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Vitamin D after 50 — the cheap fix most people get slightly wrong.

Low vitamin D is genuinely common after 50, and correcting it is cheap and well-tolerated. But the dose, the D3-vs-D2 question, and the K2 add-on trip people up. Here's the simple, evidence-based version.

AF
After Forty Feel EditorialUpdated June 2026 · independently chosen
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30-second version. Choose D3 (cholecalciferol), not D2 — it raises blood levels more reliably. A common maintenance dose is 1,000–2,000 IU/day, but the right number depends on your blood level, so a 25-OH vitamin D test first is the smart move. Take it with a fatty meal. K2 is optional and lower-evidence. Don't mega-dose.

Why it matters after 50

Skin makes less vitamin D with age, and low levels track with bone loss, fatigue, and immune issues. It's one of the few deficiencies that's common, easy to test, and cheap to fix — which is exactly why it's worth getting right rather than guessing.

ChoiceVerdict
D3 (cholecalciferol)Buy this — raises levels reliably
D2 (ergocalciferol)Weaker; usually prescription
Mega-doses (10,000+ IU)Skip unless a clinician directs
Top pick

Plain vitamin D3, 1,000–2,000 IU

A simple D3 softgel taken with a fatty meal. Test your 25-OH level first so you're dosing to a target, not a guess.

Compare vitamin D3 →
Optional

D3 + K2 combo

K2 is theorized to help direct calcium to bone; the evidence is thinner than for D3 alone. Reasonable if you want it, not essential.

See D3 + K2 →

Frequently asked

D3 or D2?
D3 — it raises and maintains blood levels more effectively.
How much?
Often 1,000–2,000 IU/day for maintenance, but dose to your blood test, not a guess.
Do I need K2?
Optional and lower-evidence; D3 is the priority.