Overview
- Experts recommend 10–20 minutes of midday exposure on bare skin to trigger vitamin D synthesis, followed by sunscreen if staying outdoors.
- Food and fortified products help but rarely meet needs year‑round, so many people use supplements in low‑sun months, preferably vitamin D3 rather than D2.
- Higher‑risk groups include people with very dark skin, limited outdoor time, older adults, and those with autoimmune or absorption conditions, who are advised to get a 25(OH)D blood test.
- Clinicians warn against unsupervised high dosing because vitamin D is fat‑soluble and can accumulate, so supplementation should be guided by testing and medical advice.
- Rising social media interest in D3 is driving calls from experts for personalised plans instead of one‑size‑fits‑all supplementation.