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Top of the page. Share sensitive information only on official, secure websites. JavaScript appears to be disabled on this computer. Please click here to see any active alerts. Tanning is your body's attempt to protect itself from being damaged by ultraviolet UV radiation.
While we need some exposure to sunlight to help our bodies make vitamin D, too much UV is dangerous. Source: U. Almost half the daytime total of the more harmful UVB radiation is received between the hours of 10 a. Light enables us to see, and heat keeps us from being cold. However, ultraviolet rays often carry the unfortunate circumstance of containing too much energy. For example, infrared rays create heat in much the same way as rubbing your hands together does. The energy contained in the infrared rays causes the molecules of the substance it hits to vibrate back and forth.
However, the energy contained in ultraviolet rays is higher, so instead of just causing the molecules to shake, it actually can knock electrons away from the atoms, or causes molecules to split. This results in a change in the chemical structure of the molecule. This change is especially detrimental to living organisms, as it can cause cell damage and deformities by actually mutating its genetic code.
This is simply a convenient way of classifying the rays based on the amount of energy they contain and their effects on biological matter. Luckily,UV-C rays do not reach the earth's surface because of the ozone layer.
When UV-C rays meet the ozone molecules at high layers of the atmosphere, the energy inherent in them is enough to break apart the bond of the molecule and absorb the energy. Therefore, no UV-C rays from the sun ever come into contact with life on earth, though man-produced UV-C rays can be a hazard in certain professions, such as welders.
As their energy is often not sufficient to split an ozone molecule, some of them extend down to the earth's surface. UV-A rays do not have enough energy to break apart the bonds of the ozone, so UV-A radiation passes the earth's atmosphere almost unfiltered.
This can be done through a variety of ways. The most obvious is to reduce the amount of time one spends in the sun, particularly between the hours of 11 am and 3 pm, when the sun is at its highest in the sky.
However, especially during the summer holidays, this does not always work out. Some US states have already banned indoor tanning by all people younger than 18, while others have banned use by younger teens and children. In addition to skin cancer , exposure to UV rays can cause other health problems:.
Some people are more sensitive to the damaging effects of UV radiation. Some medications can also make you more sensitive to UV radiation, making you more likely to get sunburned. And certain medical conditions can be made worse by UV radiation. Your skin makes vitamin D naturally when it is exposed to UV rays from the sun. How much vitamin D you make depends on many things, including how old you are, how dark your skin is, and how strong the sunlight is where you live.
Vitamin D has many health benefits. It might even help lower the risk of some cancers. Dietary sources and vitamin supplements do not increase skin cancer risk, and are typically more reliable ways to get the amount you need.
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