While researchers have found a relationship between insufficient vitamin D, chronic pain, anxiety and depression, the exact causality is still unknown.
Researchers in a 2007 study reported in Clinical Rheumatology that vitamin D deficiency is common in people with fibromyalgia and also occurs more frequently in those with anxiety and depression. Yet research is also emerging that may dispute the once believed link between Seasonal Affective Disorder, its depressive symptoms and D deficiency.
Regardless of the unanswered questions, patients suffering with mood issues and/or chronic muscle pain may want to consider having their 25-hydroxyvitamin D levels tested.
Fibromyalgia, Vitamin D, Anxiety & Depression May Be Linked
People with fibromyalgia often have symptoms of anxiety and depression as well as low levels of vitamin D. In the 2007 study, researchers tested serum vitamin D levels in 75 patients with fibromyalgia. The subjects completed a Fibromyalgia Impact Questionnaire (FIQ) and Hospital Anxiety and Depression Score (HADS). Results showed that patients with vitamin D deficiency scored higher on the HADS .
Research has also linked vitamin D deficiency to patients who suffer with chronic pain. While the relationship between fibromyalgia, pain, anxiety, depression and vitamin D deficiency is somewhat complex and the exact relationship remains unclear, evidence is mounting to suggest that vitamin D plays some role in chronic pain and mood imbalance.
Vitamin D Deficiency, Depression With Seasonal Affective Disorder Research Disputed
Vitamin D continues to gain worldwide attention due to emerging research linking it to more than 2,000 gene processes in the body. Yet evidence has surfaced to challenge vitamin D’s once presumed role in Seasonal Affective Disorder and the associated depressive symptoms. Researchers believe Seasonal Affective Disorder manifests during winter months as a result of lack of sunlight exposure on the skin which then results in vitamin D deficiency.
In a study published in the Journal of Affective Disorders, Dr. Oscar Franco, Assistant Clinical Professor in Public Health and his team, recruited more than 3,000 people and tested levels of vitamin D (25-hydroxyvitamin D) in the blood. Subjects completed a questionnaire to measure depressive symptoms. Researchers found no clear association between depressive symptoms and the concentration of vitamin D in the blood.
“Few studies have explored the association between blood 25-hydroxyvitamin D concentrations and depression in the general population, ” said Dr. Franco. “Previous studies into the effects of vitamin D supplementation have produced mixed results. More studies are still needed to evaluate whether vitamin D is associated with seasonal affective disorders, but our study does raise questions about the effects of taking more vitamin D to combat depressive symptoms.”
A Japanese study conducted in 2009 also found no evidence linking higher blood vitamin D levels with decreased depressive symptoms.
Vitamin D, Mood & The Brain
In a report entitled, “Vitamin D and the occurrence of depression: causal association or circumstantial evidence?” researchers concluded that based on the body of research to date, high doses of supplemental vitamin D may improve mild depressive symptoms. Yet questions persist regarding the following critical study areas of mood regulation:
- how vitamin D affects monoamine function and hypothalamic-pituitary-adrenal axis response to stress
- whether vitamin D supplementation can improve mood in individuals with moderate-to-severe depression
- whether vitamin D sufficiency is protective against incident depression and recurrence.
Investigators in the report suggest it is “premature to conclude that vitamin D status is related to the occurrence of depression. Additional prospective studies of this relationship are essential.”
While the exact relationship between mood disorders, chronic muscle pain and vitamin D deficiency has not be clearly established, evidence suggests that patients with chronic muscle pain, anxiety or depression should at least consider testing their vitamin D levels and supplementing if they are deficient.
Armstrong DJ, Meenagh GK, Bickle I, Lee AS, Curran ES, Finch MB, “Vitamin D deficiency is associated with anxiety and depression in fibromyalgia,” Clinical Rheumatology,2007 Apr.
An Pan, Ling Lu, Oscar H. Franco, Zhijie Yu, Huaixing Li, Xu Lin. “Association between depressive symptoms and 25-hydroxyvitamin D in middle-aged and elderly Chinese., “ Journal of Affective Disorders, 2009.
University of Warwick (2009, March 18). Vitamin D May Not Be The Answer To Feeling SAD. ScienceDaily. Retrieved March 3, 2010.
Bertone-Johnson ER, “Vitamin D and the occurrence of depression: causal association or circumstantial evidence?” Nutritional Review, 2009 Aug.