# Is There Any Test To Date A Person's Age **URL:** \ **Category:** Factual Questions\ **Created:** [October 25, 2008, 5:34am UTC](https://boards.straightdope.com/t/is-there-any-test-to-date-a-persons-age/469482 "2008-10-25T05:34:28Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![Markxxx](https://avatars.discourse-cdn.com/v4/letter/m/5daacb/32.png) [@Markxxx](https://boards.straightdope.com/u/Markxxx)\ **Post date:** [October 25, 2008, 5:34am UTC](https://boards.straightdope.com/t/is-there-any-test-to-date-a-persons-age/469482/1 "2008-10-25T05:34:28Z")
Obivously you couldn’t do it exactly, but within a range. I’m talking about a scientific test. For instance if I just presented you with a person, could you do any medical test, or scientific test, to approximate an age. In other words if I present you with a person you could say, "this person is between 80-85. I’m thinking things like maybe looking at teeth and saying “OK the wear indicates at least 50 years of age.” Or something like that. I guess I mean something like radiocarbon dating for live people ---
**Author:** ![Enright3](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/enright3/32/2897_2.png) [@Enright3](https://boards.straightdope.com/u/Enright3)\ **Post date:** [October 25, 2008, 5:46am UTC](https://boards.straightdope.com/t/is-there-any-test-to-date-a-persons-age/469482/2 "2008-10-25T05:46:03Z")
Can’t you cut off their arm and count the rings? 😃 I know it’s an old joke but it continues to be one of my favorites. ---
**Author:** ![Washoe](https://avatars.discourse-cdn.com/v4/letter/w/ecae2f/32.png) [@Washoe](https://boards.straightdope.com/u/Washoe)\ **Post date:** [October 25, 2008, 5:57am UTC](https://boards.straightdope.com/t/is-there-any-test-to-date-a-persons-age/469482/3 "2008-10-25T05:57:00Z")
My father told me that Linus Pauling once assigned a graduate student the task of searching all applicable and available literature to determine if there were a viable method of doing this. At that time there wasn’t. I’ve never heard this anecdote from anybody else, and I don’t know any more about it than just that fact. If anybody else knows more about this, please speak up. AFAIK, it is now possible to pinpoint a person’s age by measuring the racemization of aspartic acid in their teeth. Apparently this is done by measuring the ratio of the dextro and levo enantiomorphs, which changes in a constant and predictable manner throughout a human’s lifespan. The other night I was watching a crime drama in which the coroner glibly announced to the investigating detectives that she had determined the victim’s exact age by measuring the amount of blah blah blah in the vic’s eyeball. Don’t know anything about it, but if nobody else comes forward, I’ll dig through the TiVo trash and see if I can find it. I think it was SVU—the episode that was on last week about the murdered female astronaut. ---
**Author:** ![PopeJewish](https://avatars.discourse-cdn.com/v4/letter/p/ce7236/32.png) [@PopeJewish](https://boards.straightdope.com/u/PopeJewish)\ **Post date:** [October 25, 2008, 6:57am UTC](https://boards.straightdope.com/t/is-there-any-test-to-date-a-persons-age/469482/4 "2008-10-25T06:57:41Z")
I’m not too knowledgeable about this sort of thing, but theoretically you could do it by measuring something like the DNA. Also, I’ve read something about cells being hardcoded to divide something like 52 times (my brother was also telling me about this, he’s much smarter than I am, hehe) so I suppose you could figure out by calculating the cell division. I’ve also heard that the sperm of a 28-30 year old man has only gone through something like 300 generations whereas the sperm of a 50 year old has gone through nearly a thousand. That said, if they can measure that sort of thing one would imagine they can reverse the process (the article was about how human evolution is slowing because older men aren’t having children as much, on top of the whole more people living to adulthood thing) ---
**Author:** ![Apex\_Rogers](https://avatars.discourse-cdn.com/v4/letter/a/e480ec/32.png) [@Apex\_Rogers](https://boards.straightdope.com/u/Apex_Rogers)\ **Post date:** [October 25, 2008, 7:08am UTC](https://boards.straightdope.com/t/is-there-any-test-to-date-a-persons-age/469482/5 "2008-10-25T07:08:44Z")
> [@PopeJewish](#): > > I’m not too knowledgeable about this sort of thing, but theoretically you could do it by measuring something like the DNA. Also, I’ve read something about cells being hardcoded to divide something like 52 times (my brother was also telling me about this, he’s much smarter than I am, hehe) so I suppose you could figure out by calculating the cell division. I’ve also heard that the sperm of a 28-30 year old man has only gone through something like 300 generations whereas the sperm of a 50 year old has gone through nearly a thousand. That said, if they can measure that sort of thing one would imagine they can reverse the process (the article was about how human evolution is slowing because older men aren’t having children as much, on top of the whole more people living to adulthood thing) I think what you’re describing relates to [telomeres](http://en.wikipedia.org/wiki/Telomere). The wikipedia page has a nice summary: > [@](#): > > A telomere is a region of repetitive DNA at the end of chromosomes, which protects the end of the chromosome from destruction. Its name is derived from the Greek nouns telos (τἐλος) “end” and merοs (μέρος, root: μερεσ-) “part”. > > During cell division, the enzymes that duplicate the chromosome and its DNA can’t continue their duplication all the way to the end of the chromosome. If cells divided without telomeres, they would lose the end of their chromosomes, and the necessary information it contains. (In 1972, James Watson named this phenomenon the “end replication problem”.) The telomere is a disposable buffer, which is consumed during cell division and is replenished by an enzyme, the telomerase reverse transcriptase. > > In 1975-1977, Elizabeth Blackburn, working as a postdoctoral fellow at Yale University with Joseph Gall, discovered the unusual nature of telomeres, with their simple repeated DNA sequences composing chromosome ends. Their work was published in 1978. > > This mechanism usually limits cells to a fixed number of divisions, and animal studies suggest that this is responsible for aging on the cellular level and affects lifespan. Telomeres protect a cell’s chromosomes from fusing with each other or rearranging. These chromosome abnormalities can lead to cancer, so cells are normally destroyed when telomeres are consumed. Most cancer is the result of cells bypassing this destruction. Biologists speculate that this mechanism is a tradeoff between aging and cancer. ---
**Author:** ![WhyNot](https://avatars.discourse-cdn.com/v4/letter/w/c77e96/32.png) [@WhyNot](https://boards.straightdope.com/u/WhyNot)\ **Post date:** [October 25, 2008, 10:43am UTC](https://boards.straightdope.com/t/is-there-any-test-to-date-a-persons-age/469482/6 "2008-10-25T10:43:30Z")
With children and teens, you can get a fairly accurate estimate by looking at the epiphyseal growth plates in the bones. When we’re born, some of our “bones” are still cartilage, and those areas are slowly replaced by actual bone. Measure the still-cartilage area, and you can estimate how much growth is left, and thus the likely age of the individual. You can do this with an x-ray (or, of course, CT or MRI, 'though those are more expensive). I know the facial bones keep growing throughout life (according to my current A&P teacher, anyhow), but I don’t know if they do so consistently enough to be a good age marker. ---
**Author:** ![Washoe](https://avatars.discourse-cdn.com/v4/letter/w/ecae2f/32.png) [@Washoe](https://boards.straightdope.com/u/Washoe)\ **Post date:** [October 25, 2008, 7:33pm UTC](https://boards.straightdope.com/t/is-there-any-test-to-date-a-persons-age/469482/7 "2008-10-25T19:33:51Z")
You guys just _had_ to make me dig through the DVR recycle bin, didn’t you? It was carbon-14 in the lens of the vic’s eye. The ME placed her age down to the month. ETA: [Carbon-14 - Wikipedia](http://en.wikipedia.org/wiki/Carbon-14#Carbon-14_and_nuclear_tests) ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [October 25, 2008, 10:41pm UTC](https://boards.straightdope.com/t/is-there-any-test-to-date-a-persons-age/469482/8 "2008-10-25T22:41:19Z")
I don’t know if there’s any part of the human body that can be carbon-dated (it’d have to be something that is made once and never replenished), but there’s no way you could carbon date anything down to the month. The usual standard is about 50 years, and it’d be even worse for anything after July 1945.