7-Dehydrocholesterol has significant absorption of UV light at the lowest wavelengths of light found in sunlight (290-310 nm). Hence the need for full-spectrum lamps to emit UV-B radiation (UV-B light is defined here to be light between 290-315 NM).
In rare cases some vegans might not get enough fat or calories to produce adequate amounts of steroid hormones (which are produced from cholesterol). Two studies have shown vegans to have sex hormones on par with meat-eaters (1, 2), but one report showed vegan women to have lower levels of estrogen (3).
Sheth says that a vegan diet can be healthy as long as you get the nutrients your body needs from a variety of plant-based foods. - Drink plenty of water, as your body may not be used to getting all that extra fiber from the added fruits and vegetables. - Let your doctor know about your new diet.