VITAMIN D AND BONE STATUS IN THE ELDERLY

众所周知，暴露在阳光下是绝对必要的。 为了发展和维护人类健康的骨骼，当 维生素D的饮食来源不充足。波长的辐射 小于316纳米的纳米开始在人类皮肤中产生维生素D， 它的缺乏现在被认为是一个健康问题 欧洲和美国的老年人。阳光包含一种 所需生物活性UVB波长的一小部分 皮肤维生素D合成和一般活动的个人，一个 正常的生活方式提供了充足的阳光照射，以保持 健康的维他命D状态。然而，众所周知，年龄会减少这一数量 皮肤中维生素D前体的含量，再加上缺乏 老年人和体弱者进行的户外活动会使人筋疲力尽 与维生素D缺乏相关的疾病。为了解决这个问题， 我们需要知道一年中有多少阳光照射。 对健康来说是必需的。后一个量不仅是时间的函数， 还包括裸露的皮肤面积、季节和纬度。这项研究将 评价衰老对体内皮肤维生素D合成的影响 年志愿者天然中波紫外线暴露及维生素D状况监测 养老院环境中定义明确的老年人群体。 (A)太阳光谱与光谱的比较 荧光灯和(B)荧光灯的能力 促进皮肤维生素D3的合成将使 就利用太阳辐射作为一种手段提出建议 为老年流动居民维持充足的维生素D营养 对于UVB增强型照明的可能开发，可能会 用于医院病房和疗养院的虚弱病人 易患维生素D缺乏症，不能外出。

It is well recognized that exposure to sunlight is absolutely essential for the development and maintenance of a healthy skeleton in humans when dietary sources of vitamin D are not adequate. Radiation of wavelengths less than 316 nm initiates the production of vitamin D in human skin, a deficiency of which is now being recognized as a health problem amongst the elderly both in Europe and the United States. Sunlight contains a small component of the biologically active UVB wavelengths required for cutaneous vitamin D synthesis and for a generally mobile individual, a normal lifestyle provides sufficient sunlight exposure to maintain a healthy vitamin-D status. However, age is known to decrease the amount of vitamin-D precursor in the skin, and this, together with the lack of outdoor activity undertaken by the elderly and infirm, leads to the bone diseases associated with vitamin-D deficiency. To combat this problem, we need to know how much sunlight exposure throughout the year is required for health. The latter quantity is a function not only of time, but also of skin area exposed, season, and latitude. This study will assess the affect of aging on cutaneous vitamin D synthesis in vivo by monitoring the natural UVB exposure and vitamin-D status of volunteers in a well defined population of elderly in a nursing home setting. Comparison of the (a) solar spectrum with the spectrum with the spectra of fluorescent lights and (b) the capacity of fluorescent lighting to promote cutaneous previtamin D3 synthesis will then enable recommendations to be made for the use of solar irradiation as a means of maintaining adequate vitamin-D nutrition for the elderly mobile residents and for the possible development of UVB-enhanced lighting that could be used in hospital wards and nursing homes for infirm patients who are susceptible to vitamin-D deficiency and cannot go outdoors.