Seasonal Affective Disorder (... : Supplements

Vitamin D is found in numerous dietary sources such as fish, eggs, fortified milk, and cod liver oil. The sun is also a significant contributor to our daily production of vitamin D, and as little as 10 minutes of exposure is thought to be enough to prevent deficiencies. The term "vitamin D" refers to several different forms of this vitamin. Two forms are important in humans: ergocalciferol (vitamin D2) and cholecalciferol (vitamin D3). Vitamin D2 is synthesized by plants. Vitamin D3 is synthesized by humans in the skin when it is exposed to ultraviolet-B (UVB) rays from sunlight or the diet. The major biologic function of vitamin D is to maintain normal blood levels of calcium and phosphorus. Vitamin D aids in the absorption of calcium, helping to form and maintain strong bones. Recently, research also suggests vitamin D may provide protection from osteoporosis, hypertension, cancer, and several autoimmune diseases. Rickets and osteomalacia are classic vitamin D deficiency diseases. In children, vitamin D deficiency causes rickets, which results in skeletal deformities. In adults, vitamin D deficiency can lead to osteomalacia, which results in muscular weakness in addition to weak bones. People who are at a high risk for vitamin D deficiencies are the elderly, dark skinned, obese, exclusively breast-fed infants, and those who cover all exposed skin or use sunscreen whenever outside. Also, those who have fat malabsorption syndromes (e.g., cystic fibrosis) or inflammatory bowel disease (e.g., Crohn's disease) are at risk.

A vitamin D analog.

Ginkgo biloba has been used medicinally for thousands of years. Today, it is one of the top selling herbs in the United States. Ginkgo is used for the treatment of numerous conditions, many which are under scientific investigation. Available evidence demonstrates ginkgo's efficacy in the management of intermittent claudication, Alzheimer's/multi-infarct dementia, and "cerebral insufficiency" (a syndrome thought to be secondary to atherosclerotic disease, characterized by impaired concentration, confusion, decreased physical performance, fatigue, headache, dizziness, depression, and anxiety). Although not definitive, there is promising early evidence favoring use of ginkgo for memory enhancement in healthy subjects, altitude (mountain) sickness, symptoms of premenstrual syndrome (PMS), and reduction of chemotherapy-induced end-organ vascular damage. Although still controversial, a recent large trial has shifted the evidence against the use of ginkgo for tinnitus. The herb is generally well tolerated, but due to multiple case reports of bleeding, should be used cautiously in patients on anti-coagulant therapy, with known coagulopathy, or prior to some surgical or dental procedures.

Ginkgo biloba is an herbal remedy that has been utilized for thousands of years in China and elsewhere. It is obtained from the leaves and seeds of a plant that is commonly known as the maiden hair tree, believed to be the oldest living species of tree.

Ginkgo biloba , known as the maidenhair tree, is one of the oldest trees on Earth, once part of the flora of the Mesozoic period. The ginkgo tree is the only surviving species of the Ginkgoaceae family.

Ginkgo biloba , known as the maidenhair tree, is one of the oldest trees on Earth, once part of the flora of the Mesozoic period. The ginkgo tree is the only surviving species of the Ginkgoaceae family.

Melatonin is a hormone produced in the brain by the pineal gland, from the amino acid tryptophan. The synthesis and release of melatonin are stimulated by darkness and suppressed by light, suggesting the involvement of melatonin in circadian rhythm and regulation of diverse body functions. Levels of melatonin in the blood are highest prior to bedtime. Synthetic melatonin supplements have been used for a variety of medical conditions, most notably for disorders related to sleep. Melatonin possesses antioxidant activity, and many of its proposed therapeutic or preventive uses are based on this property. New drugs that block the effects of melatonin are in development, such as BMS-214778 or luzindole, and may have uses in various disorders.

Melatonin is a hormone produced naturally in the pineal gland at the base of the brain. It is important in regulating sleep, and may play a role in maintaining circadian rhythm, the body ' s natural time clock.

Extracts of Hypericum perforatum L. (St. John's wort) have been recommended traditionally for a wide range of medical conditions. The most common modern-day use of St. John's wort is the treatment of depression. Numerous studies report St. John's wort to be more effective than placebo and equally effective as tricyclic antidepressant drugs in the short-term treatment of mild-to-moderate major depression (1-3 months). It is not clear if St. John's wort is as effective as selective serotonin reuptake inhibitor (SSRI) antidepressants such as sertraline (Zoloft®). Recently, controversy has been raised by two high-quality trials of St. John's wort for major depression that did not show any benefits. However, due to problems with the designs of these studies, they cannot be considered definitive. Overall, the scientific evidence supports the effectiveness of St. John's wort in mild-to-moderate major depression. The evidence in severe major depression remains unclear. St. John's wort can cause many serious interactions with prescription drugs, herbs, or supplements. Therefore, people using any medications should consult their healthcare providers including their pharmacist prior to starting therapy.

Hypericum perforatum is the most medicinally important species of the Hypericum genus, commonly known as St. John ' s wort or Klamath weed.

St. John's wort is a perennial, yellow-flowering plant that grows in the wild throughout Europe and is now found also in North America.