：关于是否应该补充维生素的问题一直争论不断，不时有新的研究成果发表。维生素D在公众的印象中是防止缺钙的，但是最新一项研究结果表明情绪低落、抑郁等也可能是因为缺乏维生素D。
荷兰科研人员对1282名65―92岁的老人进行了调查，其中26人患有重度抑郁，169人患有轻度抑郁，其他人没有抑郁症状。结果发现，患有抑郁的老人体内维生素D水平比其他老人低14%。研究还发现，维生素水平低会影响某种激素的分泌，从而引发抑郁。
研究人员表示，这项研究为人们补充维生素D提供了又一个科学支持，“以前有研究显示晒太阳能缓解抑郁，这也与维生素D有一定关系，因为晒太阳是补充维生素D的好方法；另外，根据国际标准，70岁以上老人的每日应摄入600国际单位。”（
Archives of General Psychiatry，65(5):508-512，Witte J. G. Hoogendijk，Brenda W. J. H. Penninx
Depression Is Associated With Decreased 25-Hydroxyvitamin D and Increased Parathyroid Hormone Levels in Older s
Witte J. G. Hoogendijk, MD, PhD; Paul Lips, MD, PhD; Miranda G. Dik, PhD; Dorly J. H. Deeg, PhD; Aartjan T. F. Beekman, MD, PhD; Brenda W. J. H. Penninx, PhD
Context Depression has incidentally been related to altered levels of 25-hydroxyvitamin D [25(OH)D] and parathyroid hormone (PTH), but this relation has never been studied systematically.
Objective To determine in a large population-based cohort whether there is an association between depression and altered 25(OH)D and PTH levels.
Design Population-based cohort study (Longitudinal Aging Study Amsterdam).
Participants One thousand two hundred eighty-two community residents aged 65 to 95 years.
Setting The Netherlands.
Main Outcome Measure Depression was measured using self-reports (Center for Epidemiologic Studies–Depression scale) and diagnostic interviews (Diagnostic Interview Schedule). Levels of 25(OH)D and PTH were assessed. Potentially confounding factors (ie, age, sex, oking status, body mass index, number of chronic conditions, and serum creatinine concentration) and explanatory factors (ie, season of data acquisition, level of urbanization, and physical activity) were also measured.
Results Levels of 25(OH)D were 14% lower in 169 persons with minor depression and 14% lower in 26 persons with major depressive disorder compared with levels in 1087 control individuals (P < .001). Levels of PTH were 5% and 33% higher, respectively (P = .003). Depression severity (Center for Epidemiologic Studies Depression Scale) was significantly associated with decreased serum 25(OH)D levels (P = .03) and increased serum PTH levels (P = .008).
Conclusion The results of this large population-based study show an association of depression status and severity with decreased serum 25(OH)D levels and increased serum PTH levels in older individuals
