How Does Our Skin Turn Sunlight Into Vitamin D?
Look at that guy, he thinks he’s plants! Howdy vitamen, vitawomen, and everyone in
between, Trace here with some brain nutrition for DNews. Vitamin D is everywhere in our
diets these days, sort of. You can get it in cereal, milk, orange juices and other fortified
foods, as well as in fatty fish, egg yolks and a few other places. But, mostly, vitamin
D comes from YOU. From your skin. You MAKE it. Vitamin D is actually a group of five fat-soluble
molecules, and in it’s main animal version, Vitamin D3, it promotes absorption of calcium
for our bones. Without vitamin D, adults can experience osteomalacia — pain and weakness,
and children can develop rickets: a softening of the bone’s growth plates which can lead
to bowed legs. Bottom line, D3 is real important. But let’s get back to this skin thing. Plants
have photosynthesis, right? Well, we have dermal vitamin synthesis! Deep in the skin
is a steroid called 7-dehydrocholesterol, and when it’s hit by UV B from the sun, the
sun’s photons break one of its chemical bonds, which converts to cholecalciferol — the science
name for vitamin D3! Once the D3 is created, the liver and kidneys convert it to it’s final
form: calcitriol! Whew. It’s a process, but it all starts with exposure from a nuclear
fusion ball millions of miles away. Once created in the kidneys, a protein called
DBP — or vitamin D binding protein — grabs it and transports it to the organs where it
starts cascade of effects from building bones by balancing the calcium and phosphate in
the body, to maintaining nervous system function. Vitamin D is even essential in helping DNA
to express between 100 and 1250 genes! There are also studies which hypothesize Vitamin
D or calcitriol helps treat autoimmune diseases, diabetes, infections, cognitive degeneration
and cancer; and can prevent heart disease! This stuff is apparently awesome! Which is
why we started putting it everywhere… Studies in Boston found in 1900, 80 percent
of children were afflicted with the skeletal devastation that is rickets. All from a lack
of vitamin D ingestion! So, in the 1930s the U.S. government asked food companies to add
cod liver oil, or vitamin D, to their products in a process called fortification; hoping
to eradicate the problem! Milk and cereal producers have been adding vitamin D to their
moo juice and flakes ever since! It worked as rickets has been virtually eliminated in
the West today. The thing is, remember, there are FIVE FORMS
of vitamin D. And food processors don’t add D3, the stuff we make in our bodies, they
add a different version: D2 — ergocalciferol. PLANT vitamin D, not animal. Allegedly, our
body treats them both the same, though that debate is ongoing, with some scientists saying
it’s less efficient for the body to convert, so you need more than if you just went outside.
You can get all the D3 you need with as little as 5 to 15 minutes of direct sunlight on your
“hands, arms, and face.” So, for allllll the chatter and praise vitamin
D gets from the media, you can just make it. However, if you’re worried, YES. you can have
too much, but it’s hard. Vitamin D toxicity is more a risk for people taking vitamin supplements.
And can cause an increase calcium levels which results in heart arrhythmias, decreased appetite
and increased urination. It can even cause nausea, vomiting, disorientation and the like.
Your body is trying to get all that excess calcium OUT. But, you’d have to drink more
than 40 cups of milk per day to exceed the maximum daily dose So, it’s more important
to be careful with calcium supplements, which are also D2, again not D3… they work, but
remember, debate. Vitamin D is just one of many vitamins and
minerals the body needs every day. It really struck me that the process of making it from
the sun is so complicated! Evolution is amazing. Speaking of all those vitamins… do they
REALLY improve Do you stand in the sun for 5 minutes a day?
Or would you rather just take a pill or drink a bit of milk?