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  2. Health effects of sunlight exposure - Wikipedia

    en.wikipedia.org/wiki/Health_effects_of_sunlight...

    Exposure of skin to ultraviolet radiation from sunlight presents both positive and negative health effects. On the positive side, UV exposure enables the synthesis of vitamin D3, which is essential for bone health [1] and potentially plays a role in inhibiting certain cancers. [2][3] While vitamin D can also be obtained through dietary ...

  3. Skin care - Wikipedia

    en.wikipedia.org/wiki/Skin_care

    Skin care. Skin care or skincare is a range of practices that support skin integrity, enhance its appearance, and relieve skin conditions. They can include nutrition, avoidance of excessive sun exposure, and appropriate use of emollients. Practices that enhance appearance include the use of cosmetics, botulinum, exfoliation, fillers, laser ...

  4. Photosynthetically active radiation - Wikipedia

    en.wikipedia.org/wiki/Photosynthetically_active...

    Photosynthetically active radiation (PAR) designates the spectral range (wave band) of solar radiation from 400 to 700 nanometers that photosynthetic organisms are able to use in the process of photosynthesis. This spectral region corresponds more or less with the range of light visible to the human eye. Photons at shorter wavelengths tend to ...

  5. Ultraviolet index - Wikipedia

    en.wikipedia.org/wiki/Ultraviolet_index

    The ultraviolet index, or UV index, is an international standard measurement of the strength of the sunburn -producing ultraviolet (UV) radiation at a particular place and time. It is primarily used in daily and hourly forecasts aimed at the general public. The UV index is designed as an open-ended linear scale, directly proportional to the ...

  6. Skin cancer - Wikipedia

    en.wikipedia.org/wiki/Skin_cancer

    Skin cancers are cancers that arise from the skin. They are due to the development of abnormal cells that have the ability to invade or spread to other parts of the body. [10] It occurs when skin cells grow uncontrollably, forming malignant tumors. The primary cause of skin cancer is prolonged exposure to ultraviolet (UV) radiation from the sun ...

  7. Indoor tanning - Wikipedia

    en.wikipedia.org/wiki/Indoor_tanning

    Indoor tanning involves using a device that emits ultraviolet radiation to produce a cosmetic tan. [a] Typically found in tanning salons, gyms, spas, hotels, and sporting facilities, and less often in private residences, the most common device is a horizontal tanning bed, also known as a sunbed or solarium. Vertical devices are known as tanning ...

  8. Solar activity and climate - Wikipedia

    en.wikipedia.org/wiki/Solar_activity_and_climate

    Solar activity and climate. Solar irradiance (yellow) plotted with temperature (red) since 1880. Patterns of solar irradiance and solar variation have been a main driver of climate change over the millions to billions of years of the geologic time scale. Evidence that this is the case comes from analysis on many timescales and from many sources ...

  9. Sunlight - Wikipedia

    en.wikipedia.org/wiki/Sunlight

    The ultraviolet radiation in sunlight has both positive and negative health effects, as it is both a requisite for vitamin D 3 synthesis and a mutagen. Sunlight takes about 8.3 minutes to reach Earth from the surface of the Sun. [ 3 ] A photon starting at the center of the Sun and changing direction every time it encounters a charged particle ...