Vitamin D3 Benefits, Dosage, and Side Effects

By some estimates, one billion people worldwide have vitamin D deficiency or insufficiency.[1] Deficiency is an issue as serum vitamin D levels impact our biochemistry and numerous body systems (primarily through calcitriol, the metabolic product of vitamin D). The recommended form of vitamin D is often vitamin D3 as it appears to support serum vitamin D levels for a longer period of time compared to vitamin D2 [21]. 

Vitamin D3 Benefits

The role of vitamin D in good health continues to expand as the knowledge of this vitamin’s effects on different body systems grows. Research now suggests that optimal serum levels of vitamin D support normal cell differentiation,[3,7] cardiovascular health,[2,3] normal immune function,[8] good balance,[2] healthy mood,[9] normal fetal development,[10] neuronal growth and neurodevelopment,[2,3,10,11] healthy glucose metabolism,[2,3] musculoskeletal comfort,[2,3] periodontal health,[12] and normal intestinal immune responses.*[8]

Additional areas of research that have gained momentum over the past several years concern the relationship of vitamin D deficiency or insufficiency to changes in cellular proliferation, changes in fetal brain development, and mental health.[7,10,13-15] Evidence is also mounting that vitamin D supplementation may provide key immune support.*[16-19]

Vitamin D3 and Bone Health

The body needs vitamin D to absorb calcium, and the importance of vitamin D in skeletal health and bone density is well established. Although bone density is most often associated with calcium intakes, insufficient vitamin D negatively affects calcium absorption.[3] Without adequate absorption, the body must take calcium from its stores in the skeleton, which weakens existing bone and prevents the formation of strong, new bone. Clinical research shows that taking vitamin D orally with calcium supplements can support healthy bone turnover[4-6], and adequate calcium and vitamin D throughout life—as part of a well-balanced diet—may reduce the risk of osteoporosis.*

Vitamin D3 Dosage

It's commonly recommended to adjust vitamin D3 dose based on sun exposure, vitamin D blood levels, and time of the year.*

Here's what a lot of supplement companies won't tell you: Generally, folks don't need to take a vitamin D supplement if they are in the sun for 15-20 minutes most days between April and October, or if they have a normal vitamin D blood level (we generally aim for levels above 40, even though most labs consider 20 or 30 to be normal). *

Based on these considerations, common dosing is:

• 2,000 IU daily when there is some sun exposure and blood levels are low normal.*
• 5,000 IU daily when there is no or very little sun exposure (i.e., during the winter months) and/or blood levels are very low.*

Vitamin D3 Side Effects

Vitamin D toxicity is a rare, but serious condition that can be caused by taking high doses of vitamin D supplements over an extended period of time. Research in this area has cited toxicity when individuals take 60,000 IU daily over several months. Toxicity is associated with a buildup of calcium in the blood and a variety of symptoms come along with it (e.g., vomiting, fatigue, frequent urination, formation of calcium stones).*

Important strategies to avoid toxicity include having your blood levels checked, working with a doctor before beginning a supplement, and avoiding excessive dosing unless it is part of a treatment plan that is monitored by your doctor.*

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Vitamin D3 Supplements at Fullscript

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Ortho Molecular Products'

Vitamin D 5000 IU*

*Note: Some of the supplements discussed in this article can cause side effects, but many people tolerate them much better than prescription medications. They are generally considered safe, however, they should not be started without your doctor’s knowledge and supervision. If you are taking medication already, be sure to talk with your doctor before adding any of these items. If you are considering going off medication, remember never to stop your medication suddenly—always consult with your doctor about how to safely taper off any psychiatric medication. See terms.

**These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

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SAD is better prevented than treated. If prevention strategies start by October, SAD can be prevented for many individuals. There are four strategies that I usually recommend for prevention. Put them into practice and you can improve your chances of getting through the winter intact. Read more.

SOURCES

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