The Sunshine Vitamin: Why You Need It & How to Get Enough (Even in Winter!)
Even though we've had plenty of sunshine here on the California Central Coast so far this year, the chillier days mean less time outdoors. And that got me thinking about Vitamin D.
Not just a vitamin—it's a hormone, too!
Vitamin D is a total multitasker. It’s both a fat-soluble vitamin and a hormone, playing a crucial role in everything from bone health to immune function. While you can get it from sun exposure, food, and supplements, none of those forms are instantly ready to go. Your body still has to convert them into the active form—Vitamin D3 (cholecalciferol)—before they can actually do their job.
Food Isn’t Enough
Don't kill the messenger, but getting enough Vitamin D from food alone? Not gonna happen. Very few foods contain high enough amounts to meet your daily needs, which means your best bet is to step outside and soak up some sunshine.
But here’s the tricky part—there’s no one-size-fits-all rule for sun exposure. Factors like skin tone, age, latitude, and how much skin you actually have exposed all play a role. According to the Vitamin D Council, your body can produce 10,000–25,000 IU in just the amount of time it takes for your skin to turn slightly pink. Wild, right?
Here’s how it works: Ultraviolet B (UVB) rays from the sun convert cholesterol (7-dehydrocholesterol) in your skin, kicking off a two-step activation process. First, your liver turns it into 25-hydroxyvitamin D, then your kidneys convert it into the active form, 1,25-dihydroxyvitamin D (aka Vitamin D3, or cholecalciferol).
Why Does Vitamin D Matter?
Vitamin D influences anywhere from 200 to 3,000 genes in your body and plays a role in:
Calcium metabolism (hello, strong bones!)
Hormone balance
Muscle function
Immune system support
Cancer prevention
Mental health
And that’s just the highlight reel.
Our lifestyle isn't helping
It seems like it shouldn’t be too hard to get out in the sun for a bit a few times a week, but life happens! Whether you work in an office under fluorescent lights all day or you’re a nonstop homeschooling mom juggling schedules, appointments, enrichment classes, and football practice, chances are, outdoor time isn’t high on the priority list.
And let’s not forget an entire generation was duped into believing that fat was the enemy (do you remember, fat-free everything?) and that sunscreen should be slathered on like frosting. When you add up the lack of healthy sun exposure and years of diet misinformation, it’s no wonder so many people are running low Vitamin D. Makes sense now, right?
Deficiencies
Rickets
Schizophrenia
Depression
Hormone imbalance
Autoimmune diseases
On the other hand, it is possible to get too much Vitamin D, which is why it’s so important to have adequate levels of Vitamins A and K2 which protect against Vitamin D toxicity. All three of these fat-soluble vitamins work synergistically, along with other cofactors like magnesium and boron.
What helps with the absorption of VItamin D?
The above cofactors help and since Vitamin D is a fat-soluble vitamin, it needs fat to be absorbed.
How do I make sure I’m getting enough Vitamin D?
Eat Vitamin D Foods:
Fatty fish (salmon, mackerel)
Cod Liver Oil
Egg yolk
Beef Liver
Raw cheese
Mushrooms (D2)
Get out in the sun
If you can, aim to get outside between 10:00 AM and 3:00 PM for about 15-20 minutes, two to three times a week, with your arms and legs exposed (weather permitting). But let’s be real—it’s winter, and unless you’re one of those brave souls who enjoys freezing for the sake of wellness, getting enough sun can be tricky. Personally, as a self-proclaimed wimpy California girl, you won’t catch me sunbathing in the cold. So, this is when I turn to supplements to keep my levels up.
Supplement
If you need a some extra support, take a D3 supplement. Check out my Vitamin Support on Fullscript.