Sunlight "D"ilemma ... Part 2

[Doc Alan]

Last March ( when the UK had unseasonably sunny weather ) I posted " Sunlight "D"ilemma " on the advantages and disadvantages of sun exposure.


This week Cancer Research UK issued a press release pointing out that death rates from malignant melanoma – the most serious kind of skin cancer – are much higher in men than women, despite similar numbers being diagnosed each year.


( Malignant ) melanoma is a rare type of cancer involving melanocytes ( cells producing melanin pigment ) usually – but not always – in the skin. As with other cancers, the cells undergo purposeless proliferation, may invade surrounding tissues and may spread through lymph system or bloodstream to lymph nodes or other organs.


The main risk factors are excessive exposure to ultraviolet ( UV ) light from sunlight or artificial sources ( sunbeds ) ; pale skin colour ; large number of moles ; and family / personal history of the cancer.


The first sign is often the appearance of a new pigmented area ( " mole " ) or changed appearance of a pre-existing mole.


This is the ABCDE checklist :-
• Asymmetrical – irregular shape
• Border notched or ragged ; may Bleed
• Colours – mixed, usually different shades of brown
• Diameter usually larger than 6mm / ¼ inch
• Evolution and Enlargement – change of appearance with ulceration over time.



Men and women tend to develop melanomas in different places – back and chest for men ; arms and legs for women. Women are more cosmetically aware and tend to visit their doctor sooner than men. There may also be immune factors, men’s immune defences possibly being less good in fighting this cancer.


Melanoma can occur at any age, but it is one of the few cancers which is relatively common in young adults.


It is usually – and best – treated by surgical removal, the earlier the better. Although increasing in frequency in the UK, so also has the chance of survival improved, especially in women. At least 8 / 10 people diagnosed with melanoma survive 10 years.


The outlook for advanced melanoma is not good. However, we know more about the " biology " of this cancer – over half the cases have a faulty gene ( " BRAF " ). This means that instead of chemotherapy ( drugs not just killing melanoma cells but also many normal rapidly dividing cells ), there are now drugs which " target " this gene, with at least partial response. Immunotherapy ( strengthening immune responses ) has also been tried for many years.



The highest frequency of this cancer is in Australia, USA, Scandinavia, as well as UK. It is FAR less common in black populations, the Philippines and elsewhere in Asia. Despite this, local and " health tourist " foreign patients may be treated in such hospitals as " The Medical City " ( Pasig City ), " Asian Hospital and Medical Center " ( Multinlupa ), " Makati Medical Center ", and " St. Luke’s Medical Center " ( Quezon City ).



http://filipinaroses.com/showthread....t=sun+exposure



http://www.cancerresearchuk.org/canc...SiteId=funding

[Dedworth]

Very interesting Doc and timely if we have a scorcher this upcoming weekend

[bigmarco]

Interesting post Doc and much appreciated by this pale skin.
Surprised to see that the death rates are highest amongst males.

[jake]

Very good information

It has been a longtime since i lived in the UK but i still remember how peoples mood seemed to change for the better when the sun was shining.

Doc, you seem to always have a healthy looking tan. What sunscreen do you use and why?

[gWaPito]

Very good information

It has been a longtime since i lived in the UK but i still remember how peoples mood seemed to change for the better when the sun was shining.

Doc, you seem to always have a healthy looking tan. What sunscreen do you use and why?

Certainly does I just bought my mother an SAD lamp for her 82nd birthday...we're hoping it will help take the rough edges off her tongue

[Doc Alan]

Thank you Ded, Bigmarco, and Jake !


Here in the UK I use moisturising sunscreen with SPF 15 and UVA protection. In the tropics or southern Europe, SPF 50 with high UVA protection. I’m lucky in that my skin tans easily and I don’t burn in sunlight, but as I like outdoors activities I do try always to use sunscreen.


Here’s why :-


• Solar or artificial ultraviolet irradiation can harm the skin. It’s responsible for various skin disorders, and some drugs may cause increased skin sensitivity to UV light. These conditions (as well as sunburn) may occur after relatively short periods of exposure.


• The effects of exposure over longer periods include ageing changes and more importantly risk of skin cancer, especially in fair / white skin.


• Melanoma is the most serious, but thankfully the least common skin cancer, and it does not directly result from sun exposure, but depends more on accumulated exposure over years.


• By far the most common skin cancer is " rodent ulcer " ( basal cell carcinoma ) which does however usually remain localised to the sun-exposed site of origin. Squamous cancer is the next commonest, also directly the result of sun exposure, and may spread elsewhere. These tend to affect older people.


• Solar UV radiation is around 200–400 nm in wavelength. Medium wavelengths (290–320 nm, or UVB) cause sunburn. Long wavelengths (320–400 nm, or UVA) are responsible for many photosensitivity reactions and other skin diseases. Both UVA and UVB cause long-term damage and changes responsible for skin cancer and ageing.


• Sunscreen preparations contain substances that protect the skin against UVA and UVB radiation, but they are no substitute for covering the skin and avoiding sunlight. The sun protection factor (SPF, usually indicated in the preparation title) provides guidance on the degree of protection offered against UVB. It indicates the multiples of protection provided against burning, compared with unprotected skin. So a SPF of 15 should allow someone to remain 15 times longer in the sun without burning. Often, users don’t apply sufficient sunscreen product and the protection is lower than expected.


• Some manufacturers use a ( less precise ) star rating system to indicate the protection against UVA relative to protection against UVB for sunscreen products.


• Sunscreen preparations MAY cause allergic reactions, hard to predict – try a different one !


• They should be applied thickly and frequently ( 2 hourly ).
As a guide ( UK spring – autumn ):-


1. Fair / sensitive, facial and children’s skin – start with SPF 50, then reduce to 25(+) in UK ; always 50 in Philippines.

2. “ Normal “ skin – start with 25, then 15 in UK ; 25-50 then 15 in Philippines.

3. Dark skin – start with 25, then 15 in UK ; 25-50 then 15 in Philippines.


On a positive note :-

• Even if you’re worried about a skin lesion which may be new, increasing in size, and pigmented, by all means see a doctor who may recommend removal as a precaution. Every such lesion is routinely sent to a pathologist for microscopic examination. Of the very many such lesions excised, only a small proportion are cancer ( most commonly " rodent ulcer " ).


• Even among the pigmented lesions removed, by far the majority are benign ( non cancerous ) ; malignant melanoma is relatively rare even in the UK.

[Rosie1958]

Thanks for the information Doc Alan. We have posters displayed at work showing photos of different types of skin lesions and moles which I find very helpful. Having lived abroad as a child/ teenager in several hot countries, I am aware of the dangers and do regularly check for changes in skin pigment, etc.

Just before I went to Mexico a couple of years ago, I became aware of a change in a small mole that I'd had on my forehead since birth, I saw a consultant, he thought it wasn't serious but made arrangements to remove it as a precaution after I came back from holiday. Whilst on holiday I wore a large straw hat to protect my head and face from the strong sunrays and it was the best thing I could have done. The hat kept rubbing on the mole, made it bleed, scabbed over and eventually it came off so I didn't need surgery. I was very lucky and don't even have a mark to show where it had been but wouldn't hesitate to seek advice again if I spotted anything else that looked suspicious.

[raynaputi]

Good post again Doc!

[Doc Alan]

Thank you Rosie for your interesting post, and Rayna for your support as always .

[jake]

Thank you Doc for another informative reply.

You are very lucky that your skin tans so easily. Even though i am not red headed the ginger gene is kicking around in the family

Last year whilst visiting my mum i was given this book by a friend.

http://www.amazon.co.uk/The-Scots-A-.../dp/1841589411

Fascinating read IMO

[Doc Alan]

There’s been recent interest in the Forum on exercise and the skin. Lately the media have reported Cancer Research UK statistics - either unfavourably ( “ Skin cancer rates surge since the 1970s “ ) or favourably ( “ 9 in 10 people survive the disease “ ).


Members should be aware, rather than worrying too much .



Most skin cancers are caused by ultraviolet ( UV ) rays, either from sunlight and/or sunbeds. So-called " non-melanoma skin cancers " are by far the commonest. They occur in skin exposed to UV rays, and the risk depends on total lifetime exposure, especially in fair-skinned people. Most are " rodent ulcers " / basal cell carcinomas ; many of the rest are " squamous cell carcinomas ". Unlike other cancers, these usually grow slowly and rarely spread. A persisting skin ulcer or nodule, especially if it bleeds, should be reason to visit a doctor. Proof of the diagnosis would require removal and microscopic examination by a specialist.



There is FAR more information on melanoma, although it is much less common ( in the world, perhaps 130,000 cases / year ; compared to possibly 2 -3 million / year other skin cancers, the numbers not even being known accurately ). Here intermittent intense UV exposure ( " Mediterranean / tropical " sun ) are important - and melanomas don’t necessarily occur on the most exposed skin sites. All types are thought to be increasing in frequency. They vary from country to country, being relatively frequent in the UK and uncommon in the Philippines.



Artificial tanning sunbeds increase the risk of skin cancers, and as the risks are greater for young people, they’re illegal under the age of 18 in the UK.



In the Philippines, there is much more interest in skin - whitening / lightening products. These don’t, so far as I am aware, cause cancer, but they can be harmful. They may contain steroids and/or hydroquinone which can cause irritation, thinning and permanent bleaching ; and ( especially those from China ) mercury which could also cause kidney damage. Take local expert advice from pharmacist or doctor. ( http://www.philstar.com/metro/2013/1...ening-products
; http://www.nhs.uk/Livewell/skin/Page...ightening.aspx
).


No general screening programme exists in the UK for skin cancers. An awareness of risks, and noting new skin lesions or changes in old lesions ( increase in size, ulceration, change in colour, bleeding ) are important for early diagnosis and cure - with a minimum of worry ! Enjoy being out in sunny weather … in moderation and with skin protection .


There’s more information in my previous posts / links on this thread, and also the Cancer Research UK website : -

http://www.cancerresearchuk.org/canc...ts/types/skin/

[Doc Alan]

By chance during the hottest week of the year so far, new government advice has been issued on vitamin D, which apply especially in the UK winter. It’s been widely reported in the media.


Unlike other vitamins, we don’t need to get vitamin D from food. It is made in the skin by the action of UVB rays in sunlight. Too much sun, of course, damages the skin. Most of the UK population doesn’t have enough sunlight for half the year ( October to April ) to make enough of this vitamin.


Foods containing vitamin D include oily fish and those with added vitamin D ( " fortified " ).


Vitamin D is important for strong and healthy bones ( though helping absorption of calcium and phosphorus in our diet ). It also seems to be important for muscles and general health.


Growing children, pregnant and breast-feeding women need extra vitamin D.


People who get very little sunlight on their skin are at risk of vitamin D deficiency. Even in the UK summer and the Philippines this may be from staying indoors a lot ; covering up and strict sunscreen use when outdoors ; and those with darker skin. Other factors, such as thinner skin in elderly people and medical conditions, may mean enough vitamin D can’t be made in the skin.


While severe vitamin D deficiency may cause weak and distorted bones ( rickets in children ; osteomalacia in adults ) ; mild deficiency may simply cause general tiredness, aches and pains ( for which there are many other causes ).



Vitamin D supplements are widely available from supermarkets and pharmacists both in the UK and the Philippines.


The UK government advice is just that. My purpose, as always, is to inform ( not advise ). Personally I have read the updated advice with interest, and don’t consider I need to take regular vitamin D supplements ( diet and sun exposure sufficient ). However, it may be worthwhile reading more about the topic, the best links in my opinion being here :- 1, 2, and 3.

[grahamw48]

I take a cod liver oil capsule.. with added vit D, every day.

[Michael Parnham]

I take a cod liver oil capsule.. with added vit D, every day.

So do I, been taking them since I weaned myself off cod liver oil from a spoon, also thank you Alan for another useful informative post.

[Steve.r]

Thanks Alan.

But my question is, what parts of the body most absorb vit D from sunlight? Arms, legs, torso etc? How much exposure is enough when we are told that too much sun will cause melanoma?

[Doc Alan]

But my question is, what parts of the body most absorb vit D from sunlight? Arms, legs, torso etc? How much exposure is enough when we are told that too much sun will cause melanoma?

Any skin directly exposed to sunlight may synthesise vitamin D. The number of minutes varies by the time of year, skin colour, age, and where you are. For a fair-skinned person, it’s estimated that ~ 25 minutes of sunlight on face and forearms around the middle of the day 2-3 times a week would be sufficient, in the summer months in the UK. In tropical latitudes it would be less time. For dark-skinned ( and elderly ) it would be longer.


However, dermatologists tend not to recommend deliberate sun exposure as a " safe " means of getting vitamin D.


The "D"ilemma pitches vitamin D against " safe skin ". At the very least, burning ( redness, or worse ) should be avoided. Sunburn may cause DNA damage in skin cells ( with risk of change to cancer ).


It’s not only malignant melanoma which may result from excessive sun ( and sunbed ) exposure. Other skin cancers are also increased in frequency ( " squamous carcinoma " and " basal cell carcinoma / rodent ulcer " ). Although melanoma is the most serious ( while most can be successfully treated ), these other cancers are more common.


There is a further caution - taking vitamin D in higher than recommended doses can raise calcium levels in the blood - with various effects, such as passing much urine, nausea, vomiting and headaches.


More information is available on links 1,2, and 3 in my previous post #12. There’s now concern about rickets and osteomalacia in immigrants and ethnic risk groups, especially children ( see link ).

[Steve.r]

Thanks again Alan. Good info as normal

[Arthur Little]

Thanks again Alan. Good info as normal

... EXCELLENT as always!

[Michael Parnham]

... EXCELLENT as always!

Ditto

[jonnijon]

And to think of the hours we spent as kids on the beach, no such thing as sun cream, or if there was we could not afford it. Would be red raw at the end of the day Ma would slap on the Calamine and next day we would be back on the beach for more.

[Doc Alan]

Thank you Graham, Michael, Steve.r, Jonnijon, and Arthur for your responses and kind comments

Despite all the serious health messages, there is, for most people, especially in the UK, a " feel good factor " when we have a sunny day following cloud and rain .

As with other enjoyable activities, moderation and common sense would seem wise