There are a number of misconceptions about the interaction between sunlight and skin. In this two part post we look at what we think are the top five most common sun and skin myths.
Myth 1: I can’t get sunburnt on a cloudy day
While clouds may provide welcome relief from the heat and glare of sunlight, they do little to protect our skin from the ultraviolet (UV) rays which cause sunburn, skin cancer and other forms of skin damage. Cloudy days can be dangerously deceptive because they block much of the heat (thermal radiation) which we usually associate with high UV levels. As a result, we tend to assume our skin is not at risk when the weather conditions are overcast and drop our guard in terms of sun protection. Unfortunately, UV radiation is not entirely blocked by clouds and, in some instances, clouds can even intensify these harmful rays.
If you wish to be aware of the dangers on any given day, refer to information on your local UV Index rather than the temperature during that day. In addition, always remain vigilant about protecting your skin when outside, regardless of cloud cover.
For more, check out our recent video:
Myth 2: Glass protects my skin from the sun
This myth is actually half true.
The sun produces three types of ultraviolet (UV) light: UVA, UVB and UVC. Of that which reaches the Earth’s surface, approximately 6% is UVB and 94% UVA. Most standard glass (such as the window glass in homes and cars) blocks only the UVB rays, the shorter wavelengths which cause sunburn. Glass, however, doesn’t block out longer UVA wavelengths, which are responsible for causing wrinkles and long-term skin damage which can lead to skin cancer. This means that glass may stop you from getting sunburnt but it does not protect against the other damaging effects of light. Modern glass tints (such as those used in many cars) may filter out some of the UVA rays, but these are never 100% effective and shouldn’t be relied upon to guard your skin against harmful UVA radiation.
Myth 3: A high Sun Protection Factor (SPF) sunscreen will totally protect me from skin cancer
There are some important factors to consider when using sunscreen, regardless of its SPF rating.
Firstly, most dermatologists advise that sunscreen is only one factor in our defense against the sun and should not be solely relied on to protect skin, particularly during the middle of the day when the sun is most intense.
Wearing protective clothing, including broad brimmed hats and long-sleeved garments made of tight weave fabrics will help reduce your exposure to harmful ultraviolet rays. You should also aim to avoid the sun during the middle of the day (approximately 11am till 3pm) when UV radiation is at its peak or seek shade where possible.
Secondly, always check that your sunscreen is a ‘broad-spectrum’ product, meaning it will protect you from both short and long ultraviolet wavelengths (UVB and UVA), both of which can cause skin damage and lead to cancer.
Finally, studies have found that most people do not use enough sunscreen, you’ll need to apply approximately one teaspoon of sunscreen to each segment of your body (i.e. each arm, leg and your face) to ensure it protects your skin effectively. It is important to apply your sunscreen before you head outside (preferably 15-30 minutes prior) and re-apply it every two hours that you stay in the sun (more regularly if you’re swimming or sweating heavily).
Part two of our sun and skin myths will be published next week
Further reading on Clinuvel.com
‘sunset on a cloudy day’ posted to Flickr.com by Flavia_FF on February 7, 2004 <http://www.flickr.com/photos/mistressf/1274407715/>