Iodine
Iodine is an essential trace element and a precursor of thyroid hormones. Thyroid hormones are required for normal development and metabolism. Moderate deficiency of iodine may result in goiter (an abnormally enlarged thyroid gland). Severe iodine deficiency results in a condition called myxedema in adults and cretinism in children. Iodine deficiency, in general, results in a wide spectrum of effects on growth and development, particularly on brain development. It is the most common cause of preventable mental deficit in the world. Iodine may be protective against radioactive iodine and consequent thyroid cancer. It is used therapeutically for the treatment of certain thyroid conditions. Rich sources are kelp (seaweed), mackerel, haddock, mussels, salmon, and prawns. Dosage is age-dependent, being 50 – 120 micrograms/day for those between 0-12 years, 150 micrograms/day for adults, and 200 micrograms/day during pregnancy and lactation.
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Iodine is a trace element that is essential for the synthesis of thyroid hormone. Both chronic iodine deficiency and iodine excess have been associated with hypertrophy and hyperplasia of follicular cells, attributed to excessive secretion of TSH. This may be associated to thyroid cancer risk, particularly in women…….There is no doubt that introduction of universal iodine prophylaxis in population previously in chronic iodine-deficiency leads to a changing pattern of more prevalent papillary thyroid cancer and declining of follicular thyroid cancer……… Iodine excess has also been indicated as a possible nutritional factor in the prevalence of differentiated thyroid cancer in Iceland, Hawaii and, more recently, in China. In conclusion: available evidence from animal experiments, epidemiological studies and iodine prophylaxis has demonstrated a shift towards a rise in papillary carcinoma, but no clear relationship between overall thyroid cancer incidence and iodine intake.o Knobel, M, & Medeiros-Neto, G. (2007). Relevance of iodine intake as a reputed predisposing factor for thyroid cancer. Arq Bras Endocrinol Metabol, 51(5), 701-12.
The protective effects of iodine on breast cancer have been postulated from epidemiologic evidence and described in animal models. The molecular mechanisms responsible have not been identified but laboratory evidence suggests that iodine may inhibit cancer promotion through modulation of the estrogen pathway…….. In addition to elucidating our understanding of the effects of iodine/iodide on breast cancer, this work suggests that iodine/iodide may be useful as an adjuvant therapy in the pharmacologic manipulation of the estrogen pathway in women with breast cancer.o
Stoddard, FR, Brooks, AD, Eskin, BA, & Johannes, GJ. (2008). Iodine alters gene expression in the mcf7 breast cancer cell line: evidence for an anti-estrogen effect of iodine. Int J Med Sci, 5(4), 189-96.A renewal of the search for a link between breast cancer and thyroid disease has once again demonstrated an increased prevalence of autoimmune thyroid disease in patients with breast cancer…….. Experimental findings showing the ability of iodine or iodine-rich seaweed to inhibit breast tumour development is supported by the relatively low rate of breast cancer in Japanese women who consume a diet containing iodine-rich seaweed.o
Smyth, PPA. (2003). The Thyroid, iodine and breast cancer. Breast Cancer Res, 5(5), 235-8.The relationship between breast cancer and thyroid diseases is controversial. Discrepant results have been reported in the literature. The incidences of autoimmune and nonautoimmune thyroid diseases were investigated in patients with breast cancer and age-matched control individuals without breast or thyroid disease…….Our results indicate an increased prevalence of autoimmune and nonautoimmune thyroid diseases in breast cancer patients.o
Turken, O et al. (2003). Breast cancer in association with thyroid disorders. Breast Cancer Res, 5(5), 110-3.The role played in thyroid hormonogenesis by iodide oxidation to iodine (organification) is well established. Iodine deficiency may produce conditions of oxidative stress with high TSH producing a level of H_2O_2, which because of lack of iodide is not being used to form thyroid hormones…….. the Japanese experience may indicate a protective effect against breast cancer for an iodine rich seaweed containing diet.o
Smyth, PP. (2003). Role of iodine in antioxidant defence in thyroid and breast disease. Biofactors, 19(3-4), 121-30. The authors have analyzed 48 cases of breast cancer detected among more than 16,000 patients with thyroid pathology including thyroid carcinoma…….. It is supposed that hypersecretion of prolactin and gonadotropins might play some role in such association. Radiotherapy and chemotherapy for breast carcinoma also can be predisposing factors to the development of subsequent thyroid pathology.o
Romanchishen, AF, & Kolosiuk, VA. (2003). Breast cancer in thyroid diseases. Vestn Khir Im I I Grek, 162(11), 21-5.An unexpected association with breast cancer and thyroid disorders was found during a review of 91 cases of benign and malignant ovarian adenofibromas……..This unexpected association found between glandular/cystic adenofibromas, breast cancer, and thyroid disorders might be explained by defects common to these organs……. Disorders of some of these organs have been linked by common genetic changes and it is known that these organs are under the influence of similar hormones. Mutations of PTEN (phosphatase and tensin homolog) have been found in breast and thyroid cancer.o
Silva, EG et al. (2002). The Association of benign and malignant ovarian adenofibromas with breast cancer and thyroid disorders. Int J Surg Pathol, 10(1), 33-9.INTESTINAL CANCER:
We evaluated partially hydrolyzed whey protein (WPH) for inhibitory effects on the development of colon aberrant crypt foci (ACF) and intestinal tumors in azoxymethane (AOM)-treated rats…….. At this time point, differences in colon tumor incidence with diet were not observed; however, WPH-fed rats had fewer tumors in the small intestine.
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Xiao, R et al (2006).Dietary whey protein lowers serum C-peptide concentration and duodenal SREBP-1c mRNA abundance, and reduces occurrence of duodenal tumors and colon aberrant crypt foci in azoxymethane-treated male rats. J Nutr Biochem, 17(9), 626-34.The impact of different dietary protein sources (whey, casein, soybean, red meat) on the incidence, burden and mass index of intestinal tumors induced by dimethylhydrazine in male Sprague-Dawley rats was assessed……. Whatever the mechanism(s), dairy proteins, and whey proteins in particular, offer considerable protection to the host against dimethylhydrazine-induced tumors relative to the other protein sources examined.o
McIntosh, GH, Regester, GO, Le Leu, RK, Royle, PJ, & Smithers, GW (1995). Dairy proteins protect against dimethylhydrazine-induced intestinal cancers in rats. J Nutr, 125(4), 809-16.This study investigates the influence of two formula diets containing 20 g/100 g diet of either whey protein concentrate or casein or Purina mouse chow, on the humoral immune responsiveness and dimethylhydrazine induced colon carcinogenesis in A/J mice…….In conclusion, a whey protein diet appears to significantly inhibit the incidence and growth of chemically induced colon tumors in mice.o
Bounous, G, Papenburg, R, Kongshavn, PA, Gold, P, & Fleiszer, D (1988). Dietary whey protein inhibits the development of dimethylhydrazine induced malignancy. Clin Invest Med, 11(3), 213-7.Breast Cancer:
Milk contains rumenic acid, vaccenic acid, branched chain fatty acids, butyric acid, cysteine-rich whey proteins, calcium and vitamin D; components, which have the potential to help prevent breast cancer.o
Parodi, PW (2005).Dairy Product Consumption and the Risk of Breast Cancer. Journal of the American College of Nutrition, 24. Results from animal studies suggest that whey protein, but not casein protein, may provide protective effects against experimentally induced breast cancer in animals……. These results suggest that consumption of whey protein-containing diets may reduce the risk of developing colon tumors.o
Hakkak, R, Korourian, S, Ronis, MJ, Johnston, JM, & Badger, TM (2001). Dietary whey protein protects against azoxymethane-induced colon tumors in male rats. Cancer Epidemiol Biomarkers Prev, 10 (5), 555-8. The glutathione (GSH) antioxidant system is foremost among the cellular protective mechanisms. Depletion of this small molecule is a common consequence of increased formation of reactive oxygen species during increased cellular activities……… Case reports are presented which strongly suggest an anti-tumor effect of a whey protein dietary supplement in some urogenital cancers.o
Bounous, G (2000).Whey protein concentrate (WPC) and glutathione modulation in cancer treatment. Anticancer Res, 20(6), 4785-92.