Sun protection and Vitamin D after melanoma
Date August 2015
Humans generally make most of their vitamin D when their skin is exposed to the sun. This advice is written for melanoma patients in the UK in particular because what we say about vitamin D depends on what the weather is like and whether foods such as orange juice are fortified. In the UK few foods are fortified and the weather is not particularly sunny so that low levels of vitamin D are a particular problem. Similar conditions may apply to other countries in temperate regions of the world but this information is developed based upon research in the UK.
Once you have been diagnosed with melanoma, healthcare teams usually advise you to avoid too much intense sun exposure. This is for two reasons:
- It may reduce the risk of developing another melanoma, which is important as 1 in 10 melanoma patients develop other primary melanomas in time.
- There are theories that sunburn may stop your immune system working as well as it should.
Yet, we know sun exposure is generally important to health because it allows your body to make vitamin D, which is crucial for bone and muscle health. Older people taking vitamin D for example are less likely to fall.
There is some evidence that vitamin D may also be important for your health after a diagnosis of melanoma. This is very new information and we need the results from further studies before we can be sure it is right. Even though we have not proved that vitamin D has any effect on melanoma, because vitamin D is necessary for many other aspects of your health, we would say that having enough vitamin D is important.
If you were to significantly reduce the amount of sun exposure you get now, then this may reduce your chance of another melanoma but could damage your health by reducing your vitamin D levels.
So what is our advice to you?
The best advice we can give you is to avoid too much sun exposure whilst avoiding vitamin D insufficiency and below we explain how.
Most importantly, avoid sunburn
Secondly, when the UV index is at or above three:
- Avoid staying out in the sun for long periods.
- Avoid exposing unprotected skin to the sun between 10am and 2pm in particular.
- Use sun protection such as factor 30 SPF sunscreen with four or five stars UVA protection.
- Use appropriate clothing to protect your skin where possible.
The UV index will vary depending on where you are in the world, the season and the time of day. For example, in Australia people may need to practice sun protection for most of the year. For people who live in Northern England the length of time will be shorter.
When UV levels are high, adequate vitamin D is quickly created in the skin so prolonged exposure is not necessary. However in the UK, in practice ,most people do not have sufficient sun exposure to make enough vitamin D much of the year round.
Thirdly, avoid becoming deficient in vitamin D
Whilst avoiding low levels of vitamin D is important, some scientists have concerns that melanoma patients should also avoid high levels of vitamin D in the blood. Research is underway to find the right dose. In the meantime the NICE Clinical Melanoma Guideline suggested that newly diagnosed melanoma patients should have their blood levels tested and should take supplements as advised by their medical teams if their levels are judged to be low http://www.nice.org.uk/guidance/ng14.
Most melanoma patients in the UK will need 400 (10µg) of vitamin D3 in the very long term, which can be bought from the chemist or the health food store. We would advise vitamin D3 without added calcium. Some patients who have very low levels at diagnosis and others eg patients who are overweight may need the higher dose of 800IU (20µg) per day as vitamin D is a fat soluble hormone. If you have not had your blood levels measured in the hospital then taking 400IU per day is reasonable and if in doubt discuss with your doctor. They may wish to measure the current level in your blood. The aim is to have a level of between 60 nmol/L in winter and 85 nmol/L in the summer.
- If you have kidney disease, a high calcium level, kidney stones or heart disease speak to your doctor before taking supplements.
- Talk things through with your healthcare professional.
How much vitamin D do other agencies say is enough?
The Institute of Medicine in the USA has recently recommended 600 IU per day for most adults.
The UK Scientific Advisory Committee on Nutrition (SACN) published a guideline in 2016 which has suggested that most UK residents need to take 400IU per day because of the relatively low level of sunshine in the UK. The guideline is available via the SACN website.
Advice for family members
When someone has had a melanoma, then because family members tend to have the same skin type as their relative who has had a melanoma, it is sensible to advise them also to avoid sunburn and intense sun exposure as described above. Advice about avoiding vitamin D deficiency would also then apply to them and the advice of the SACN is especially useful for them. For children advice about supplementation should be sought from the GP, health visitor or pharmacist.
For adult blood relatives of melanoma patients:-
- We think that the best advice is to take vitamin D3 tablets if you are avoiding excessive sun exposure which can be bought from health food shops or on-line. We would recommend taking 400IU (10µg) daily for most people. The SACN recommended 400IU per day as a total dose so if you are eating supplemented foods such as cereals with added vitamin D then you will not need 400IU as a tablet every day
- Or family members can eat foods that are naturally rich in vitamin D (such as fatty fish and eggs) or that have been fortified with vitamin D (such as some yoghurts and cereals). If they eat reasonable quantities of these foods they may not need to take supplements every day. A portion of cooked wild salmon (3 ounces/85 grams) for example may contain 447 IU of vitamin D.* Generally speaking however people find it hard to eat enough vitamin D in food to maintain normal levels in temperate climates such as the UK and most people find it easier to take the supplements. This is especially true for vegetarians for whom wild mushrooms, eggs and fortified foods such as fortified soya are pretty much the only options.