Vitamin D Supplementation and Cancer Prevention

Thomas L. Lenz, PharmD, MA, PAPHS


Am J Lifestyle Med. 2009;3(5):365-368. 

In This Article

Abstract and Introduction


It is estimated that approximately 1 billion people worldwide have blood concentrations of vitamin D that are considered suboptimal. Much research has been conducted over the past 30 years linking low vitamin D serum concentrations to both skeletal and nonskeletal conditions, including several types of cancers, cardiovascular disease, diabetes, upper respiratory tract infections, all-cause mortality, and many others. Several observational studies and a few prospectively randomized controlled trials have demonstrated that adequate levels of vitamin D can decrease the risk and improve survival rates for several types of cancers including breast, rectum, ovary, prostate, stomach, bladder, esophagus, kidney, lung, pancreas, uterus, non-Hodgkin lymphoma, and multiple myeloma. Individuals with serum vitamin D concentrations less than 20 ng/mL are considered most at risk, whereas those who achieve levels of 32 to 100 ng/mL are considered to have sufficient serum vitamin D concentrations. Vitamin D can be obtained from exposure to the sun, through dietary intake, and via supplementation. Obtaining a total of approximately 4000 IU/d of vitamin D3 from all sources has been shown to achieve serum concentrations considered to be in the sufficient range. Most individuals will require a dietary supplement of 2000 IU/d of vitamin D3 to achieve sufficient levels as up to 10 000 IU/d is considered safe. Vitamin D3 is available as an over-the-counter product at most pharmacies and is relatively inexpensive, especially when compared with the demonstrated benefits.


It is well known that a causal link exists between severe vitamin D deficiency and rickets in children and the bone disease osteomalacia in adults. It is also well known that vitamin D insufficiency is associated with osteoporosis, a decrease in muscular strength, and increased fall risk. It is less well known, however, that a low serum concentration of vitamin D is also associated with several other diseases and conditions.

It is estimated that 1 billion people worldwide have vitamin D deficiency or insuffiency.[1] Patients ranging from children to elderly are affected by vitamin D deficiency. One study showed that 48% of white preadolescent girls had deficient blood levels of vitamin D.[2] Another study reported that more than half of postmenopausal women taking medication for osteoporosis had suboptimal blood levels of vitamin D.[3] Several other studies report that from 40% to 100% of community-living elderly men and women in both the United States and Europe have deficient levels of vitamin D.[1] The estimated cost to our society of vitamin D deficiency is reported to be between $100 and $200 billion per year.[4]

The recent number of medical publications on the topic of vitamin D is astounding. A PubMed search of the previous 10 years alone using the term "vitamin D" resulted in 17 399 publication displays. The newly appreciated associations between low vitamin D levels and diseases include glucose intolerance, diabetes mellitus, metabolic syndrome, cardiovascular disease, myocardial infarction, hypertension, obesity, heart failure, myopathy, inflammatory bowel disease, multiple sclerosis, psoriasis, tuberculosis, upper respiratory tract infections, polycystic ovarian syndrome, and even all-cause mortality.[5,6] In addition, a great deal of research has been conducted linking low vitamin D levels with several types of cancers. A follow-up PubMed search of the previous 10 years using the terms "vitamin D AND cancer" resulted in 2870 publication displays, of which two-thirds were published in the past 5 years. The purpose of this article is to briefly review the physiology behind vitamin D, provide an overview of key research linking vitamin D intake with decreased cancer risk, and present the current recommendations for vitamin D intake.


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