There are many sports restricted to players of a certain age (e.g. 16 and under, 18 and under, etc.) What if a person is older and fakes his birth certificate to say that he is younger? Is there any way to expose this person?

Can we determine such a person's age by radiocarbon dating methods or other means?

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    $\begingroup$ Have you read the Wikipedia article? In the very first paragraph it states that the object to be tested must be dead, as it stops exchanging carbon with the environment. So, no. $\endgroup$
    – MattDMo
    Nov 17, 2014 at 23:05
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    $\begingroup$ You'd have to kill them first… $\endgroup$
    – canadianer
    Nov 17, 2014 at 23:08
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    $\begingroup$ Even if possible C14 dating would not be sensitive enough as the resolution (see wiki: en.wikipedia.org/wiki/Radiocarbon_dating#Errors_and_reliability) is about 80 years :) $\endgroup$
    – AliceD
    Nov 17, 2014 at 23:09
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    $\begingroup$ If you dated a person for long enough, I hope they'd tell you their real age eventually. Sometimes I think biologists should get out more. $\endgroup$ Nov 20, 2014 at 18:40

2 Answers 2


No, one can't confirm age by carbon dating. That doesn't mean we can't make a decent guess by other methods.

There is an interesting case of a 33 year old Texas woman who enrolled in 10th grade in Texas. She said she had no transcripts because she had been homeschooled. She looked like a teenager and acted like a one too. She even fooled her new 23 year old boyfriend. So it happens. It also happened in the Little Leagues World Series, if I remember correctly. A twenty-something guy passed himself off as a 14 year old. He was a star (for a while).

In children and adolescents, the combination of a dental exam, dental films and bone X-rays can narrow a one's biological age well. Once the bones are done growing in length, that avenue is closed.

After that, someone might have to provide a tooth. Chemical analysis of tooth dentin, such as aspartic acid racemization, has shown reproducible and fairly precise results.

Global levels of carbon-14 (14C) have been carefully recorded over time. In one 2010 study, forty-four teeth from 41 individuals (one per individual) were analyzed using aspartic acid racemization analysis of tooth crown dentin or radiocarbon analysis of enamel. Teeth from individuals with dates of birth ranging from 1936 through 1994 (aged 13–70 years) were analyzed, and where the date of birth was known, yielded a 14C-based date of birth estimation accuracy of 1.3 years (S.D. = 0.9 years). In one case, a date of birth was determined to be 1948.4. In another, it was determined to be 1988.

[T]en of these were split and subjected to both radiocarbon and racemization analysis. Combined analysis showed that the two methods correlated well (R2 = 0.66, p < 0.05). Radiocarbon analysis showed an excellent precision with an overall absolute error of 1.0 ± 0.6 years. Aspartic acid racemization also showed a good precision with an overall absolute error of 5.4 ± 4.2 years. Whereas radiocarbon analysis gives an estimated year of birth, racemization analysis indicates the chronological age of the individual at the time of (tooth extraction).

During the course of aging, l-forms of amino acids are transformed by racemization to the d-forms.

[T]he extent of racemization of amino acids may be used to estimate the age of various tissues. Of all stable amino acids, aspartic acid has one of the fastest racemization rates and is therefore the amino acid most commonly used for age estimation....[T]eeth are the tissue of choice for age estimation analysis.

Both methods have strengths and limitations.

The radiocarbon birth dating method can tell the birth date of the person regardless of the time of (extraction). However, the time window for this analysis is limited to subjects born after the early 1940s because the calculations are based on the measurement of bomb pulse-derived 14C.

Clearly this wouldn't be of too much use in people trying to pass themselves off as teens.

Some studies of aspartic acid racemization report accuracies of age ±3 years. The radiocarbon and racemization can further narrow it down.

Why did Charity Johnson pretend to be a teenager for 20 years?
Strategy for the estimation of chronological age using the aspartic acid racemization method with special reference to coefficient of correlation between D/L ratios and ages


To grab this opportunity to sum up the comments for the C-14 dating method, including those of of @MattDMo and @canadier: Theoretically spoken - Yes we can! But only after (1) killing the person and (2) waiting a few hundred years. As carbon keeps on being recycled in a living carbon-based organism, it has to be dead first. Secondly, because the margin or error is about 80 years, mainly due to the relatively long half-life of C14 (5730 years) and the variability in the C14 dating method (see wiki on C14 dating) one should wait, ideally between 1k and 1000k years. But given the error margin a few hundred years may suffice to get a rough idea. So to sum up - practically this test, although it is objective and free of subjectivity and robust to false pretenses, makes no sense as (a) a human life is about the same a the error margin of the test and (b) the competitor cannot participate in the contest after his or her life has being taken.

I am not aware of any biologoical methods to objectively measure age.


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