SUNSCREENS AND SPF: THE EXPERT’S VIEW
Mr. Paul Banwell is one of the UK’s leading plastic surgeons and a world-wide authority on skin cancer and skin health. He has a specialist interest in skin care, skin health and skin cancer and was the Founder and Head of the Melanoma and Skin Cancer Unit (MASCU) in East Grinstead. He now the Director of the Banwell Clinic in East Grinstead and Harley Street London and works for the Kent Community Dermatology Service
In answer to many questions on sun awareness and sunscreens, Mr Banwell provides an easy-to-understand hot-list of answers to the most commonly asked sun protection questions....
Q: What is the difference between Chemical and Physical (Mineral) Sunscreens?
There are two main types of sun cream – chemical and mineral (which may also be known as physical). The main difference is that chemical sunscreen products contain UV filtering ingredients that take time to be absorbed by the skin – hence people using the 20 minute rule before sun exposure. By contrast, mineral sunscreens contain inert UV protective ingredients such as zinc and titanium oxide and form a protective barrier on top of the skin, and these have an immediate effect.
What is more, some people who suffer allergies or sensitivities to chemical UV filters find that mineral SPFs do not irritate their skin. Zinc is also anti-inflammatory and does not block pores. The downside of mineral SPFs is that they used to be very thick and white but newer preparations are more ‘cosmetically elegant’ and become transparent when applied ( these are the so-called mincronised or nanodised preparations) – they are even available in spray format too.
Q: What are the Key Advantages & Disadvantages of Both Types of Sunscreen?
Advantages of Chemical Sunscreens:
Good protection from both UVA and UVB rays (not all sunscreens offer this, so do check). The most popular UVA and UVB filters include benzophenone, avobezone, parsol and cinnamates.
Disadvantages:
The chemical filters parsol and cinnamates may not be good for sensitive skins, but the main irritant - the UVB-filtering ingredient PABA (para-aminobenzoic acid) - has been phased out of most sunscreens.
Advantages of Mineral Sunscreens:
Zinc Oxide or Titanium based sunscreens contain excellent physical protection (they are not absorbed). They are also less sensitising than chemical. Some argue that in creating a barrier between skin and sun, they are more effective than chemical filters at blocking UVA and UVB. Zinc Oxide also has anti-inflammatory healing properties.
Disadvantages:
Often thicker and more occlusive than chemical sunscreens. This has long been their biggest drawback, but the newer mineral sunscreens are much more refined and cosmetically elegant – this is whole concept of nanodised and micronised formulations as well as more recent concepts of superfluid-like products .
Q: Can Chemical Sunscreen Cause Cancer?
Not to our knowledge although some ingredients in chemical sunscreens may cause reactions in the skin. PABA has been withdrawn but this is an irritant as opposed a carcinogenic.
Q: What Determines the Price of Sunscreen?
The cost of sunscreen mainly relates to the complexity of the ingredients and the extensive tests and research that go into making the cream feel and smell good. Cosmetic chemists will spend months and years tinkering with optimal compound preparations to benefit the consumer. Marketing costs may also play a significant role.
Advanced sunscreens may also utilise patented technology which also comes at a price.
Q: What is the Difference Between UVA and UVB Rays?
UV is a form of radiation emitted from the sun, and it is invisible to the naked eye. It is usually divided into 3 groups, A, B & C.
UVA is linked to cell ageing and long term skin damage and is implicated in some skin cancers, but thought not to be as harmful as UVB.
UVB causes sunburn and direct damage to our cell’s DNA and is thought to cause most types of skin cancer.
UVC does not penetrate our atmosphere much and is low risk.
However, the concept of the ‘Solar Constant’ has become more relevant as we know this comprises UVA, UVB but also Infra Red radiation and Visible light. These also cause skin damage which predisposes to skin cancer
Whilst short term exposure to UV causes sunburn and tanning, long term leads to loss of skin elasticity, severe wrinkling, pigmentation and pre-cancerous conditions such as solar keratosis as well as skin cancer.
Q: What is the UV Index?
The UV index measures the amount of UV reaching the earth around mid-day, and is a relative scale from where 1 is low and 10 is extreme. It gives a more objective measure than 'time to burn'.
Q: How Should the UV Index Influence our Choice and Use of Sunscreen in Different Countries?
The UV index will vary from country to country and the intensity of penetration means taking greater care to protect yourself in hotter countries such as Australia, the Caribbean and southern Europe.
However, the choice of sunscreen should be the same…..more regular application may be required though to avoid burning.
Remember – burning episodes (and sunbed use) are the most sensitive future predictive factor of skin cancer formation. Avoid burning at all costs!
Q: What else should we know about Sun Protection?
It is possible that the increased use of sun creams may give people a false sense of security which may encourage people to go into the sun more and, as a result, cause an increase in the risk of developing skin cancers. Sunscreens only partially protect your skin; therefore using sun cream does not mean that you can sunbathe for long periods without harm. Australia leads the way in sun protection. Zinc oxide found in mineral sunscreens provides the best sun protection but, when applied, its appearance is white (as commonly seen with professional cricketers). This is not very ‘cosmetically elegant’ so scientists have recently patented revolutionary technology to make zinc oxide become transparent, which is more acceptable to consumers. This concept has been taken further with the development of Superfluid technology.
Niacinamide serum (vitamin B3) is another exciting breakthrough and is now available to patients in the UK. Research has shown it has significant anti-skin cancer properties, as well as reducing skin damage and areas of pigmentation. Other novel immuneprotectants include Resveratrol and there also are some exciting other innovations in photoprotection derived from extremophile plants and marine life.
We also know that Vitamin D help guard against skin cancer and is a powerful immune protectant too so supplementation with daily Vitamin D3 confers benefits in combination with Sunscreens. ARTIS London offers a powerful formulation of Vitamin D3 called Photo Immune Complex.
Q. Skin cancer in Men is more common – why?
The stats promoted by all associations gobally - by age 50, men are also more likely than women to develop melanoma. This number jumps by age 65, making men 2 times as likely as women of the same age to get melanoma. By age 80, men are 3 times more likely than women in that age group to develop melanoma.
Men are less likely to protect their skin from the sun so it is an attitude (Psychological Health 2019) and educational issue but we also know that men tend to apply less sunscreen than women and also less often. Behavioural habits need to be modified to impact on this. Furthermore. Women’s cosmetics are often formulated with synthetic melanins (which act as powerful chromophores), self-tanners contain chromophores too and many moisturisers also contain SPF – these all further minimise the effects of UV radiation.
It is also believed that another major cause of skin cancer being more common in men may lie in the physiology of men’s skin. We know that men’s skin differs from women’s skin biochemically and structurally. For instance, structurally men have thicker skin and less fat with more collagen and elastin – the fibres that give the skin firmness. Biochemically a man’s skin is less acidic than a woman’s and there is evidence that the difference in these intrinsic enzymatic processes may also contribute to the predisposition to skin cancer. Another study conducted in Holland found that men’s skin has a more intense phototoxic response to ultraviolet radiation compared to women’s skin and is less good at DNA repair compared to female skins.
Mr Paul Banwell is available for private consultations on skin care, skin health, skin cancer checks, anti-ageing treatments, regenerative medicine and cosmetic surgery. He consults privately in East Grinstead, Tunbridge Wells and London. Please call 01342 330302 or see www.paulebanwell.com.