When people talk about a vitamin D light, they are usually referring to a machine that creates ultraviolet (UV) light, which helps produce vitamin D in the body. This type of UV light is also available naturally from the sun. If a vitamin D light isn't available, many individuals who don't get enough sunlight choose to use supplements to increase their vitamin D levels.
UV light, specifically ultraviolet-B (UVB) light, is what is responsible for vitamin D production in the skin. Production is best when the light's wavelengths are between the range of 270–300 nanometers. Peak synthesis can happen at 295-297 nanometers. These conditions can occur when sunlight presents a UV index of at least 3. Regions such as the tropics can experience these conditions every day, and others, such as in the arctic circles, are almost entirely devoid of them.
Many people consider the best source of vitamin D light to be the sun. It's a free, natural source of vitamin D that the skin is suited to absorb. Exposing the skin to sunlight can increase vitamin D production to healthy levels. Spending just a few minutes outside underneath the the midday sun can significantly increase vitamin D production. The skin, however, should not be over-exposed to the sun, as it can increase the risk for burning and skin disorders.
People who live in cold climates or who can't spend time outside at the proper times can look into purchasing and using a vitamin D light. Vitamin D lights are special devices that resemble heaters and emit UV waves. The UVB bands that a vitamin D light produces speeds vitamin D production in its user. Using a vitamin D light can help combat the effects of seasonal affective disorder (SAD). Another benefit of using a vitamin D light is that its use does not result in tanning.
Those who live in a region without an adequate UV index and who can't tolerate sunlight or find a vitamin D light might turn to supplements to keep their vitamin D levels stable. When shopping for vitamin D supplements, consumers should look for vitamin D3, also known as cholecalciferol. This form of vitamin D is the type of vitamin D that would be naturally produced in the consumer's skin, had he or she spent time underneath sunlight. Another form of vitamin D, D2, presents possible toxicity problems and is available only by prescription. Many people supplement with oral D3 while using vitamin D lights to increase their vitamin D levels, though dosages have to be monitored.