Newly released findings of a study done in Ireland show that older adults who do not get enough Vitamin D suffer from Depression 75% more often than adults who get the recommended daily amount.  Although research has long shown a link between Depression and vitamin D deficiency, few comprehensive studies over a significant time period have been conducted.

According to the National Institute of Health, more than 50% of humans worldwide do not get enough Vitamin D. The lack is associated with a number of health issues and a higher mortality rate.  In older people, lack of Vitamin D is also associated with an increased risk of falling.

There are Vitamin D receptors in the brain, although scientists still don’t know exactly how mood is affected. Some theorize that vitamin D affects monoamines like serotonin, which greatly influence mood. The more serotonin in the body, the less depressed a person will feel.

A New And More Thorough Examination Of Vitamin D Deficiency

Although other studies have been done, the Irish study is the first comprehensive study on the subject of Depression and Vitamin D, and it also factored in variables such as medication, cardiovascular disease, and physical activity.

The study was conducted by The Irish Longitudinal Study on Ageing (TILDA) at Trinity College Dublin. It looked at a lack of Vitamin D and how adults were affected by it four years later. The lack of Vitamin D is associated with diabetes, bone health, and inflammation. The findings of the study were published in the Journal of Post-Acute and Long-Term Care Medicine (JAMDA).

Most significantly, a lack of the vitamin was associated with a 75% increase in the risk of developing depression after a period of four years.

Vitamin D, The Sunshine Pill

Vitamin D is the only nutrient that the human body produces in response to sunlight. It’s absorbed into the skin. According to the National Institute of Health, natural sunlight is the best source of vitamin D for both children and adults. Doctors recommend that people spend a minimum of 15 minutes outside every day, on sunny days. As most people in industrialized countries have become less active outside, we have become more depressed. Walking the dog, gardening, washing the car, sunbathing (within reason) – all are actually good for the human body. So how does sunshine equate to happiness? We know that Vitamin D accessed from sunlight is more effective than Vitamin D in a supplement.

Food Sources of Vitamin D

However, there are plenty of dietary sources of Vitamin D as well.  Salmon is by far the best source, offering 12-18 units in standard three-ounce portions. Other fish like whitefish, sturgeon, trout, tuna, Tilapia, and swordfish also contain high amounts of Vitamin D.

Dairy products such as milk and yogurt are also good sources of Vitamin D. Vitamin D helps calcium to be utilized effectively by the body. In America, dairy is often fortified with extra Vitamin D, but that’s not true in Ireland or many other countries. The recommended daily intake for people under age 70 is 600 IU, and for those 70 and older it’s 800 IU daily.

The Irish study stopped short of determining if supplements that increased daily Vitamin D intake would significantly decrease depression.  Here in America, the National Institute of Health recommends taking supplements to lower the risks of many conditions, including heart disease, cancer, and autoimmune disease.

However, researchers also stress that although there seems to be a correlation between Vitamin D deficiency and Depression, more research needs to be done. Symptoms of Depression often develop slowly, over a period of years, and can be affected greatly by prescription medications such as corticosteroids.