No, vitamin D doesn't help you tan, and a tan doesn't keep your vitamin D up for long. The same UVB light that makes vitamin D in your skin also triggers a tan, but the melanin that darkens your skin absorbs that UVB, so the more tanned you get, the slower you make more vitamin D. And by midwinter, most of what you made in summer is gone.
The short version:
- Tanning is melanin. Vitamin D supplements don't affect it.
- Sun on bare skin makes vitamin D, so a tan is a sign you probably made some.
- Melanin acts like built-in sunscreen: more of it, less vitamin D per minute of sun.
- In one study, a summer tan helped levels but couldn't hold what kids had reached with winter supplements.
- Tanning beds aren't a vitamin D strategy.
- Sun is seasonal; a dropper isn’t. D3X gives you vitamin D with no UV at all.
DOES VITAMIN D HELP YOU TAN?
No. A tan is your skin making more melanin, the pigment that protects deeper skin from UV light. Taking vitamin D doesn't feed that process or speed it up. If a supplement promises a better tan, it isn't the vitamin D doing it.
DOES A TAN MEAN YOUR VITAMIN D IS HIGH?
Sometimes, briefly. When UVB hits bare skin, it converts a cholesterol-like molecule into vitamin D3. The same light also tells your skin to make melanin. So a tan is a decent sign you've had enough sun to make some vitamin D.
But here's the twist. Melanin works by absorbing and scattering UV light, and that includes the UVB your skin needs to make vitamin D. Researchers studying skin color and vitamin D describe melanin as reducing how efficiently skin makes it. The darker your skin gets, the more sun you need for the same amount. Your tan is quietly turning down the factory that built it.
Your tan is quietly turning down the factory that built it.
DOES A SUMMER TAN LAST YOU THROUGH WINTER?
Not really. That same study measured schoolchildren's skin color and vitamin D across a summer after they'd taken vitamin D supplements over the winter. Tanning did contribute to their levels, but it wasn't enough to keep them at the level they'd reached with supplements. Vitamin D from summer sun fades over the following months, and from roughly October to March much of the US doesn't get enough UVB to make more. We went through why in can you get enough vitamin D from the sun, and why a beach week in January helps less than you'd hope in does a winter vacation boost vitamin D.
WHAT ABOUT TANNING BEDS?
Some tanning beds give off UVB, which can make vitamin D, and many give off mostly UVA, which doesn't. Either way, it's UV damage to your skin, and dermatologists don't recommend tanning beds as a way to get vitamin D. Lamps sold for winter mood are a different thing again: most filter out UV entirely, which is why SAD lamps don't give you vitamin D.
SO HOW DO YOU KEEP YOUR VITAMIN D UP?
Enjoy the sun sensibly, and don't rely on it from fall to spring. About 70% of US adults are below 30 ng/mL, tans included. A daily supplement is the reliable part: no UV, no guessing, same dose every day. Our guide to starting vitamin D for winter covers the timing.
WHY D3X
The sun does the job for a few months and then quits for the winter. A dropper doesn’t. D3X gives you the same dose every day, all year, without the UV:
- The dose the research uses: 2,000 IU (50 mcg) of D3, the daily dose 25,871 adults took for over five years in the VITAL trial, at half the upper limit.
- K2 built in: 100 mcg of K2 as MK-7, which helps direct calcium to bone.*
- The fat comes with it: dissolved in organic olive oil, so absorption doesn’t depend on what you ate.
- Nothing else: three ingredients, no seed oils, fillers or sweeteners, in amber glass.
- Checked: made in the USA in a cGMP facility and third-party tested.
- Easy to keep going: from 75¢ a day, free US shipping, and a subscription so you never run out.
Get D3X Liquid Vitamin D3 + K2 →
Sources
Sawicki CM, et al. "Sun-Exposed Skin Color Is Associated with Changes in Serum 25-Hydroxyvitamin D in Racially/Ethnically Diverse Children." Journal of Nutrition, 2016.
National Institutes of Health, Office of Dietary Supplements. "Vitamin D: Fact Sheet for Health Professionals."
Liu X, et al. "Vitamin D deficiency and insufficiency among US adults." British Journal of Nutrition, 2018.
About D3X. D3X makes one thing: a liquid vitamin D3 + K2 (2,000 IU D3 / 100 mcg K2 as MK-7) in an olive-oil base, third-party tested and made in the USA. No seed oils, fillers, or sweeteners. See the liquid vitamin D3 + K2 drops.
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
Frequently Asked
Does taking vitamin D help you tan?
No. Tanning is your skin making more melanin in response to UV light. Vitamin D supplements don't change that process.
Does a tan mean your vitamin D is high?
A tan means you've had sun, and sun on bare skin makes vitamin D, so tanned people often have higher levels in late summer. But melanin also absorbs the UVB that makes vitamin D, so the darker your skin gets, the slower it makes more.
Does a summer tan keep your vitamin D up in winter?
Not reliably. In a study of schoolchildren, tanning over the summer contributed to vitamin D levels but wasn't enough to hold the level they'd reached with supplements over the winter. Vitamin D from the sun fades over the following months.
Do tanning beds give you vitamin D?
Some emit UVB, which can make vitamin D, but many mostly emit UVA, which doesn't. Either way, UV exposure damages skin, and dermatologists don't recommend tanning beds for vitamin D. A supplement gets the vitamin without the UV.
