19/10/2026
Most people think vitamin D is “the sunshine vitamin for bones.”
True… but incomplete.
Vitamin D behaves more like a 'hormone' than a simple nutrient. Once it’s activated, it binds to vitamin D receptors in tissues throughout the body and influences gene expression across the immune system, gut lining, brain, cardiovascular system, and metabolism.
And yet deficiency is still incredibly common.
Here’s what I see in practice: people rely on sun exposure, assume they’re fine, then their bloodwork says otherwise. It’s not your fault. Vitamin D production depends on a long list of variables:
- latitude + season (UVB is limited in winter at higher latitudes)
- time of day (midday matters most)
- skin tone, age, clothing coverage
- sunscreen (very effective at blocking UVB)
- genetics (some people process or respond to vitamin D differently)
That’s why the simplest, most reliable approach is a practical one:
1. Test properly (25-hydroxy vitamin D / 25(OH)D)
2. Add PTH to interpret whether your body is compensating
3. If you supplement, don’t forget the cofactors, especially magnesium + vitamin K2
4. Retest in 8–12 weeks and adjust based on results
If you’d like support interpreting your results and building a plan, you can book a consultation with Planet Naturopath.
For more information about our services, please visit:
https://www.planetnaturopath.com/