What in the heck are LEDs anyway? – Part 3 The good, the bad & the beautiful
So, what have we learned about light therapy so far….
In part 1 of this blog series we reviewed the different electromagnetic rays that the sun produces. In part 2 we gained a deeper understanding of which of those rays are important for us to understand as estheticians, but so what? What do all of these rays actually DO to the skin?
Some is good, some is bad, and some is…. beautiful!
Let’s mix it up – First up – the BAD! We know that in general UV rays are bad for the skin, but why? What do they actually do to our skin on a cellular level?
UVA rays, also known as the ‘aging’ rays, account for about 95% of the UV radiation that reaches the earth’s surface. These UVA rays are low energy UV rays that penetrate deep into the dermis. They are known as the aging rays because they cause fragmentation of the collagen and elastin fibers, which make up the support framework of the skin. As these fibers are damaged, you will see lines and wrinkles appear. UVA rays have the same intensity year round, even on a cloudy day. When you apply a broad-spectrum sunscreen with an SPF 30 you are protecting yourself from only about 1/3 of the UVA rays. These rays are able to penetrate glass, which is why we need to wear sunscreen daily, even when we are in our cars or our office buildings.
UVB rays, also known as the ‘burning’ rays are most prevalent from April through October, 10 AM – 4 PM in the United States. These rays are only able to penetrate the epidermis and are the chief cause of sunburning. UVB rays play a key role in the development of skin cancer and also contribute to photo-aging. When you apply a broad-spectrum sunscreen with SPF 30 you are protecting yourself from about 93% of the UVB rays. UVB rays can burn and damage the skin year round, especially at higher altitudes and on reflective surfaces, such as snow, water or ice. These UVB rays do not significantly penetrate glass.
UVC rays do not penetrate the earth’s atmosphere and are lethal to living cells.
So, before you go thinking that ALL UV exposure is bad – keep this in mind…. There are several positive cellular responses to UV stimulation by our skin – but this exposure is beneficial ONLY in moderation and with appropriate sun protection! Remember, you can NOT block 100% of UV radiation without hiding in a black box that has absolutely no UV exposure! UV radiation stimulates chemical activity in the skin, increasing cellular regeneration and desquamation, it kills some bacteria on the skin, it stimulates the production of Vitamin D in the skin as well as having a beneficial effect on some skin disorders, such as psoriasis and acne.
Duh – In general, UV rays are bad for our skin, so what’s the deal with the visible and infrared spectrum? Let’s put it all together now.