Our Story · D3X · Why Vitamin D, Why Now
don't have
enough Vitamin D
Nobody's talking about it. We are.
A problem
hiding in plain sight
Most Americans don't have enough Vitamin D.1 Almost none of them know it. The fix isn't more products. It's products people actually take.*
That's why we built D3X. One bottle. One habit. Every day.
Five reasons
we ended
up here
It's not one thing. It's modern life, biology, and geography. Most of us are running into all of them at once.
01
Indoors most of the day3
Desks, screens, cars. Direct sun on bare skin is rare in a typical week, and Vitamin D synthesis only happens when UVB hits exposed skin.
02
Diet doesn't provide much2
Almost no foods naturally contain meaningful amounts of Vitamin D. Fatty fish and egg yolks contain some, but you'd need to eat them daily to come close to enough.
03
Frequent sunscreen use3
Even SPF 15 blocks the majority of the UVB rays your skin needs to produce Vitamin D. The dermatology guidance to wear sunscreen daily is necessary for skin cancer prevention, and it's a major reason Vitamin D status has dropped in the population.
04
Skin pigmentation2
Higher melanin levels naturally reduce how efficiently the skin produces Vitamin D from sunlight. Insufficiency rates are especially high in populations with darker skin tones living at higher latitudes.
05
Winter and latitude3
Above approximately 37° latitude, the sun's angle in winter is too low for UVB rays to penetrate the atmosphere effectively. Most of the United States, including all of New England, the Midwest, the Pacific Northwest, and much of California, sits above that line.
Making daily
Vitamin D
effortless
The supplement only works if you actually take it. We design every part of the product around that one fact.*
- Take it anywhere, anytime. No meal needed.
- Add it to your coffee, smoothie, or directly under the tongue.
- Auto-renews on a schedule, so you never run out.
- Perks for staying consistent.
Raising
awareness
at scale
Most people don't know they're low. We talk about Vitamin D the way friends talk about it. Short, clear, and where people actually scroll.
- We translate the science into everyday language.
- We partner with creators to spread the message.
- We build content for TikTok and Instagram first.
- We interact directly with our community.
Why Vitamin D
matters
Vitamin D has been studied for over a century. The core science is settled, and there's a lot more being learned every year.*
What we know
- Hormone-like mechanism.Your body converts Vitamin D into an active form that acts like a signaling hormone.2*
- Receptors across the body.It works through receptors found in many tissues, not just one organ.2*
- Gene regulation.It influences gene activity and cellular behavior across the body.2*
- Core functions established.Calcium absorption, bone health, immune function, muscle function.2*
Where it's heading
- Mental health.Researchers continue studying how Vitamin D status relates to mood and stress resilience.4*
- Sleep.Ongoing work looks at links between Vitamin D and sleep quality and recovery.5*
- Physical performance.Studies explore Vitamin D's role in muscle performance and athletic outcomes.6*
- Focus and cognition.Researchers are looking at potential links to focus and brain health.7*
- Longevity signals.Large studies are exploring biological aging markers, including telomeres.*
Want the latest science and study breakdowns?
Read the science →Sources
Every health claim on this page is backed by peer-reviewed research. Tap any reference to read the original study.
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1
Vitamin D deficiency and insufficiency among US adults: prevalence, predictors and clinical implicationsView study →
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2
Vitamin D DeficiencyView study →
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3
Sunlight and Vitamin D: A global perspective for healthView study →
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4
Vitamin D and Depression: meta-analysis of 31 trials, 24,189 participantsView study →
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5
Vitamin D and Sleep: A Systematic ReviewView study →
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6
Effect of vitamin D supplementation on muscle strength: systematic review and meta-analysisView study →
-
7
Vitamin D and Cognitive Performance in Adults: A Systematic ReviewView study →
-
8
Comparison of D2 and D3 supplementation in raising serum 25-hydroxyvitamin D: systematic review and meta-analysisView study →
Time to get
serious about
your D.
Three ingredients. One daily habit. A bottle and a blueprint, shipped free.
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