When I was a kid or a teenager, my skin would heal from minor scratches almost immediately. A scratch (like from walking through brambles, which I did all the time) would heal up in maybe a day and a half or two days. Then, sort of all at once, when I was about 24 or 25, suddenly it took twice as long. I noticed it when I was living in Utah and hiked a lot in the mountains and deserts, and would get similar scratches, which would now take three or four days to heal.
I figured I was just getting old, and it would just keep getting worse. But it did not. Instead, it stayed like that for thirty-five years. However, just in the past year or two—since I reached my 60s—I’ve observed a fresh doubling in wound-healing times. Now a minor scratch takes a week to heal.
The surprise here is not that the speed of healing declines as one gets older, but the weird stepwise nature of the change—stability for decades, and then an abrupt doubling in time to heal.
I don’t know if that will continue. Maybe I’ll continue to heal at this rate until I’m 105 or so?
I’ve documented this largely for my brother, who once expressed appreciation for the fact that having an older brother gave him a four-year heads-up for this sort of age-related change. (I’m not sure he appreciates it as much now as he did in his 30s and 40s.)
I looked for some research studies as to whether my observation points to a more general phenomenon, but wasn’t able to find much. My brother found a study, which says in part:
The rate of epithelialisation appears to be different in older persons, but the magnitude of the delay may not be clinically important.THOMAS, D. R. Age-Related Changes in Wound Healing. Drugs & Aging, [s. l.], v. 18, n. 8, p. 607–620, 2001. DOI 10.2165/00002512-200118080-00005.
I guess, as long as you do eventually heal up, the length of time it takes is “not clinically important,” but it’s still kind of a drag to be wounded for week(s).