The sun and the sunscreen

Growing up in the middle east with shade of brown skin I had never heard of the sun being bad for you. In fact I adored the sun. The more it shined on me the happier I was as a kid. That is until I moved to California and was introduced to the world of colorful sunblock lotions well displayed in the grocery store. But even then I was on a path of self destruction. Among many options I chose the one and only one that not only did not help, but actually did more harm: the coconut oil. It smelled great and it made me look even more tanned. I was not really properly introduced to sun block world until I met Megan Coleman, now better known as Megan Moini. A pale white girl from deserts of Oregon and the sun state of Florida, she was obsessed. Soon I was educated on the dangers of sun exposure and something called skin cancer. We have an array of sun block lotions in our house.

And now that the sun has finally made its beautiful shiny face visible to Cleveland, let's review some basics on how to enjoy the sun while also protecting your skin.

The sun emits an array of beams, some of which make it to the earth. These beams are classified based on the wave length. The two most important sunbeams for us humans are the Ultraviolet A (UVA) and Ultraviolet B (UVB).

In small doses UVB actually is essential for Vitamin D synthesis. UVB penetrates the outer layer of skin and activates a specific lipid that we store in our skin cells ( 3-hydroxycholesterol) to Pre-Vitamin D. Pre-Vitamin D is then converted to 25-hydroxy Vitamin D in the liver and finally to the active form 1-25hydroxy Vitamin D in the kidneys. So, we need a healthy sun exposure, a healthy liver and a healthy kidney to generate adequate Vitamin D. It is estimated that we need direct sun exposure to arms and legs, or face and arms for at least 15 minutes, three times a day to generate enough Vitamin D. But this does not take into account time of day, skin color (darker skin needs more time), altitude and latitude. Generally, the sun beam is stronger as you go to higher elevations and closer to equatorial line, For us Clevelanders, it is safe to say that we do not get enough exposure during the cold months when we are covered and do not spend enough time outside.

Now, this does not mean that you should expose yourself to more direct sun when the sun does shine. Because as most of you know sun can also cause skin cancer.

Sun and skin cancer:

UVB, the same beam that provides us with Vitamin D, can also give us skin cancer. UVB causes direct damage to our skin DNA. The strong ultraviolet light causes damage to the nucleic acids that form the backbone of DNA, at times leading to changes that cause the skin cells to start dividing in an unregulated excessive way, better known as cancer . It also reduces the skin's ability to fix the damage by dampening the skin's immune response. This is a double whammy that increases the risk of skin cancer.

On the other hand, UVA penetrates deeper in the tissue, causing formation of free radical oxygen species (ROS). ROS are potent chemicals that are highly reactive and can damage various parts of the cell. Think of them as a fully loaded soldier gone rogue. ROS can lead to DNA damages that also leads to skin cancer.

In addition, excessive sun exposure causes wrinkling of the skin and various skin color spots that can be permanent.

There is no magic safe time under the sun. As long as you are not wearing appropriate sunblock, no time is safe time. But there seems to be some pattern on amount of sun exposure and risk of skin cancer:

Basal Cell Carcinoma: Associated with cumulative sun exposure. So, one time in the beach wont do it, but many summer days will.

Melanoma: Associated with single severe sun exposure (think burn blisters).

Squamous Cell Carcinoma: both cumulative and single exposure are risk factors.

In addition, the most potent UVA and UVB exposure are between 10am and 4pm, but it is best practice to apply a form of sunblock for any exposure between 9am and 7pm. And for those parents out there, the young and adolescent ages are particularly high risk for future skin cancer. So before your kids run out the door to play in the sun, be sure to shower them with sunblock love.

Type of Sunblock:

There are generally two types of sunblock:

1) Physical:

a) simply covering the body. This means long sleeve dark shirt, pants, large hats that cover the head and neck. Might as well just stay inside!

b) Using creams that block the sunbeam from penetrating the skin. These are also referred to as "inorganic sunblock." The two options in the US are Zinc Oxide and Titanium Dioxide. This is a thick cream that forms a protective layer over t he skin surface without actually being absorbed into the skin,. It works by absorbing the UVA and UVB, preventing them from getting to the skin. They are highly effective and since they are not actually absorbed they do not cause skin irritation or any potential biohazards. Only downside is that you will have a thick white layer on your skin, so you may not be the most attractive person walking down the beach.

c): Clouds: although clouds may reduce the amount of UVA and UVB, but they do not fully protect you, so you still need sunscreen if you are going to be out for a prolonged time in the summer months.

2) Chemical:

Chemical sunscreens are the most common types of sunscreen you will see displayed in the stores. These are chemicals that are absorbed by the skin and work by converting UVA and UVB into heat, therefore dissipating the damaging force of the sun beams. They can cause skin irritation and since they are absorbed by the skin, they enter the blood stream. Although there is no actual evidence, but there is some theoretical risk of the absorbed chemicals to be hazardous to your health.

Both types of sunblock are equally effective and really which one you use depends on your own personal preferences. The minimum Sun Protective Factor (SFP) recommended is 15, but dermatologist and the skin cancer society recommend an SPF of 30. There is little benefit in using SPF above 30. Personally I use the chemical type as it makes less of a mess and it does not get all over my clothes specially when I exercise. But my wife and the kids use the Inorganic type as it is less irritating to the skin and does not get absorbed.

Regardless of the type, sunscreen should be applied generously to the exposed areas every 2-4 hours. So, if like me you apply first thing in the day to satisfy your wife's judging eyes and then never come back to it, you are not really protecting your skin. Being in the water or sweating excessively also reduces the protective time, so reapply more frequently (closer to every 2 hours than 4).

And no, there is no one brand that I recommend. The active ingredient in all commercially available brands are the same and regulated, so as long as it is SPF 30, it is safe and effective. One difference is all the added stuff like scents, antiaging and whatever else is the trend. These accessories are not regulated and can cause excessive skin irritation. So your dermatologist may recommend a brand that is less irritating and has other benefits like moisturizing effect. The sun protective effect is purely based on the SPF and equal among all brands.

So, before you head out the door and enjoy the sun for the next three months, be sure to apply a thick layer of sun screen to all exposed skin areas every 2-4 hours while you are outside.