Comment Use an Age-verified flag (Score 1) 92
Why use a date field, which introduces all manner of privacy and anonymity issues? Instead, you could use flags: unverified, verified-minor, verified-adult. (and for further protection you could opt to leave minors at the unverified state). It might need some refinement since age restrictions vary with jurisdiction. But recording whether someone is at least over a certain age beats recording their exact date of birth.