General Knowledge - Basic General Knowledge - Discussion

Sunlight means only morning light. Sunlight after morning contains much amount of uv rays which is harmful to body.

After reading various answer. I reached on this result that UV ray with low frequency are not harmful for us.

Actually, uv rays affects the skin, means skin cancer and other skin diseases. Then how will these rays form vit D very little amount of rays enters atmosphere.

@Vanitha.

Actually there are three types of u.v. rays depending upon it's wavelength.. (u.v.A 320-400 NM) & (u.v.B 280-320 NM) & (u.v.C 200-280 NM) actually u.v..c is cut off by ozone layer while we get maximum exposure to u.v.A & u.v.B because it is closer to visible wavelength which we can see with our eyes. rainbow color.

Vitamin D3 is made in the skin with ultraviolet light of UVB type at wavelengths between 270 and 300 nm, with peak synthesis occurring between 295 and 297 nm, which is then converted into active form of Vitamin D which is necessary for body defense mechanism.

The body basically need daily sunlight to produce vitamin d since vitamin cannot be stored in body like fat & proteins.. so daily exposure is necessary in morning.

Vitamin D is a fat-soluble vitamin which can provide for the body's needs in one of two ways. Through the action of sunlight on the skin, or through the major food sources of cod liver oil, cold-water fish, butter, and egg yolks. When the sun shines on the skin, the ultraviolet rays activate a form of cholesterol which is present in the skin, converting it to Vitamin D (1). Because the body can provide sufficient Vitamin D to meet its needs simply through exposure to sunlight, some feel it is not really a vitamin, but instead is a hormone.

Friends very less amount of UV-rays doesn't affect our cell tissues. So its better to stand out in morning sunlight.

Dark circles doesn't come through sun light to prevent that you have to sleep properly. Don't allow dusts and oil on your face for long time at-least have to wash our face with cold water 6 times in a day and don't use soap more than twice.

Can you explain the pimples problem and dark circles.

I think UV rays are very harmfull then how can it convert into Vitamin D.

I didn't get a pasitive about it. Please, can anybody explain ?

In the evening the sun is not present, so how the uv ray is helpfull to our body?