Why does over-exposure to the sun cause skin cancer, while under-exposure harms you as well?

Not getting enough sun is bad for you, but too much sun is bad as well. Why is that?
Why does over-exposure to the sun cause skin cancer, while under-exposure harms you as well?
Basically, UV radiation, which is one component of sun light, has a lot of energy, and tends to ionize molecules, including DNA. When something is ionized, its charge changes, and for DNA that causes it to break appart. Your DNA is pretty good at putting itself back together again, but sometimes it ends up in the wrong order, or a couple nucleotides get messed up or replaced with something different. That changes the genetic code that tells your cells what to do. Sometimes those changes mean that your cells get confused about when to grow and divide, and they grow when they're not supposed to, which is basically what causes cancer. Since the UV radiation usually doesn't make it much past the skin, it's mainly skin cells that are effected, so UV light tends to cause skin cancer more than other things.





So too much sunlight is bad, but you do need a little bit to help your body absorb vitamin D. I'm not entirely clear on how this works, but basically, you just need a little bit of light - most people get enough just walking to and from their car, office, grocery store, etc. without having to try to spend time in the sun.
Why does over-exposure to the sun cause skin cancer, while under-exposure harms you as well?
look it up stop asking us
Reply:Well, it's okay to be out in the sun as long as your skin is protected (either by clothing, shade, and/or sunblock). Lack of sun can create a Vitamin D deficiency, especially in older folks. I guess it's the same as everything in life: moderation is key!
Reply:Too much UV exposure leads to mutagenic changes in the dermis. Too little leads to Vitamin D deficiency, and has been linked to SADS (seasonal affective disorder syndrome (depression)).
Reply:Under exposure harms you from the standpoint that certain vitamins are synthesized from the ultraviolet rays. These vitamins cannot be produced by the body without the sun's light, however, they can be artificially produced and taken in pill form. Over-exposure to the sun will lead to premature aging and melanoma. There is no alternative to this. So if you are making the choice, I say get some vitamin K and D pills and hide in a cave, at least you will stay wrinkle-free into your 90s!
Reply:It is just a matter of susceptibility. Some people like me burn so much easier than a darker complected person.Some people will get cancer easier than others.
Reply:In the end most things in life come down to BALANCE
Reply:1st due to pollution OZONE layer is damaged,


2nd Uv rays are deadly.


For example - a sleeping pill may give u a good sleep for hours


and ten sleeping pills may give u good sleep for rest of ur life.


So anything too much is not good.
Reply:Sunlight is required for the production of Vitamin D , and vitamin D is required so that your body can absorb calcium. However over exposure to the harmful UVA rays causes deep penetration of the skin's cells and increases your risks for cancer.


Think of like this..... a piece of cake is great but eating an entire cake , not so great.
Reply:In order for the body to produce the vitamin D needed to effectively use calcium, exposure to the sun is needed. However, the overexposure to the sun allows the UV rays to effect the structure of the skin cells which may lead to skin cancer at a later time. When we receive repeated sun burns, we are receiving small amount of radiation that can lead to cancer. Most of the damage is usually done before the age of 25.
Reply:The sun provides a lot of sources to where we get our Vitamin D...the light factor is important to our mental health. If you take a person that gets plenty of light for their body to feed on and one who is keep in the darker realms.....the lighter one will have less signs of depression! So let the light in!!


On the other hand - to much of something never is good...even the sun...premature aging is caused by this. I knew someone that worked out in the sun most of his life....he looked 20 years older than what he said he age was....I was embarrassed when he asked me how old I thought he was!


As to the skin cancer.........many studies are now saying to watch what sunscreens you put on because it's the chemicals in them that are causing a lot of the skin cancer issues!


Something to think about!


Think about it...............how many people in Zimbabwa and Africa get skin cancer? They don't smear those man made chemicals all over there body!





SmileyCat : )
Reply:Over exposure to the sun, increases the chances that ultraviolate light penetrating your sknin will cause a kink in your DNA by creating a dimmer between two adenine residues in the same strand, their are enzymes in your cells that will repair these kinks, but the more times this occurs the greater chance that it might not be repaired and create problems. The vitamin D which is really a hormone is created in your skin cells when exposed to sun light, and is necessary for many biological functions.
Reply:ultra violet rays are carcinogenic. Underexposure would harm only if you did not get any vitamen D otherwise and got rickets
Reply:DO YOU HAVE ANY IDEA HOW THICK YOUR FRIGGIN' SKIN IS?! [SARCASM] THE SUN'S MIDDLE-AGED AND IT'S AS POWERFUL AS HELL.
Reply:overexposure to the sun (uv light) will cause mutation of certain DNA molecules (most notably thymine dimers), too much mutation in certain genes will cause irrepairable damage to the DNA which will then cause certain protein to be overproduce uncontrollably (cancer).


underexposure to the sun (uv light) will cause deficiency of Vitamin D (Vitamin D need uv light to be converted from a non-active form to an active form), and thus will cause certain diseases.
Reply:Just like the earth has to have balence, so does your body. There are certain things that your body needs from the sun. But to much can hurt you as well. Just like not eating enough harms your body but too much can be harmfull too! I hope this helps.
Reply:Natural sun light was always a part of what keeps the earth alive. We will die without it. It causes the plants to grow and helps our bodies to release hormones to make us healthy. The ozone layer is depleting and now it is alot more harmful than it was years and years ago. That's just the way things work there is always too little and too much of something.