Vitamin D3

Recommendation: Strongly in favor (Studies have shown that a Vitamin D can help to prevent and treat rickets)

Grade of Evidence: High level of evidence

Recomendation: Weakly in favor (There are some studies that show vitamin D may be able to help treat symptoms of Anorexia Nervosa. More studies are needed)

Grade of Evidence: Low level of evidence

Chronic Renal Failure [11, 12, 13, 14]:

Recommendation: Strongly in favor 

Grade of Evidence: Moderate level of evidence

Cystic Fibrosis [15, 16, 17]:

Recommendation: Weakly in favor (Early studies show vitamin D may be beneficial for those with CF. More studies needed)

Grade of Evidence: Low level of evidence

Familial Adenomatous Polyposis [1, 5, 7]:

Recommendation: Weakly in favor (Observational studies show that a higher intake of Vitamin D may help lower the risk of getting Familial Adenomatous Polyposis. However, clinical trials need to be completed to provide more reliable evidence.)

Grade of Evidence: Low level of evidence

Osteoporosis [1, 5, 7]:

Recommendation: Strongly in favor (Vitamin D may help to prevent osteoporosis in older people )

Grade of Evidence: High level of evidence

Prostate Cancer [1, 4, 5, 6, 7]:

Recommendation: Weakly in favor (Studies have shown that a higher intake of Vitamin D may help to treat symptoms of bone pain in patients with prostate cancer. However, these results are not fully reliable, and more studies are needed)

Grade of Evidence: Low level of evidence

Psoriasis [1, 5, 7]:

Recommendation: Strongly in favor (Studies have shown that a Vitamin D derivative may be effective in reducing the symptoms of psoriasis)

Grade of Evidence: High level of evidence

Osteoporosis [1, 5, 7]:

Recommendation: Strongly in favor (Studies have shown that a higher intake of vitamin D can reduce the risk of hip fractures among older people following falls. However these studies have had conflicting results, and more studies are needed.)

Grade of Evidence: High level of evidence

Colorectal Cancer [1, 4, 5, 6, 7]:

Recommendation: Weakly in favor (Studies have shown that a higher intake of Vitamin D may help to treat symptoms of bone pain in patients with colorectal cancer. However, these results are not fully reliable, and more studies are needed)

Grade of Evidence: Low level of evidence

* www.gradeworkinggroup.org 

References: 
1.  Ades T, Alteri R, Gansler T, Yeargin P, "Complete Guide to Complimentary & Alternative Cancer Therapies", American Cancer Society, Atlanta USA, 2009

2. http://onlinelibrary.wiley.com/o/cochrane/clsysrev/articles/CD006164/frame.html rickets 

3. http://www.ncbi.nlm.nih.gov/pubmed/10824056 rickets

4. http://informahealthcare.com/doi/abs/10.1185/030079908X253519 cancer

5. http://www.ncbi.nlm.nih.gov/pubmed/17556697 

6. http://www.ncbi.nlm.nih.gov/pubmed/18065602 cancer

7. http://www.nlm.nih.gov/medlineplus/vitamind.html

8. http://www.ncbi.nlm.nih.gov/pubmed/21632810

9. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3199303/

10. http://jcp.bmj.com/content/41/2/195

11. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3280034/

12. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2878736/

13. http://www.ncbi.nlm.nih.gov/pubmed/17293681/

14. http://www.ncbi.nlm.nih.gov/pubmed/15577113

15. http://www.ncbi.nlm.nih.gov/pubmed/24823922

16. http://www.hindawi.com/journals/ije/2010/218691/

17. http://www.ncbi.nlm.nih.gov/pubmed/22513949