Older people with low blood levels of vitamin D and high blood levels of parathyroid hormone are more likely to be depressed, according to a new report. It remains unclear whether these are causes or consequences of depression.
Past studies have linked altered levels of vitamin D and parathyroid hormone with depression, but the relationship has never before been studied systematically. Researchers examined more than 1200 men and women aged 65 to 95.
Nearly 40 percent of the men and 57 percent of women had low levels of vitamin D in their blood; vitamin D levels averaged 14 percent lower among the 195 people suffering from depression. Blood levels of parathyroid hormone, which increase with vitamin D deficiency, were 5 percent higher in people with minor depression and 33 percent higher in those with major depression.
* Reuters May 5, 2008