Folate Deficiency and Cancer Risk

Epidemiologictd studies suggest that suboptimtd folate status is associated with an increeised risk of colorectal and other cemcers. It is difficult to determine the importtmce of folate per se, because the dietary sources of folate (mainly green leeify vegetables) tire tdso sources of a variety of other compounds 

---

Folate antagonists (eg, methotrexate and certain antiepileptics) are used ia treatment for various diseases, but their adininistration can lead to a functional folate deficiency. Folate utilization can be impaired by a depletion of ziac (see Zinc compounds). In humans, the intestinal bmsh border folate conjugase is a ziac metaHoenzyme (72). One study iadicates that the substantial consumption of alcohol, when combiaed with an iaadequate iatake of folate and methionine, may iacrease the risk of colon cancer (73). Based on this study, it is recommended to avoid excess alcohol consumption and iacrease folate iatake to lower the risk of colon cancer. 

The risk of colon cancer appears to be inversely related to calcium and folate intake. Calciums protective effect may be related to a reduction in mucosal cell proliferation rates or through its binding to bile salts in the intestine, whereas dietary folate helps in maintaining normal bowel mucosa. Additional micronutrient deficiencies have been demonstrated through several studies to increase colorectal cancer risk and include selenium, vitamin C, vitamin D, vitamin E, and 3-carotene however, the benefit of dietary supplementation does not appear to be substantial.11... 

Albumin (human) Epoetin alfa contains albumin, a derivative of human blood. Based on effective donor screening and product manufacturing processes, it carries an extremely remote risk for transmission of viral diseases. No cases of transmission of viral diseases or Creutzfeldt-Jakob disease have ever been identified for albumin. Anemia Not intended for CRF patients who require correction of severe anemia epoetin alfa may obviate the need for maintenance transfusions but is not a substitute for emergency transfusion. Not indicated for treatment of anemia in HIV-infected patients or cancer patients due to other factors such as iron or folate deficiencies, hemolysis, or Gl bleeding, which should be managed appropriately. Hypertension Up to 80% of patients with CRF have a history of hypertension. Do not treat patients with uncontrolled hypertension monitor blood pressure adequately before initiation of therapy. Hypertensive encephalopathy and seizures have occurred in patients with CRF treated with epoetin. 

Folate deficiency is associated with the increased risk of neural tube defects (spina bifida, anencephaly), cardiovascular diseases, megaloblastic anemia, and some cancers (Bailey et al., 2003 Finglas et al., 2006 Scott et al, 1999). Unfortunately, folate intake is suboptimal in most of the world s populations, even in developed countries (Scott et al., 2000). Therefore there is an urgent need to increase folate content and bioavailability in staple foods. Because of its large consumption worldwide, potato is an appealing target for enrichment. 

Folates Folates are foUc acid derivatives that are naturally present in foods. FoUc acid is the chemically synthesized form of folate. Folates are involved in many metaboUc pathways such as DNA and RNA biosynthesis, repair and methylation, and amino acid interconversions. These compounds possess antioxidant competence that protects the genome by preventing free radical attack [238]. In humans, folate deficiency is associated with a variety of disorders such as coronary heart disease, osteoporosis, Alzheimer s disease, and increased risk of breast and colorectal cancer [239]. 

Although folate is widely distributed in foods, dietary deficiency is not uncommon, and a number of commonly used drugs can cause folate depletion. Marginal folate status is a factor in the development of neural tube defects and supplements of 400 fj,g per day periconceptually reduce the incidence of neural tube defects significantly. High intakes of folate lower the plasma concentration of homocysteine in people genetically at risk of hyperhomo-cysteinemia and may reduce the risk of cardiovascular disease, although as yet there is no evidence from intervention studies. There is also evidence that low folate status is associated with increased risk of colorectal and other cancers and that folate may be protective. Mandatory enrichment of cereal products with folic acid has been introduced in the United States and other countries, and considered in others. 

In chapter 3, we briefly discussed the link between elevated homocysteine levels, increased acidity, and, ultimately, cardiovascular problems. While additional studies are required, promising scientific evidence suggests that folate (also known as vitamin Bg), vitamin B6, and vitamin BI2 are effective at lowering homocysteine levels and may ultimately play a role in reducing vascular disease. In addition, research has revealed an inverse relationship between folate and the occurrence of colorectal cancer.5 (In other words, the more deficient in folate you are, the greater your risk of colorectal cancer.)... 

Chronic overdrinking or binge-drinking alcoholism causes deficiencies of folate, thiamine, pyridoxine, vitamin A, and zinc, the combination of which causes multiple risks for disease, but mostly for cancer. 

---