, can’t detect red).  Interestingly, red in nature also often advertises poisonous plants or berries, so red also symbolizes danger.

Add up all of these deeply powerful connections and you can see why red has such an enduring place in human societies world wide.

Dr. Harry Fisch is a board certified urologist. He’s here to answer reader questions in an effort to get guys to “man up about health.”

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