Low levels of vitamin D in elderly people may lead to depression and other psychiatric problems, Dutch researchers said.

"Underlying causes of vitamin D deficiency such as less sun exposure as a result of decreased outdoor activity, different housing or clothing habits and decreased vitamin intake may be secondary to depression, but depression may also be the consequence of poor vitamin D levels," the study, released Monday, said.

Researchers from Vrije Universiteit, Amsterdam, studied some 1,282 senior citizens aged between 65 and 95, and found 26 had major depression, while 169 suffered from minor depression.

Vitamin D levels were 14 percent lower in those elderly suffering from some kind of depression, according to the study published in the Archives of General Psychiatry.

It found that poor vitamin D status also led to an increase in levels of a hormone secreted by the parathyroid. Overactive parathyroid glands are frequently associated with depression.

The findings could be important in treating depression as both low blood vitamin D levels and high parathyroid hormone levels can be corrected by dietary and calcium supplements or increased exposure to sunlight.

"Moreover, the clinical relevance of the present study is underscored by our finding that 38.8 percent of men and 56.9 percent of women in our community-based cohort had an insufficient vitamin D status," the study added.

荷兰研究人员日前称，老年人体内的维生素D水平低可能会导致抑郁症及其它精神问题。

本周一公布的一项研究称，“户外活动减少、不同的居住条件或穿衣习惯引起晒太阳时间减少，以及维生素摄入量减少，这些都是体内缺乏维生素D的潜在原因，它们或许不是导致抑郁症的直接原因，但是抑郁症可能是体内维生素D水平低造成的。”

阿姆斯特丹自由大学的研究人员对约1282名年龄在65岁到95岁间的老年人进行了研究，结果发现其中有26人患有重度抑郁，169人患有轻度抑郁。

该研究指出，患有不同程度抑郁症的老年人体内的维生素D含量要低14%。该研究在《普通精神医学档案》上发表。

研究发现，人体内的维生素D含量低还会导致甲状旁腺分泌的激素增多。而甲状旁腺过度活跃常与抑郁症有关。

这些研究结果对于治疗抑郁症很重要，因为血液中维生素D含量低以及甲状旁腺激素水平过高都可通过饮食、补钙或多晒太阳来改善。

研究人员称：“此外我们的研究发现，在以社区为单位的研究小组中，有38.8%的男性和56.9%的女性缺乏维生素D。这一发现增强了该研究的临床实用性。

Vocabulary:

secrete:分泌