Vitamin D
Vitamin D is a hormone created by the body when skin is exposed to ultraviolet rays in sunlight. It is found naturally in a small number of foods and can also be taken as a fat-soluble dietary supplement.
Vitamin D at a glance
Vitamin D is a hormone that is created by the body with ultraviolet B (UVB) exposure from the sun. It can also be taken as a fat-soluble supplement in either softgel or liquid form and is found naturally in some foods.
Some research has found that vitamin D in the body reaches an optimum level regarding cancer risk starting at 20 ng/mL and may have an upper limit below 40 ng/mL for men. Higher levels than that are not always better and may even carry risks. Upper limits of optimal levels are unknown for women. Blood levels below 20 ng/mL are considered deficient in vitamin D.
Optimal vitamin D blood levels are linked to better survival, better conditions—body terrainthe internal conditions of your body, including nutritional status, fitness, blood sugar balance, hormone balance, inflammation and more factors—that are linked to better cancer outcomes, and lower risk of cancer. Optimal levels are also linked to fewer symptoms or less severe symptoms of some side effects common during cancer treatment. Vitamin D supplementation among people who have low blood levels shows benefits.
Use of some chemotherapy drugs is linked to lower plasma levels of vitamin D. Other drugs are also linked to low vitamin D levels, such as H2 blockers and rosuvastatin.1Gao Y, Shimizu M, Yamada S, Ozaki Y, Aso T. The effects of chemotherapy including cisplatin on vitamin D metabolism. Endocrine Journal. 1993 Dec;40(6):737-42; Fakih MG, Trump DL et al. Chemotherapy is linked to severe vitamin D deficiency in patients with colorectal cancer. International Journal of Colorectal Disease. 2009 Feb;24(2):219-24; Jacot W, Pouderoux S et al. Increased prevalence of vitamin D insufficiency in patients with breast cancer after neoadjuvant chemotherapy. Breast Cancer Research and Treatment. 2012 Jul;134(2):709-17. You might want to have your vitamin D levels checked before, during, and after using chemotherapy. If your levels are low before starting chemotherapy, talk with your doctor about using vitamin D supplements.
CancerChoices ratings for vitamin D
We rate vitamin D on seven attributes, with 0 the lowest rating and 5 the highest. We rate the strength of the evidence supporting the use of vitamin D for a medical benefit, such as improving treatment outcomes or managing side effects.
See how we evaluate and rate complementary therapies ›
Improving treatment outcomes
See MoreGood evidence of benefit
- Good evidencesignificant effects in one large or several mid-sized and well-designed clinical studies (randomized controlled trials (RCTs) with an appropriate placebo or other strong comparison control or observational studies that control for confounds) (this is the CancerChoices definition; other researchers and studies may define this differently) of moderately better cancer-specific survival among people with cancer with high vitamin D levels
- Good evidence of lower mortality, less cancer progression, and better rates of pathologic complete responsethe lack of any sign of cancer in biopsy samples taken after cancer treatment is completed among people with breast cancer with higher 25(OH)D levels
- Good evidence of lower mortality among people with colorectal cancer with the highest 25(OH)D levels
- Good evidence of less cancer progression and lower mortality among people with blood cancers with higher 25(OH)D levels
Modest evidence of benefit
- Modest evidencesignificant effects in at least three small but well-designed randomized controlled trials (RCTs), or one or more well-designed, mid-sized clinical studies of reasonably good quality (RCTs or observational studies), or several small studies aggregated into a meta-analysis (this is the CancerChoices definition; other researchers and studies may define this differently) of lower overall mortality among people with cancer taking vitamin D supplements
- Modest evidence of better survival, less progression, and fewer adverse cancer outcomes among people with colorectal cancer treated with vitamin D
- Modest evidence of higher mortality and more advanced cancer among people with stomach cancer or liver cancer with low 25(OH)D levels
- Modest evidence of lower mortality and relapse among people with stage 1–3 digestive tract cancers treated with vitamin D, especially among people with 25(OH)D levels under 40 ng/mL or with suppressed immune function
- Modest evidence of substantially better 5-year relapse-free and overall survival among people with poorly differentiated adenocarcinoma taking vitamin D3 after surgery
- Modest evidence of slightly better survival among people with head and neck cancer with high vitamin D intake
- Modest evidence of better overall and relapse-free survival among people with lung cancer taking vitamin D
- Modest evidence of higher overall mortality among people with skin cancer with low 25(OH)D levels
- Modest evidence of slightly longer survival among people with ovarian cancer with higher 25(OH)D levels at diagnosis, but no evidence of an effectoverall, one or more studies did not demonstrate that a treatment or intervention led to an expected outcome; this does not always mean that there is no effect in clinical practice, but that the studies may have been underpowered (too few participants) or poorly designed. Larger, well-designed studies provide more confidence in making assessments. on progression-free survivalthe time during and after treatment of a disease that a patient lives without disease progression (worsening) after treatment
- Modest evidence of lower mortality among people with pancreatic cancer with higher 25(OH)D levels
- Modest evidence of lower mortality among people with prostate cancer with higher vitamin D levels
Preliminary evidence of benefit
- Preliminary evidencesignificant effects in small or poorly designed clinical studies OR conflicting results in adequate studies but a preponderance of evidence of an effect (this is the CancerChoices definition; other researchers and studies may define this differently) of higher objective response rate and better progression-free survival during anti-PD-1 immunotherapy among people with advanced melanoma with normal baseline vitamin D levels or a normal level obtained with supplementation of better survival among people with breast cancer taking vitamin D supplements
- Preliminary evidence of less tumor blood vessel formation (angiogenesis) during tamoxifen treatment among premenopausal women, but varied results for postmenopausal women treated with vitamin D
- Preliminary evidence of moderately lower overall mortality but not cancer-specific mortality among people with renal cell carcinoma with higher 25(OH)D3 levels
- Preliminary evidence of better 5-year relapse-free survival and overall survival among people with both early stage lung adenocarcinoma and low 25(OH)D levels treated with vitamin D
- Preliminary evidence of lower risk of advanced tumors at diagnosis among people with melanoma with higher 25(OH)D3 level
- Preliminary and conflicting evidence of lower progression among people with melanoma with higher 25(OH)D levels in a combined analysis of studies
- Preliminary evidence of lower risk of relapse among people with melanoma with tumor thickness 0.75 mm or more with increases in 25(OH)D levels
No evidence of an effect
- No evidence of an effectoverall, one or more studies did not demonstrate that a treatment or intervention led to an expected outcome; this does not always mean that there is no effect in clinical practice, but that the studies may have been underpowered (too few participants) or poorly designed. Larger, well-designed studies provide more confidence in making assessments. on relapse among people with cancer using vitamin D supplements after diagnosis in a combined analysis of studies
- No evidence of an effect on markers of tumor proliferation or cell death in primary breast cancer cells from newly diagnosed people treated with 40,000 IU vitamin D in a small study
- No evidence of an effect on survival at 24 months after surgery among people with esophageal cancer taking vitamin D supplements in an observational study
- No evidence of an effect on cancer progression or mortality among people with head and neck cancer with higher 25(OH)D levels in a combined analysis of 2 studies
Optimizing your body terrain
See MoreGood or strong evidence of benefit
- Good evidencesignificant effects in one large or several mid-sized and well-designed clinical studies (randomized controlled trials (RCTs) with an appropriate placebo or other strong comparison control or observational studies that control for confounds) (this is the CancerChoices definition; other researchers and studies may define this differently) of higher risk of type 2 diabetes among people with lower 25(OH)D levels
- Good evidence of better markers of glycemic control and lower risk of insulin resistance among people without diabetes with higher 25(OH)D levels
- Good evidence of higher markers of inflammation among people with low 25(OH)D levels, typically below 10 ng/mL
- Strong evidenceconsistent, significant effects in several large (or at least one very large) well designed clinical studies or at least two meta-analyses of clinical studies of moderate or better quality (or one large meta-analysis) finding similar results (this is the CancerChoices definition; other researchers and studies may define this differently) of lower markers of inflammation among people treated with vitamin D
- Strong evidence of lower markers of oxidative stress among people, mostly with polycystic ovary syndrome, treated with vitamin D
- Good evidence of a link between overweight or larger waist circumference and lower 25(OH)D levels
Modest evidence of benefit
- Modest evidencesignificant effects in at least three small but well-designed randomized controlled trials (RCTs), or one or more well-designed, mid-sized clinical studies of reasonably good quality (RCTs or observational studies), or several small studies aggregated into a meta-analysis (this is the CancerChoices definition; other researchers and studies may define this differently) of lower fasting glucose among women with polycystic ovary syndrome treated with vitamin D
- Modest evidence of lower insulin resistance and higher insulin sensitivity among people treated with vitamin D
- Modest evidence of a slightly lower risk of type 2 diabetes among women with the highest vitamin D intake from supplements
- Modest evidence of a link between metabolic health and 25(OH)D levels among people with obesity
Preliminary evidence of benefit
- Preliminary evidencesignificant effects in small or poorly designed clinical studies OR conflicting results in adequate studies but a preponderance of evidence of an effect (this is the CancerChoices definition; other researchers and studies may define this differently) of higher insulin sensitivity and better blood glucose levels among people at risk for type 2 diabetes with higher 25(OH)D levels
- Preliminary evidence of lower 25(OH)D levels among people with diabetes
- Preliminary evidence of lower insulin resistance (HOMA) and better insulin sensitivity among people with diabetes or insulin resistance treated with vitamin D3
- Preliminary evidence of higher incidence of early onset of menstruation (menarche) among girls with low 25(OH)D levels
- Preliminary (conflicting) evidence of better balance of some sex hormones among people with imbalances treated with vitamin D
- Preliminary evidence of a substantial increase in leptin, which inhibits hunger responses, among people with type 2 diabetes treated with vitamin D
- Preliminary evidence of balanced immune function among people with higher vitamin D levels
- Preliminary evidence of balanced immune function among people treated with vitamin D
- Preliminary evidence of lower levels of a signaling protein related to the formation of new blood vessels among women with polycystic ovary syndrome treated with vitamin D
No evidence of an effect
- No evidence of an effectoverall, one or more studies did not demonstrate that a treatment or intervention led to an expected outcome; this does not always mean that there is no effect in clinical practice, but that the studies may have been underpowered (too few participants) or poorly designed. Larger, well-designed studies provide more confidence in making assessments. on body weight among postmenopausal women treated with vitamin D in a small study
Managing side effects and promoting wellness
See MoreModest evidence of benefit
- Modest evidencesignificant effects in at least three small but well-designed randomized controlled trials (RCTs), or one or more well-designed, mid-sized clinical studies of reasonably good quality (RCTs or observational studies), or several small studies aggregated into a meta-analysis (this is the CancerChoices definition; other researchers and studies may define this differently) of a link between lower 25(OH)D levels and more chemotherapy-induced peripheral neuropathy (CIPN) among people with cancer
- Modest evidence of lower pain during hormone therapy among people treated with vitamin D, and especially among people starting with lower 25(OH)D levels
Preliminary evidence of benefit
- Preliminary evidencesignificant effects in small or poorly designed clinical studies OR conflicting results in adequate studies but a preponderance of evidence of an effect (this is the CancerChoices definition; other researchers and studies may define this differently) of better muscle function among people with prostate cancer treated with vitamin D
- Preliminary evidence of less loss of bone mineral density during hormone therapy among people treated with high amounts of vitamin D
- Preliminary evidence of less fatigue among people with advanced cancer treated with vitamin D
- Preliminary evidence of substantially less oral mucositis during radiotherapy among people with head and neck cancer treated with a topical oral vitamin D gel
- Preliminary evidence of less opioid use among people with advanced cancer with 25(OH)D levels less than 20 ng/mL treated with vitamin D
- Preliminary evidence of less vaginal atrophy during tamoxifen treatment among women with breast cancer treated with vaginal vitamin D suppositories
- Preliminary evidence of higher severity of radiation-induced acute proctitis among people with vitamin D deficiency
No evidence of an effect
- No evidence of an effectoverall, one or more studies did not demonstrate that a treatment or intervention led to an expected outcome; this does not always mean that there is no effect in clinical practice, but that the studies may have been underpowered (too few participants) or poorly designed. Larger, well-designed studies provide more confidence in making assessments. on pain after brain tumor surgery among people with vitamin D serum levels of 20 ng/dL or lower treated with vitamin D before surgery in a small study
Reducing cancer risk
See MoreEvidence of benefit with higher levels or intake or worse outcomes with lower levels
Good evidence
- Good evidencesignificant effects in one large or several mid-sized and well-designed clinical studies (randomized controlled trials (RCTs) with an appropriate placebo or other strong comparison control or observational studies that control for confounds) (this is the CancerChoices definition; other researchers and studies may define this differently) of lower cancer mortality among people without cancer at baseline with higher 25(OH)D levels
- Strong evidenceconsistent, significant effects in several large (or at least one very large) well designed clinical studies or at least two meta-analyses of clinical studies of moderate or better quality (or one large meta-analysis) finding similar results (this is the CancerChoices definition; other researchers and studies may define this differently) of slightly lower cancer mortality among people without cancer at baseline taking vitamin D supplements
- Good evidence of lower risk of metastatic or fatal cancer among people without cancer and not overweight or obese at baseline treated with vitamin D3
- Good evidence of lower risk of recurrence among people with breast cancer with higher 25(OH)D levels at diagnosis
- Good evidence of higher risk of breast cancer among people with low 25(OH)D levels, and especially among premenopausal women
- Good evidence of lower risk of colorectal cancer among people with higher 25(OH)D levels
- Good evidence of lower risk of colorectal cancer among people with higher total vitamin D intake
- Good evidence of slightly lower risk of colorectal cancer among people taking vitamin D supplements
- Good evidence of higher risk of liver cancer among people with low levels of vitamin D
- Good evidence of lower risk of head and neck cancer among people with high 25(OH)D levels
- Good evidence of lower risk of head and neck cancer among people with high intake of vitamin D in their diet
- Good evidence of lower risk of lung cancer among people with higher 25(OH)D levels, although very high levels—above about 34 ng/mL—are linked to increased risk
- Good evidence of higher risk of prostate cancer among men with low 25(OH)D levels
- Good evidence of higher risk of thyroid cancer among people with low levels of vitamin D
Modest evidence
- Modest evidencesignificant effects in at least three small but well-designed randomized controlled trials (RCTs), or one or more well-designed, mid-sized clinical studies of reasonably good quality (RCTs or observational studies), or several small studies aggregated into a meta-analysis (this is the CancerChoices definition; other researchers and studies may define this differently) of lower risk of cancer among healthy adults aged 70 years or older taking vitamin D supplements
- Modest evidence of moderately lower risk of recurrence among people taking vitamin D supplements after a diagnosis of ER positive but not ER negative breast cancer
- Modest evidence of slightly lower risk of CRC as a whole with each increase of 100 IU dietary vitamin D intake
- Modest evidence of lower risk of renal cell carcinoma among people, especially women, with the highest circulating vitamin D levels
- Modest evidence of lower risk of renal cell carcinoma among people, especially women, with the highest dietary vitamin D intake
- Modest evidence of lower lung-cancer mortality among people without cancer at baseline with higher 25(OH)D levels; see also indications that very high levels may increase mortality in Safety and precautions ›
- Modest evidence of slightly lower risk of lung cancer among people with the highest vitamin D intake from either diet or supplements
- Modest evidence of lower risk of recurrence among people with lymphoma with the highest 25(OH)D levels at diagnosis
- Modest evidence of lower risk of non-Hodgkin lymphoma among people with high levels of exposure to sunlight/ultraviolet radiation
- Modest evidence of lower risk of melanoma recurrence among people with higher 25(OH)D levels
- Modest evidence of a link between vitamin D deficiency and melanoma incidence/stage
- Modest evidence of slightly lower risk of ovarian cancer among people with higher circulating vitamin D levels
- Modest evidence of lower risk of aggressive prostate cancer among African-Americans or people with low body mass index taking the highest levels of vitamin D supplements, but not among other people
Preliminary evidence of benefit
- Preliminary evidencesignificant effects in small or poorly designed clinical studies OR conflicting results in adequate studies but a preponderance of evidence of an effect (this is the CancerChoices definition; other researchers and studies may define this differently) of slightly lower risk of breast cancer among people with higher vitamin D intake
- Preliminary evidence of lower risk of recurrence after surgery among people with esophageal cancer taking vitamin D supplements
- Preliminary evidence of lower risk of recurrence among women with grade 2 or 3 cervical intraepithelial neoplasia treated with vitamin D
- Preliminary evidence of lower risk of recurrence among people with head and neck cancer with higher total (diet and supplement) intake of vitamin D
No evidence of an effect
- No evidence of an effectoverall, one or more studies did not demonstrate that a treatment or intervention led to an expected outcome; this does not always mean that there is no effect in clinical practice, but that the studies may have been underpowered (too few participants) or poorly designed. Larger, well-designed studies provide more confidence in making assessments. on risk of adenoma after colorectal adenoma surgery among people treated with vitamin D3 in a large study
- No evidence of an effect of 25(OH)D levels on risk of non-Hodgkin lymphoma in a combined analysis of studie
- No evidence of an effect on risk of non-Hodgkin lymphoma among people with higher levels of dietary vitamin D intake in a combined analysis of studies
- No evidence of an effect on risk of pancreatic cancer among people with higher 25(OH)D levels in a combined analysis of studies
- No evidence of an effect at 3 months on free or total PSA among healthy men taking vitamin D in a small study
Use by integrative oncology experts
See More- Widely used by our program sources
- Mentioned in two practice guidelines with no recommendation for use for treating pain due to insufficient evidence
- No mention in clinical practice guidelines for other medical benefits
Safety
See More- Increased risk of some types of cancer with higher than normal 25(OH)D levels, especially higher than 40 ng/mL
- A few rare adverse reactions and drug interactions are noted with high 25(OH)D levels, especially at or above 40 ng/mL.
- Vitamin D toxicity and overdose are possible when taking high doses of supplements. Medical supervision is advised.
- Individuals with disorders of calcium metabolism, gastrointestinal disease, kidney disease, heart disease, or liver disease should consult a physician before using vitamin D supplements.
Affordability and access
See More- Widely available without restriction
- Generally inexpensive (less than $500 US/year)
Keep reading about vitamin D
Authors
Ms. Hepp is a researcher and communicator who has been writing and editing educational content on varied health topics for more than 20 years. She serves as lead researcher and writer for CancerChoices and also served as the first program manager. Her graduate work in research and cognitive psychology, her master’s degree in instructional design, and her certificate in web design have all guided her in writing and presenting information for a wide variety of audiences and uses. Nancy’s service as faculty development coordinator in the Department of Family Medicine at Wright State University also provided experience in medical research, plus insights into medical education and medical care from the professional’s perspective.
Dr. Ryan served as a research associate for CancerChoices. She is a licensed and board certified naturopathic physician and acupuncturist in Oregon. Dr. Ryan is the founder of Gentle Natural Wellness, a clinic specializing in bridging classical Chinese medicine with naturopathic medicine to provide individualized, compassionate care for people in the community. A Doctorate of Naturopathic Medicine and Master of Science in Oriental Medicine with honors from the National University of Natural Medicine, research in medical anthropology at the University of Hawai’i and George Mason University, language and culture programs at Obirin University (Tokyo) and Sogang University (Seoul), and studies of Chinese herbal medicine and qigong in China have provided a diverse background that has helped form a foundation for her community health and healing path.
Reviewer
Laura Pole is senior clinical consultant for CancerChoices. Laura is an oncology clinical nurse specialist who has been providing integrative oncology clinical care, navigation, consultation, and education services for over 40 years. She is the co-creator and co-coordinator of the Integrative Oncology Navigation Training at Smith Center for Healing and the Arts in Washington, DC. Laura also manages the “Media Watch Cancer News That You Can Use” listserv for Smith Center/Commonweal. In her role as a palliative care educator and consultant, Laura has served as statewide Respecting Choices Faculty for the Virginia POST (Physician Orders for Scope of Treatment) Collaborative as well as provided statewide professional education on palliative and end-of-life care for the Virginia Association for Hospices and Palliative Care.
For CancerChoices, Laura curates content and research, networks with clinical and organizational partners, brings awareness and education of integrative oncology at professional and patient conferences and programs, and translates research into information relevant to the patient experience as well as clinical practice.
Laura sees her work with CancerChoices as a perfect alignment of all her passions, knowledge and skills in integrative oncology care. She is honored to serve you.
Last update: December 12, 2024
Last full literature review: February 2022
CancerChoices provides information about integrative in cancer care, a patient-centered approach combining the best of conventional care, self care and evidence-informed complementary care in an integrated plan cancer care. We review complementaryin cancer care, complementary care involves the use of therapies intended to enhance or add to standard conventional treatments; examples include supplements, mind-body approaches such as yoga or psychosocial therapy, and acupuncture therapies and self-care lifestyle actions and behaviors that may impact cancer outcomes; examples include eating health-promoting foods, limiting alcohol, increasing physical activity, and managing stress practices to help patients and professionals explore and integrate the best combination of conventionalthe cancer care offered by conventionally trained physicians and most hospitals; examples are chemotherapy, surgery, and radiotherapy and complementary therapies and practices for each person.
Our staff have no financial conflicts of interest to declare. We receive no funds from any manufacturers or retailers gaining financial profit by promoting or discouraging therapies mentioned on this site.
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References[+]
| 1 | Gao Y, Shimizu M, Yamada S, Ozaki Y, Aso T. The effects of chemotherapy including cisplatin on vitamin D metabolism. Endocrine Journal. 1993 Dec;40(6):737-42; Fakih MG, Trump DL et al. Chemotherapy is linked to severe vitamin D deficiency in patients with colorectal cancer. International Journal of Colorectal Disease. 2009 Feb;24(2):219-24; Jacot W, Pouderoux S et al. Increased prevalence of vitamin D insufficiency in patients with breast cancer after neoadjuvant chemotherapy. Breast Cancer Research and Treatment. 2012 Jul;134(2):709-17. |
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