Date of Award


Degree Type


Degree Name

Master of Science in Biomedical Sciences




Depression, or major depressive disorder, has affected how people think, feel, and behave. As well as psychological problems, depression has also been a comorbid factor in other emotional and physiological disorders. The actual cause of depression is unknown. Researchers have worked to understand the connections and conditions a person may experience for depression to develop. One commonly researched path to depression is vitamin deficiency. A variety of vitamins like B6, B12, folate, and vitamin D have been linked extensively to depression as a possible cause. A continuation of research expands into how a deficiency of these vitamins causes depression. Low levels of these vitamins are associated with taking birth control and other medication, nutrition, diet, and disorders. Several research studies have led to understanding biological pathways and determined that vitamins such as B6, B12, and folate share a common pathway, homocysteine metabolism. Reduced levels of these vitamins have caused an increased level of homocysteine. An increased concentration of homocysteine is associated with depression, cerebrovascular disease, and monoamine neurotransmitters.

A combination of these effects has led to the creation of a hypothesis: high homocysteine levels can cause cerebral vascular disease and neurotransmitter deficiency resulting in a depressed mood. In this paper, depression is explored through the lens of homocysteine metabolism, the cause of the pathway’s dysfunction, and if vitamin D is related. Additionally, treatment by vitamin supplementation will also be examined.

Included in

Neurosciences Commons