Vitamin D in adults diagnosed with melanoma

Publication: 02/08/2021  
Next review: 02/08/2024  
Clinical Guideline
ID: 7094 
Approved By: Trust Clinical Guidelines Group 
Copyright© Leeds Teaching Hospitals NHS Trust 2021  


This Clinical Guideline is intended for use by healthcare professionals within Leeds unless otherwise stated.
For healthcare professionals in other trusts, please ensure that you consult relevant local and national guidance.


Aim of guideline

This guideline is intended to be specifically used to aid both primary and secondary care clinicians in the measurement and management of vitamin D levels for patients diagnosed with melanoma.

For advice on the management of adults without melanoma, but with Vitamin D deficiency or insufficiency in primary and secondary care link, on Leeds Health Pathways.

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Research has shown that melanoma patients 3 or more years after diagnosis, if untreated, have low levels of Vitamin D in the UK 1. This is likely a result of sun avoidance in order to reduce the risk of another melanoma. In addition, patients with lower levels of vitamin D at diagnosis have both thicker tumours and poorer prognoses1. NICE guidelines for Melanoma (2015) state that all patients with melanoma should have their Vitamin D levels measured at diagnosis 2. It is also recommended that people with suboptimal Vitamin D levels should be given advice on Vitamin D Supplementation and monitoring in line with local polices.
There are theoretical concerns about taking too much Vitamin A alongside Vitamin D, as found in cod liver oil tablets. Higher levels of Vitamin A might counteract the potentially beneficial effects of Vitamin D on health. Study results to date do not support the view that higher levels of vitamin A have any adverse effect on outcome, but were unable to exclude a small effect3. Hence, our current recommendation is to use supplements that contain Vitamin D3 only.

There are theoretical concerns that high doses of vitamin D might be harmful by suppressing the immune system, and therefore levels in excess of 90 nmol/L should be avoided (although levels do climb over this after sunny holidays and then settle).44 We therefore recommend avoiding rapid rises and falls in Vitamin D levels in melanoma patients.

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Definition of acceptable range for the Vitamin D level in patients diagnosed with melanoma

An acceptable range for melanoma patients in Leeds is considered >50nmol/l and <90nmol/l.

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Step-by-step guide to measuring, treating and monitoring Vitamin D levels (see appendix for decision aid tables)

  1. Measure 25-OH Vitamin D3 level in all newly diagnosed melanoma patients at baseline (first outpatient appointment for results or within the first 3 months of diagnosis). Avoid checking if patient has just come back from sunny holiday in the last month as this will falsely elevate the result
  2. Give patients the Leeds Sun protection and Vitamin D information Leaflet which contain information on what foods contain Vitamin D.
    Sun Protection & Vitamin D Leaflet
  3. Ask the patient if they take:
    • A Vitamin D supplement (and dose)
    • A multivitamin containing Vitamin D
    • Cod liver oil
    • Any Medication containing Vitamin D or
  4. Document any of these supplements in the clinical letter and notes. If the patient is unsure of details, ask them to bring the details or the packaging to their next outpatient appointment or ring the clinical nurse specialist team with the details to be passed on to the doctor
  5. On receipt of the 25-OH Vitamin D3 level result, write to the patient and copy in their General Practitioner. Supplementation is dosed according to international units (IU). Vitamin D supplements can be bought over-the-counter from pharmacies and health food stores and we should encourage patients to do so. Patients should be advised to take the Vitamin D alone, rather than as a multivitamin or cod liver oil. Supplementation is without added calcium, unless needed for other co-morbidities. Dosing can be the same at any time of the year. The recommended supplementation dose varies according to the degree of Vitamin D deficiency in melanoma patients;
    1. If 25-OH Vitamin D3 levels <25 nmol/L, recommend 800 International Units (IU) per day (20 micrograms)
    2. If 25-OH Vitamin D3 levels >25 nmol/L but <50 nmol/L, recommend 400 International Units (IU) per day (10 micrograms)
    3. If 25-OH Vitamin D3 levels >50 or <90 nmol/L patients do not need to take supplements or they can continue on current supplementation
    4. If 25-OH Vitamin D3 levels > 90 patients should stop supplements
  6. Vitamin D levels should be repeated 6 months after the baseline assessment;
    1. If patient was taking 800 International Units (IU) and level has now improved to >25nmol/L, recommend to reduce to 400 International Units (IU) daily. If the level is still <25nmol/L then consider doubling dose to 1600 International Units (IU). Check the patient is definitely compliant with taking the supplementation. Patients who are overweight may require larger doses
    2. If the patient was taking 400 International Units IU and the level remains >25nmol/L but <50nmol/L without much change, recommend to double the dose to 800 International Units (IU)
    3. If level is in the recommended range of >50-90nmol / L then continue on 400 International Units (IU)
    4. If level >90nmol/L, recommend the patient stops taking Vitamin D supplement
  7. Repeat the Vitamin D again in a further 6 months if the level has not reached the recommended range of >50-90nmol/l.

If the Vitamin D has reached the recommended range of >50-90nmol/L, the level does not need to be rechecked

Patients should be advised to stop taking Vitamin D supplements when going on sunny holidays.

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Table1: Decision aid table for dosing of vitamin D supplementation for initial blood levels of Vitamin D at diagnosis

level of Vitamin D at diagnosis (nmol/L)

Dosage on receipt of test result of initial test (Units)



>25 - 50


>50 - 90

patients do not need to take supplements or they can continue on current supplementation if already taking


Patients should stop taking supplements if already taking

  • Levels should be repeat at 6 months after baseline assessment

Table 2: Decision aid table for dosing of vitamin D supplementation for repeat blood levels 6 months after initial test

Level of vitamin D at 6 months after baseline assessment (nmol/L)

If patient taking 800 Units daily

If patient taking 400 Units daily

If patient not taking a supplement (baseline was within acceptable range)


consider doubling to 1600 Units

double dose to 800 Units

Start 800 Units as per table 1

>25 - 50

reduce dose to 400Units

double dose to 800 Units

Start 400 Units as per table 1

>50 - 90

reduce dose to 400 Units

continue 400 Units and does not need further vitamin D checks unless clinical situation alters

Patient does not require supplementation and does not need further vitamin D checks, unless clinical situation alters


stop vitamin D supplement

stop vitamin D supplement

  • Levels should be repeated in 6 months for any dose changes
  • If level is not within recommended range after 12 months treatment, please discuss with the Melanoma Dermatology Consultant Team (Dr Angana Mitra, Dr Andy Muinonen-Martin, Dr Elizabeth Blakeway)


Record: 7094
Clinical condition:
Target patient group:
Target professional group(s): Pharmacists
Primary Care Doctors
Secondary Care Doctors
Adapted from:

Evidence base


  1. Newton-Bishop J, Beswick S, Randerson-Moor J, Chang Y, Affleck P, Elliott F et al. Serum 25-Hydroxyvitamin D3 Levels Are Associated With Breslow Thickness at Presentation and Survival From Melanoma. Journal of Clinical Oncology. 2009;27(32):5439-5444.
  3. Field S, Newton-Bishop J. Melanoma and vitamin D. Molecular Oncology. 2011;5(2):197-214
  4. Field S, Davies J, Bishop D, Newton-Bishop J. Vitamin D and melanoma. Dermato-Endocrinology. 2013;5(1):121-129.

Approved By

Trust Clinical Guidelines Group

Document history

LHP version 1.0

Related information

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