Skip to content
The Skin Doctor

Patients who must avoid the sun — because of a skin-cancer history, photosensitivity or immunosuppression — can still maintain healthy vitamin D levels. This article explains how to do so safely through diet and supplementation, the blood levels to aim for, why sun avoidance need not mean deficiency, and what the evidence does and does not say about vitamin D and melanoma.

Prevention

Optimising vitamin D and nutrition for sun-avoidant and high-risk patients

Patients who must avoid the sun — because of a skin-cancer history, photosensitivity or immunosuppression — can still maintain healthy vitamin D levels. This article explains how to do so safely through diet and supplementation, the blood levels to aim for, why sun avoidance need not mean deficiency, and what the evidence does and does not say about vitamin D and melanoma.

Portrait of Dr Christopher Irwin

By Dr Christopher Irwin, MBChB, FRACGP, MMed (Skin Cancer), FACAM, MSCCA

Last reviewed 2026-06-06 · 6 min read · Editorial policy

Quick summary

If you must minimise sun exposure — because of a skin-cancer history, photosensitivity or immunosuppression — you can still keep your vitamin D healthy without deliberate UV exposure. The reliable approach is diet + a supplement guided by a blood test, aiming for the generally adequate level of around 50 nmol/L or above. (1) Regular sunscreen use has not been shown to cause deficiency. (2) Sun protection and healthy vitamin D can coexist — it just needs a deliberate plan.

Patients who must minimise sun exposure face a genuine question: how do you keep vitamin D healthy when the simplest source is the very thing you need to avoid? The good news is that this is a well-solved problem — with diet, supplementation and monitoring, sun-avoidant patients can maintain entirely healthy levels without any deliberate UV exposure.

Why vitamin D matters

Vitamin D is essential for strong bones, calcium balance, immune function and general health; severe deficiency causes rickets in children and osteomalacia (soft bones) in adults. (1) For skin-cancer patients there is particular interest in melanoma: some observational studies associate higher vitamin D levels with thinner melanomas and better outcomes. This is an association — it does not prove that supplements change outcomes, so the aim is healthy (not high) levels as part of a broader plan, not megadosing.

How sun-avoidant patients maintain vitamin D

The strategy rests on three pillars.

1. Diet

Very few foods naturally contain meaningful vitamin D. The best sources are oily fish (salmon, mackerel, sardines), egg yolks, and fortified foods such as some margarines, milks and cereals. For most sun-avoidant patients, diet alone is insufficient.

2. Supplementation

For most sun-avoidant patients, a daily vitamin D supplement is the most reliable way to maintain healthy levels. The dose is individualised to your blood level.

3. Testing and monitoring

A simple 25-hydroxyvitamin D blood test tells us your level. We use it to decide whether you need a supplement and at what dose, then re-check periodically. Australian and New Zealand guidance regards around 50 nmol/L or above (measured at the end of winter) as adequate for the general population; a different target may be chosen in specific clinical situations. (1)

Does sunscreen cause deficiency?

In real-world use, no. Regular sunscreen use has not been shown to cause vitamin D deficiency — no sunscreen blocks 100% of UV, and incidental everyday exposure continues. (2) Sun protection and vitamin D sufficiency genuinely coexist.

The bottom line

Sun-avoidance and healthy vitamin D are not mutually exclusive — it simply requires a deliberate plan rather than relying on incidental sun exposure.

Frequently asked questions

  • Can I get enough vitamin D through diet alone?
    It is difficult. Very few foods naturally contain meaningful vitamin D (oily fish, egg yolk, some fortified products). For people who avoid the sun for medical reasons, a supplement guided by a blood test is usually the most reliable route.
  • What blood level of vitamin D should I aim for?
    Australian and New Zealand guidance regards roughly 50 nmol/L or above (measured at the end of winter) as adequate for the general population. Your doctor may choose a different target in specific situations. The right target and dose should be individualised and confirmed with a blood test.
  • Will sunscreen make me vitamin D deficient?
    In real-world use, no. Regular sunscreen use has not been shown to cause vitamin D deficiency, because no sunscreen blocks all UV and incidental everyday exposure continues. Sun protection and healthy vitamin D levels can coexist.
  • Does vitamin D affect melanoma outcomes?
    Observational research links higher vitamin D levels with thinner melanomas and better outcomes, but this is an association — it does not prove that taking supplements changes melanoma outcomes. We aim for healthy (not high) levels and treat vitamin D as one part of a broader plan.

References

  1. Nowson CA, McGrath JJ, Ebeling PR, et al. Vitamin D and health in adults in Australia and New Zealand: a position statement. Med J Aust. 2012;196(11):686-687.
  2. Cancer Council Australia — Position statement: Risks and benefits of sun exposure (vitamin D and sun protection).

Related

Portrait of Dr Christopher Irwin

By Dr Christopher Irwin, MBChB, FRACGP, MMed (Skin Cancer), FACAM, MSCCA

Last reviewed 2026-06-06 · Editorial policy