As the summer is coming (yes, for one part of the world it is), picture this: vacation, beautiful beach with a clean light sand, a coconut water (Brazilians are crazy about it), a chaise long for laying down and a nice warming sun! Can you imagine yourself lying on the chair for hours long or inside the playing inside the water all day long? Take care!
When you have a sunburn, it is really a burn provoked by the sun ultraviolet (UV) radiation. Besides the uncomfortable feeling of pain, hot to the touch, fatigue and even nausea. It can be avoided by usage of sunblocks, hats, umbrellas and, used by many people nowadays, clothing. The only cure for it is slow healing, although some skin creams can help with the symptoms. To avoid it, what if we expose our nice bodies to the sun slowly,in short periods of time day by day. This way the moderate sun tanning without burning can also prevent subsequent sunburn, as it increases the amount of melanin, the skin pigment that protects it against the sun rays, like it is a natural defense of the skin against overexposure (check the post below).

Somebody said moderate suntan?
Here I think it would be useful to mention the two types of UV radiation often mentioned on sunscreens or blockers: the UVA and UVB. The first is more uniformly present through days and seasons and it is blocked more by clothing than by many sunscreens. It is responsible for provoking aging/wrinkles more than UVB and to cause melanomas. UVB causes the direct DNA damage. It is reduced by mostly all sunscreens depending on its sun protection factor (SPF), though it is more likely to cause sunburn as a result of overexposure. Also, it is thought to cause the formation of moles and some non-melanoma skin cancer. Besides, it induces vitamin D production in our skin!
The darkening of the skin, or sun tanning, develops when the UV A radiation oxidizes pre-existing melanin leading to fast darkening of it. It can also be formed by a second mechanism, when the production of melanin (melanogenesis) is increased as a reaction of the body to photodamage from UV B radiation leading to delayed tanning which is just visible about 72 hours after exposure, but lasts longer than the tanning caused by oxidation of existing melanin.
So, the sunburn and the increase in melanin production are both triggered by direct DNA damage provoked by the UV radiation. In both cases or the DNA is repaired and melanin production is increased to prevent future damage, or the cell in which the DNA can't be fixed dies and this leads to skin replacement. Doesn't it sound like sunburn is a warning to keep us out of the bad effects of the sun.

Skin replacement rulez!
Now if indirect DNA damage happens a cancer called malignant melanoma may occur if the damage is not properly repaired. Of course not every exposure to UV results in cancer (read newer post).

I think this hurts a little bit!
These are preventive measures you can follow if you want to suntan, instead of sunburn:
1. Choose sunscreens that block both UVA and UVB. It is important to buy a good brand, to be sure it will not clog your pores or cause allergies.
2. How much to apply? A thick layer, most of us are sorry on how expensive it was and just use a few.

3. Which SPF? It will depend on your skin and how strong is the sun in the place you are going to. I start with minimum SPF 30 for the body and 50 for the face, but I am not so white. My sisters who are much whiter than me start with SPF 50.

4. Remember that even though you applied a nice thick layer of the cream that doesn't mean you can stay the entire day frying at the sun! Best protection is achieved when we apply it 15 to 30 minutes before exposure, followed by one reapplication 15 to 30 minutes after the sun exposure begins. Repeat it after you go swimming, sweat, and rub.
5. Avoid sun exposure between 10 a.m. and 4 p.m. I found the following: "sun rays are stronger at higher elevations (mountains) and lower latitudes (near the equator). One way to deal with time zones, daylight saving time (summer time) and latitude is to check shadow length. If a person's shadow is shorter than their actual height, the risk of sunburn is much higher." Even if you stay under an umbrella, the ray will reflect on the floor to you, wear creams anyway, once I had a nice sunburn of my bikini laces on my sides because of this. It did hurt a lot, and believe me, I was not exposed to the sun!
6. Wear good quality anti-UV sunglasses (I can be mistaken, but I don't think a 10 dollars sunglasses can be good, sorry if I am). Why? If your skin can sunburn, of course your eyes also can.
7. Ah, you are not at the beach and no sand to reflect it back? Be aware that snow and water are very reflective and can greatly increase the amount of UV radiation to which the skin is exposed.
8. Nowadays, some innovations are here or on the way. There are sun protective clothing that were designed specially for outdoor sporters, they can filter the UV radiation. Researchers are developing a type of sunscreen in capsules, you take it and some kind of protection develops on your skin. Interesting isn't it?
9. I keep far from artificial tanning, but this is MY opinion.
The American Academy of Dermatology recommends the use of sunscreens, wearing sun protective clothing and avoiding the sun altogether.
To remember how dangerous sun can be, I can mention that sunburn is not limited only to us animals. It is also significant and common cause of damage to trees and plants whose sunburn is more commonly called as sun-scorching.
So good luck on your next tanning experience! and take care!

Sources: wikipedia, pubmed, www.liguecancer.ch.