While this is not exactly what we normally talk about on the blog, it is interesting, and it is vitamin-related: The news section of the Discovery Channel website has a cool story about lizards.
Scientists now believe that one of the reasons lizards bask about in the sun so much is actually for the same reason many of us do (and why we feel better after a little time out in the light) — the necessity of converting Vitamin D.
Like us, lizards have compounds in their skin which need UV exposure to be useful. Apparently though, lizards, unlike ourselves, are highly attuned to the levels of UV light they are receive.
"They were really, really good at hitting an optimum UV level," said Kristopher Karsten, a behavioral ecologist at Texas Christian University in Fort Worth. "It broadens our perspective of what they're really doing when they're sitting out there in the sun."
Perhaps since they have a bit a head start on us, dating back to the Jurassic period and all, they naturally are a little more wise to the ways of the sun. Still though, it seems balance is the key. Too much or too little vitamin D (brought on by UV exposure) is harmful. Too little and illness, slow growth, and reproductive problems occur. Too much vitamin D is toxic, whether you're reptilian or otherwise.
Until we develop such highly calibrated sun-worshiping capabilities, other methods, such as dietary supplements, are a healthy solution to our UV quandary. After all, though one might love to lie around in the sun all day, we don't really want to end up looking like lizards!
Discovery: Lizards Sunbathe For Vitamin D