Our sun has been shining on Earth for the last 6 billion years. It wasn't until around 30 years ago that we actively started paying attention to how it was affecting us. In 1978, the US FDA announced its intention to regulate sun cream safety. The result of this was that they created the Sun Protection Factor (SPF) rating scale that was used and adhered to by all mainstream sun cream manufactures around the world from this point on.

The problem was that this rating scale was slightly flawed.

This resulted in a flurry of under-par sun creams hitting market places around the world. Most sun creams manufactured in the last 30 years failed to protect against all solar radiation that enters our skin every day. The sun creams did block a certain amount of sun rays, mainly those that cause our skin to burn, but were largely inadequate in offering full spectrum protection – especially against “photo-aging” (the wrinkling effect that occurs when skin is exposed to sun light).

What is ultraviolet light and what is the difference between UV-A and UV-B?

Ultraviolet light is a specific form of ionising radiation coming from the sun that can severely injure and in some instances even kill cells in our body. This injury to the skin cells caused by ultraviolet light is commonly referred to as ‘sunburn’. There are two types of ultraviolet (UV) light – UV-A and UV-B – UV-A rays constitute up to 95% of all UV radiation hitting the surface of the Earth. As such, us humans are exposed to large amounts of UV-A  during our lifetimes. UV-A rays are less intense than UV-B, as they have a longer wave length – (or  lower frequency) than UV-B. UV-B is the type of sunlight responsible for sunburns.

However, UV-A penetrates the skin at a deeper level and has  been implicated in increasing damage to the cells that occupy that space – resulting in premature wrinkling of the skin.

What was wrong with the SPF rating scale?

Initially, SPF was expressed as the extra length of time you can stay in the sun before burning.  For example, if a fair-skinned person who would usually burn in six to seven minutes uses an SPF 15, then they can safely be exposed to the sun for 90 minutes, or 15 times longer.  Higher SPF ratings are not actually proportional, as an SPF 15 sunscreen offers 93% absorption and filtering of UV-A and UV-B sunlight, which also allows for a daily dose of Vitamin D – the “sunshine vitamin” so essential for our body can synthesize from sun exposure, compared to an SPF 30 which offers 97%.

The reason the SPF rating scale was flawed was that it didn’t take UV-A rays into account. The reason these commercial sun creams didn’t offer a broad shield layer that protected us against the whole spectrum of UV sun light, has to do with the scientific research available at the time of the creation of the SPF scale (in 1978). The research back then suggested that most of the damage associated with UV exposure was caused by UV-B and not UV-A radiation. Which isn’t entirely accurate as recent studies have found.

What Compounds to Look Out For in Commercial Sun Creams

The most common commercial sun creams on the market contain artificial chemical filters that help with UV blocking.  These products typically include a combination of the following active ingredients: oxybenzone, avobenzone, octisalate, octocrylene, homosalate and octinoxate. All fairly toxic in their own right!

Besides exposing your body to these potentially harmful chemicals like oxybenzone or octinoxate (oxybenzone may acts like oestrogen in the body, has been shown to alter sperm production in animal models and has also been associated with endometriosis in women), perhaps an even greater concern is the fact that most commercial sun creams effectively block the type of ultraviolet light needed for the body to produce vitamin D in response to exposure. As mentioned, UV-B’s are the rays responsible for vitamin D production, while UV-A’s are the ones responsible for the majority of chronic skin damage (“photo-aging”) from excessive sun exposure. Most commercial sun creams aim to block UV-B but not UV-A.

The compounds commercial manufacturers pile into their creams have been so vast that several scientific think tanks have sprung up organically around the world largely because national health authorities have been so slack in addressing this very serious health risk.

One of these non-governmental think tanks, the Environmental Work Group (EWG’s) in the US, recently released their “safe ingredient list”, advising that for sun creams to be effective and most importantly safe, they must:

  • Be free of oxybenzone and retinyl palmitate (a type of vitamin A)
  • Provide a maximum of SPF 50 (no more!)
  • Protect against both types of ultraviolet radiation (UV-A and UV-B)

Natural Sun Creams

In comparison to synthetic sun creams, natural SPF sun creams are products which use inorganic ultraviolet blockers such as titanium dioxide and zinc oxide, which create a physical barrier on the skin that works to reflect excess UV-A and UV-B rays back into the atmosphere, as opposed to your skin absorbing them.

It is for this reason that natural sun creams are considered to be milder and safer to use – especially for sensitive skin types.

Staying out of the Sun

The most effective way to preserve one’s skin health is to avoid exposure to the sun’s damaging ultraviolet rays completely. But the problem here is that we need sunshine in order to synthesise one of the most important molecules in our bodies, namely vitamin D. Although this advice may seem obvious, a surprising number of people fail to grasp its importance.

The Vitamin D conundrum

The double edged sword here is that if we don’t supplement with vitamin D, we need to be in the sun every day so that our body can manufacture vitamin D utilising the UV rays as a natural catalyst. Vitamin D is crucial for overall health and well-being; it supports our kidneys, promotes healthy teeth and bones, helps maintain an optimum immune system as well as supporting overall cardiovascular health. The goal is to find a healthy balance between obtaining adequate levels of natural sunlight to optimise vitamin D production versus protecting ourselves from the damage associated with overexposure.

The body’s bio-active form of Vitamin D, is converted from our stored supply of Vitamin D in the liver. It has a short lifespan and needs replenishing on a continual basis for healthy body function. More significantly, it has a proven role in inhibiting the conversion of healthy tissue to diseased tissue. In New Zealand studies show at least 40% of us have insufficient levels of this important vitamin, while 3 – 4% are clinically Vitamin D deficient.

Nutrients that that help minimise damage from over-exposure to UV

Astaxanthin is widely distributed throughout most tissues and organs in the body, it is highly accumulated in the epidermis, where it makes its way into all skin layers (note: most topically applied sun creams only target the outermost layers). It is also a highly potent antioxidant used by all plants to protect against harmful UV radiation. Due to the fact that it works from the inside out, it may be a very effective protection against the deeper damage by UV-A – the area missed by most commercial sun cream.

Green tea has been used for over 4000 years on this Earth, it is quite possibly the world’s oldest sun-protection “agent”. Clinical studies have revealed that green tea and green tea extract may have the ability to prevent the wrinkling effect associated with “photoaging”. It appears to work when applied on the skin as well as when taken orally.

Milk thistle contains flavonoid compounds that may protect against the DNA damage associated with over-exposure to UV. Clinical studies have revealed that these flavonoids may have potent antioxidant, anti-inflammatory, and even immune-optimising properties.

Officially approved as a healing agent for skin repair by the FDA, beta glucans also promote healthy skin and are important modulators of the immune system; as such they can help in protecting us from UV-induced skin damage.

Plants synthesise antioxidants to protect themselves from different environmental threats, bacterial, viral, fungal as well damage from excessive sunlight exposure, grape seed extract is a great source of these natural antioxidants. Furthermore, in recent clinical trials, wounds treated with grape seed extract showed better healing than those that hadn’t been treated. Grape seed extract is also a naturally anti-inflammatory agent.

Another herb that has been used for thousands of years is rosemary. Rosemary has long been known to have anti-inflammatory as well as antioxidant properties and may be beneficial in minimising long term damage from UV exposure.

So: to sun or not to sun..

.. that is the question

New Zealand happens to be located in a region on our planet that has a notoriously depleted ozone layer (the part of our atmosphere that removes excess UV radiation). Unfortunately we sit on a patch in the ocean whose atmosphere has been suffering the prolonged pangs of other industrial nations’ greenhouse gas output that has been chronically deteriorating our ozone layer over time. So we have to be extra vigilant here.

Of course we should be out in the sun, having fun and playing in the sea with our loved ones, but at the same time we should be mindful of the damaging effects of overt UV exposure. I hope this article has helped outline some of the complexities of sun creams and also alerted you to other ways with which you can protect yourself and your family this summer.

With sonnet VXIII, I think William Shakespeare was advocating the use of sun cream – before it had even been invented!

“Shall I compare thee to a summer’s day?
Thou art more lovely and more temperate:
Rough winds do shake the darling buds of May,
And summer’s lease hath all too short a date:
Sometime too hot the eye of heaven shines,
And often is his gold complexion dimmed,
And every fair from fair sometime declines,
By chance, or nature’s changing course untrimmed:
But thy eternal summer shall not fade,
Nor lose possession of that fair thou ow’st,
Nor shall death brag thou wander’st in his shade,
When in eternal lines to time thou grow’st,
So long as men can breathe, or eyes can see,
So long lives this, and this gives life to thee.”

In moderation we shall enjoy the sun, have fun everyone!

by Christopher von Roy BSc, MSc, DCP Immunology

References

http://www.webmd.com/beauty/sun/sunscreen-safety-labels-ingredients
http://www.lef.org/magazine/mag2007/jun2007_report_sunscreen_01.htm


http://www.ewg.org/2013sunscreen/the-trouble-with-sunscreen-chemicals/
http://www.lef.org/magazine/mag2006/jun2006_report_sunscreen_01.htm
http://en.wikipedia.org/wiki/Potential_health_risks_of_sunscreen
http://www.lef.org/magazine/mag2013/apr2013_Astaxanthin-Provides-Broad-Spectrum-Protection_01.htm
Demir G, Klein HO, Mandel-Molinas N, Tuzuner N. Beta glucan induces proliferation and activation of monocytes in peripheral blood of patients with advanced breast cancer. Int Immunopharmacol. 2007 Jan;7(1):113-6.
Dvorakova K, Dorr RT, Valcic S, Timmermann B, Alberts DS. Pharmacokinetics of the green tea derivative, EGCG, by the topical route of administration in mouse and human skin. Cancer Chemother Pharmacol. 1999;43(4):331-5.
Ho CT, Wang M, Wei GJ, Huang TC, Huang MT. Chemistry and antioxidative factors in rosemary and sage. Biofactors. 2000;13(1-4):161-6.
Altinier G, Sosa S, Aquino RP, et al. Characterization of topical antiinflammatory compounds in Rosmarinus officinalis L. J Agric Food Chem. 2007 Mar 7;55(5):1718-23.
Saeedi M, Morteza-Semnani K, Ghoreishi MR. The treatment of atopic dermatitis with licorice gel. J Dermatolog Treat. 2003 Sep;14(3):153-7.

We’d Love Your Feedback

How do you protect yourself from excessive UV exposure? Have you found a sun cream that is effective? Do you use supplements to help support and protect against skin damage?