A deficiency of any vitamin will have an ill effect on our health. The lack of vitamin D has been linked to diabetes, some types of cancer, heart disease, and now depression. It is not known whether the link is causative, but depressed people have reduced their symptoms by restocking their body’s supply of vitamin D.
Our body creates its own vitamin D when exposed to sunlight. Ultraviolet rays change a skin biochemical intovitamin D that is subsequently morphed into the hormone calcitriol, the vitamin’s active form. We also get some of this vitamin from food.
There are small amounts of vitamin D in salmon, tuna, mackerel, egg yolks, beef liver, and cheese, and it is added to some foods such as milk. Vitamin D was first added to milk when its importance for strong bones and calcium regulation was determined.
Vitamin D and Our Brain
Our brain has vitamin D receptors in the hippocampus (learning and memory area) and throughout our central nervous system. Receptors are like outlets that the vitamin D can plug into. The presence of receptors suggests the necessity of vitamin D for emotional and behavioral regulation.
Vitamin D is also involved with nerve growth and neurotransmitter synthesis by deactivating enzymes in the cerebrospinal fluid and brain. Evidence of this are the brains of animals born to mother’s deficient in vitamin D. The young animals show developmental neural abnormalities.
Clinical studies have correlated low levels of vitamin D not only to depression, but to cognitive impairment. A deficiency is related to slower processing of information, and lower scores on mental tests, in older adults. Research is being done to discover if high levels of vitamin D can restore cognitive function lost to age or illness.
Vitamin D and Depression
Increased vitamin D is known to raise our gray matter’s serotonin levels. In that sense it works like a prescription antidepressant. It may also reduce inflammation and protect our neurons by slowing production of the protein cytokine, an inflammatory agent suspected in the onset of depression.
Though depressive symptoms may be a result of vitamin deficiency, they may also be partly the cause.
Sometimes symptoms of depression result in isolation and not enough time in the sun. Depressed people may also have suppressed appetites and not eat enough foods that provide the vitamin, or not have the inclination or energy to shop for groceries.
Get Your Dzzz!
Sun exposure of 15 to 30 minutes, three times each week, allows the body to synthesize a healthy amount of vitamin D. There is currently some paranoia about sun exposure and warranted or not, may be contributing to deficiencies of the sunshine vitamin.
The currently recommended daily intake of vitamin D, from The Institute of Medicine, is 600 IU for ages one to seventy, and 800 IU for those beyond 70. Other experts recommend twice those amounts. Your doctor can test yourvitamin D level and determine how much supplemental vitamin D you might need.