"Inhibition of human breast cancer cell proliferation and delay of mammary tumorigenesis by flavonoids and citrus juices" by So, Guthrie, Chambers, Moussa, and Carroll (1996) reports that in women from developed countries, breast cancer is the most prevalent cancer; incidence is increasing worldwide at an average rate of approximately two percent annually. Chemotherapeutic techniques fail to reduce death rates from cancers of the breast, lung, brain, colon, prostate, ovary, and pancreas. Studies on diet and cancer offer information regarding naturally occurring anticancer agents. Research concludes that plant-based diets with whole grains, legumes, fruits, and vegetables reduce risk of cancer. Carotenes and antioxidant vitamins may act as anticancer agents, however studies are inconclusive.
Studies are also done with flavonoids, present in citrus and other fruits, vegetables, grains, seeds, nuts, tea, and wine; cytotoxic effects on HeLa cells and Raji lymphoma cells, antiproliferative effects on human lymphocytes and human breast cancer cells, and skin tumorigenesis suppression in mice has been demonstrated. The flavonoid, quercetin, shows growth-inhibitory effects "in human breast cancer cells, colon cancer cell lines, a lymphoblastoid cell line, acute lymphoid and myeloid leukemia cell lines, and squamous cell carcinoma cell lines" (3:168). Isoflavone, in soybeans, also demonstrates anticancer activity. So et al. investigated the inhibitory effects of naringenin and naringin (a flavonoid found in grapefruit and its glycoside) and concentrates of grapefruit juice and orange juice on mammary tumors in rats.
"Effects of linoleic acid and y-linolenic acid on the growth and metastasis of a human breast cancer cell line in nude mice and on its growth and invasive capacity in vitro" by Rose, Connolly, and Liu (1995) reports regarding the controversy concerning dietary fat intake and effects on breast cancer. Studies show ...