Cholecalciferol, also known as vitamin D3, is a form of vitamin D often found in dietary supplements and vitamin D-fortified foods. Vitamin D is abundant in foods, but many Americans are deficient in this essential vitamin, according to a study published in 2011 in Nutrition Research. Therefore, taking cholecalciferol in supplement form may help prevent vitamin D deficiency.
Advantages for Bone Health

Vitamin D plays an important role in bone growth in children and healthy bone maintenance in adulthood. The Office of Dietary Supplements notes that vitamin D aids in calcium absorption and helps prevent osteoporosis, which can cause weak and brittle bones. Vitamin D deficiency in childhood can lead to a condition called rickets, which causes soft bones, skeletal deformities, bone pain, fractures, impaired growth and dental deformities, notes MedlinePlus.

Effects on Immune Function

Getting plenty of vitamin D helps keep your immune system strong. A review published in 2011 in the Journal of Investigative Medicine reports that vitamin D deficiency weakens your immune system and increases your susceptibility for infection. Therefore, authors of this review suggest that supplementing with vitamin D may be beneficial for people with autoimmune diseases. The recommended dietary allowance (RDA) for vitamin D is 15 to 20 micrograms daily for adults, according to the Institute of Medicine.

Importance for Cognitive Function

Vitamin D also plays a role in optimizing brain health and reduces your risk for developing cognitive impairment or dementia, according to a review published in 2012 in the Scandinavian Journal of Clinical and Laboratory Investigation. Authors of this review point out that brain tissue is full of vitamin D receptors, and vitamin D3 (cholecalciferol) may help protect against Alzheimer's disease because low vitamin D levels are associated with the disease.

Heart Disease Risk Reduction

Getting too little vitamin D may put you at a higher risk for developing heart disease. A study published in 2011 in The American Journal of Clinical Nutrition found that men with higher vitamin D intakes from food and supplements had lower risks for developing heart disease. However, this study did not find the same association between vitamin D and heart disease risks in women.

Effects on Mood

If you're deficient in vitamin D and suffering from depression, taking a vitamin D3 supplement may help boost your mood. A study published in 2014 in Molecular Psychiatry found that study participants with depression had low levels of vitamin D in their bodies. Furthermore, depressive symptoms were worse in people with the lowest vitamin D levels. Researchers who conducted this study note that vitamin D supplementation may be a cost-effective way to help treat people with depressive disorders.

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