VITAMIN D
In a 1998 controlled experiment, Australian researchers found that vitamin D (400 and 800 IU), significantly enhanced positive affect when given to healthy individuals. Forty-four subjects were given 400 IU cholecalciferol, 800 IU cholecalciferol, or placebo for 5 days during late winter in a random double-blind study. Results on a self-report measure showed that vitamin D3 enhanced positive affect a full standard deviation and there was some evidence of a reduction in negative affect. The authors concluded: “vitamin D3 deficiency provides a compelling and parsimonious explanation for seasonal variations in mood” (Landsdowne & Provost, 1998).
In another study in 1999, the vitamin D scientist, Bruce Hollis, teamed up with Michael Gloth and Wasif Alam to find that 100,000 IU of vitamin D given as a one time oral dose improved depression scales better than light therapy in a small group of patients with seasonal affective disorder. All subjects in the vitamin D group improved in all measures and, more importantly, improvement in 25(OH)D levels levels was significantly associated with the degree of improvement (Gloth et al. 1999).
According to the Vitamin D Council:
To further strengthen the case that vitamin D deficiency causes some cases of depression, evidence should exist that the incidence of depression has increased over the last century. During that time, humans have reduced their sunlight exposure via urbanization (tall buildings and pollution reduce UVB ), industrialization (working inside reduces UVB exposure), cars (glass totally blocks UVB), clothes (even light clothing blocks UVB), sunblock and misguided medical advice to never let sunlight strike you unprotected skin.All these factors contribute to reduce circulating 25(OH)D levels.
Klerman and Weissman’s claim that major depression has increased dramatically over the last 80 years is one of the most famous (and controversial) findings in modern psychiatry. Something called recall bias (a type of selective remembering) may explain some of the reported increase, but does it explain it all?
If you suffer from depression, get your 25(OH)D level checked and, if it is lower than 35 ng/mL (87 nM/L), you are vitamin D deficient and should begin treatment. If you are not depressed, get your 25(OH)D level checked anyway. If it is lower than 35 ng/mL (87 nM/L), you are vitamin D deficient and should begin treatment.
Recommended intake is up to 5,000 IU per day of vitamin D through exposure to sunshine and/or supplementation. See this article on vitamin D to learn to calculate how much vitamin D is produced given a certain amount of exposure to sunlight, and to learn more about vitamin D supplementation. It is important to remember that D works synergistically with A & K2, so if you increase your intake of D you must also increase your intake of A & K2 to avoid D toxicity.
thehealthyskeptic.org |
