Body mass index (BMI) should be taken into account when assessing a cancer patient's vitamin D status, according to researchers at Cancer Treatment Centers of America (CTCA), who found that obese cancer patients had significantly lower levels of vitamin D compared to non-obese patients.
The association between vitamin D and obesity remains unsettled with studies reporting conflicting findings on the relationship between the two. This association assumes even greater importance in cancer because of the alleged role of vitamin D in cancer.
"Currently, the dietary recommendations for vitamin D do not take into account a patient's BMI," said Carolyn Lammersfeld, national director of nutrition for CTCA and a principal investigator in the study. "We investigated the relationship between vitamin D and BMI in a large sample of cancer patients and found that as BMI groups increased from normal to overweight or obese classifications, there was a significant decrease in vitamin D."
The researchers evaluated a group of 740 cancer patients seen at CTCA from January 2008 to June 2008. Of the 740 patients, 303 were male and 437 female, with a mean age at presentation of 55.7 years (SD = 10.2). The mean BMI was 27.9 kg/m2 (SD = 6.7). The most common cancers were lung (134, 18.1%), breast (131, 17.7%), colorectal (97, 13.1%), pancreatic (86, 11.6%), prostate (45, 6.1%) and ovarian (39, 5.3%). The mean vitamin D (serum 25(OH)D) was 21.9 ng/ml (SD = 13.5).
The study concluded that obese cancer patients (BMI >=30 kg/m2) had significantly lower levels of vitamin D compared to non-obese patients (BMI <30 kg/m2). BMI should be taken into account when assessing a patient's vitamin D status and more aggressive vitamin D supplementation should be considered in obese cancer patients, researchers determined.
This study was presented at the American Society of Clinical Oncology (ASCO) annual meeting, May 29-June 2, 2009, and was publicly released on ASCO's Web site, www.asco.org, on May 14, 2009.
About Cancer Treatment Centers of America
Founded in 1988, Cancer Treatment Centers of America (CTCA) is a national network of hospitals providing a comprehensive, fully integrative approach to cancer treatment. CTCA serves patients with advanced cancer from all 50 states at facilities located in suburban Chicago, Philadelphia, Tulsa and suburban Phoenix. For more information about Cancer Treatment Centers of America, go to cancercenter.com.