quality:corruption
Vitamin D

Sunlight, fortified foods, and dietary supplements are the main sources of vitamin D for vegans. Humans produce vitamin D naturally in response to sun exposure and ultraviolet light (UV) acting on skin to stimulate vitamin D synthesis. UV light penetrates the skin at wavelengths between 290 and 320 nanometers, where it is then converted into vitamin D. Vitamin D can be obtained from fungi, such as mushrooms exposed to sun or industrial ultraviolet light, offering a vegan choice for dietary or supplemental vitamin D. Plant milks, such as from oat, soy, or almond, and breakfast cereals are commonly fortified with vitamin D.