Because Sometimes More is More
In short, it varies from person to person, but those circumcised in adulthood (who have experienced it both ways) generally say it’s reduced by at LEAST half, if not more, and it gets worse with aging.
First, remember circumcision alters the penis’ sexual response in three main ways:
1. The foreskin itself has tens of thousands of unique nerve endings that are particularly receptive to light-touch and stretching. These are mostly-to-completely removed in circumcision. The frenulum, considered by many to be the most sensitive spot on their penis, is also often removed to some degree. One study indicates that the five most sensitive parts of the penis are removed in circumcision- to look at it another way, a circumcised penis only has its sixth most sensitive spot.
2. The permanent exposure of the glans results in it developing a layer of keratin (basically a callous) over time. The glans dries out, becomes rougher, and loses much of its sensitivity. Keratinization continues over time, so someone circumcised 50 years ago will have even less sensation than someone circumcised 20 years ago.
3. With the exception of very loose circumcisions, the penile skin’s natural mobility is partially or completely inhibited. It is unable to fully massage the shaft and glans, resulting in a less “deep” sensation, and without adequate lubricant, less comfortable or even painful masturbation and sex. In extreme cases, even getting an erection can be slightly uncomfortable or painful.
Needless to say, this “triple whammy” adds up. Some frequent comparisons I hear from those circumcised in adulthood, who remember what it was like to have foreskin:
-With a finger, stroke the palm of your hand, and then stroke the back of your hand. That’s the difference in sensation after circumcision.
-Some have compared intact sensation to seeing in color, and circumcised sensation to seeing in black-and-white.
-The intact glans, much like a clitoris, tends to be extremely sensitive to direct touch, and generally needs to be stimulated through its hood, the foreskin. A circumcised glans can often barely feel a finger running across it.
-Percentage-wise, if sensation with a foreskin is rated as 100%, people have rated sensation after circumcision as 50% at best, to only 10% at absolute worst.
All in all, a surgery that often removes about half of the penile skin isn’t without its consequences.