本文发表在 rolia.net 枫下论坛Adequate Levels of Vitamin D
Getting enough vitamin D is a challenge especially in northern climates. Evolution has given us the ability to produce vitamin D naturally within our body. It can be synthesized just under your skin with proper exposure to sunlight. Adequate amounts of vitamin D can be made in the skin after only ten to fifteen minutes of sun exposure at least two times per week to the face, arms, hands, or back without sunscreen. However, season, geographic latitude, time of day, cloud cover, skin cover, skin colour, smog, and sunscreen affect UV ray absorption and vitamin D synthesis. For example, sunlight exposure from November through February in Canada is insufficient to produce significant vitamin D synthesis in the skin. The UV rating must be above 3 for sunlight to be effective in producing vitamin D in our skin. Vitamin D-deficient diets are associated with milk allergy, lactose intolerance, ovo-vegetarianism, and veganism. Rickets and osteomalacia are the classical vitamin D deficiency diseases. In children, vitamin D deficiency causes rickets, a disease characterized by a failure of bone tissue to properly mineralize, resulting in soft bones and skeletal deformities. In adults, vitamin D deficiency can lead to osteomalacia, resulting in weak bones. Symptoms of bone pain and muscle weakness can indicate inadequate vitamin D levels, but such symptoms can be subtle and go undetected in the initial stages. (Ref. ODS)更多精彩文章及讨论,请光临枫下论坛 rolia.net
Getting enough vitamin D is a challenge especially in northern climates. Evolution has given us the ability to produce vitamin D naturally within our body. It can be synthesized just under your skin with proper exposure to sunlight. Adequate amounts of vitamin D can be made in the skin after only ten to fifteen minutes of sun exposure at least two times per week to the face, arms, hands, or back without sunscreen. However, season, geographic latitude, time of day, cloud cover, skin cover, skin colour, smog, and sunscreen affect UV ray absorption and vitamin D synthesis. For example, sunlight exposure from November through February in Canada is insufficient to produce significant vitamin D synthesis in the skin. The UV rating must be above 3 for sunlight to be effective in producing vitamin D in our skin. Vitamin D-deficient diets are associated with milk allergy, lactose intolerance, ovo-vegetarianism, and veganism. Rickets and osteomalacia are the classical vitamin D deficiency diseases. In children, vitamin D deficiency causes rickets, a disease characterized by a failure of bone tissue to properly mineralize, resulting in soft bones and skeletal deformities. In adults, vitamin D deficiency can lead to osteomalacia, resulting in weak bones. Symptoms of bone pain and muscle weakness can indicate inadequate vitamin D levels, but such symptoms can be subtle and go undetected in the initial stages. (Ref. ODS)更多精彩文章及讨论,请光临枫下论坛 rolia.net