TheScience.

Plain-language research on Vitamin D: insufficiency, absorption, sleep, mood, performance, longevity. Every claim tied to a published study.

safety
Can You Take Too Much Vitamin D?
Aug 2026
health
Sleeping Eight Hours and Still Tired?
Aug 2026
absorption
Calcium and Vitamin D: Why One Doesn't Work Without the Other
Aug 2026
ingredients
What's Actually in the Bottle
Aug 2026
fitness
You train five days and you're still probably low
Aug 2026
timing
Vitamin D and Magnesium: Why They Work Together
Aug 2026
absorption
Is Vitamin D the Same as D3?
Aug 2026
health
What the Research Says About Vitamin D and Hair Loss
Aug 2026
dosage
What 50,000 IU of Vitamin D Is Actually For
Aug 2026
health
Vitamin D, Muscle, and Metabolism for Women Over 40
Aug 2026
fitness
Vitamin D: Injury Risk and Missed Training
Aug 2026
k2
Does K2 Actually Improve Bone Density?
Aug 2026
k2
MK-7 vs MK-4: Which Form of K2 Should You Take?
Aug 2026
health
Vitamin D and Hashimoto's: Antibodies, Testing, and what the Evidence shows
Jul 2026
safety
Does Vitamin D Cause Constipation? What the Research Says
Jul 2026
k2
Why Take K2 With Vitamin D3?
Jul 2026
health
Why Vitamin D Is Crucial for Women Over 40
Jul 2026
timing
Why Consistency Is the Hard Part of Vitamin D
Jun 2026
ingredients
What's Actually in Your Vitamin D Supplement
Jun 2026
health
Can You Get Enough Vitamin D From the Sun?
Jun 2026
absorption
Liquid vs Capsule Vitamin D
Jun 2026
timing
The Best Time to Take Vitamin D
Jun 2026
low
Signs You Might Be Low on Vitamin D
Jun 2026
dosage
How Much Vitamin D Should You Take?
Jun 2026
absorption
Vitamin D3 vs D2: Which Is Better?
Jun 2026
ingredients
How to choose a Vitamin D supplement
Jun 2026
health
The Real Link Between Vitamin D and Testosterone
Jun 2026
health
What Vitamin D has to do with Cortisol
Jun 2026
health
What Vitamin D at 39 Predicted About Brains 16 Years Later
May 2026
health
What a Four-Year Vitamin D Trial Found About Aging
May 2026
health
Vitamin D And Sleep: What The Research Shows
May 2026
absorption
Why Vitamin D Needs Fat To Be Absorbed
May 2026
health
Why Vitamin D Matters For Men Under 35
Apr 2026
low
Why 70% Of Americans Are Low On Vitamin D
Mar 2026
low
Why Modern Life Lowers Your Vitamin D
Mar 2026
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