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Breast Cancer Prevention

The hormone estrogen has long been known to be a major cause of breast cancer. The hormone testosterone also contributes to the development of breast cancer in women because it is converted into estrogen by breast cells. In 1990, Joachim Georg Liehr, Ph.D., and Deodutta Roy, Ph.D., published a study in the Journal of Free Radical Biology and Medicine to show that estrogen stimulates breast cells to produce the toxic cancer-causing free radicals.1 Two endogenous (made by the body) hormones that also stimulate breast cells to produce these cancer-causing radicals are a group of hormones called prostaglandins and prolactin.


Fatty acid types of this hormone cause breast cells to produce a cancer-causing free radical called singlet oxygen. The phytochemical carotene and the peptide glutathione, both members of the cancer detoxification system, protect breast cells against these potent carcinogens. Vegetable oils, with the exception of olive oil, contain ingredients that stimulate prostaglandin production. Therefore, olive oil should be the only oil allowed in the diet of women who want to practice breast cancer prevention. Many cookies, pastries, cakes, breads, crackers, and other foods including some peanut butters contain partially hydrogenated vegetable oils, which by their nature contain cancer-causing trans-fatty acids. Studies show that women who have the highest amount of trans-fatty acids in their bodies have the highest rates of breast cancer.2 They should therefore avoid all foods containing partially hydrogenated vegetable oils. Reading food labels is a life-saving activity.

Insulin-Like Growth Factor, Prolactin, Growth Hormone, and Prostaglandin E2

The most current research studies are proving a very strong relationship between a woman's risk of developing breast cancer and blood levels of the hormones insulin-like growth factor (ILGF), prolactin (PRL), growth hormone (GH), and prostaglandin E2 (PGE2).

As part of a sound breast cancer preventive protocol or regimen the A.P. John Cancer Research Institute recommends every woman on reaching the age of 35 undertake a hormonal profile test. This test determines her blood levels of the following hormones: estrogen, testosterone, ILGF, PRL, GH, and PGE2. We recommend follow-up tests every 3 to 5 years, depending on the results of each test.

Reducing elevated levels of any of these hormones would certainly enhance every woman's chances of avoiding breast cancer in her lifetime.

The key to the prevention of breast cancer lies in maintaining a healthy cancer detoxification system. Following our dietary guidelines and taking our suggested supplements for maintaining such a system will provide every woman with her best chance of avoiding breast cancer. Keep in mind, however, that lifestyle abuses, as outlined herein, can impair the functions of this system.


Obesity increases the production of the steroidal hormones estrogen and testosterone in women's bodies. The role of endogenous (produced by the body) steroid hormones in pre- and post-menopausal breast cancer has been investigated in the European Prospective Investigation into Cancer and Nutrition (EPIC) in the largest studies conducted to date on this topic. EPIC has shown that both estrogens and androgens increase breast cancer risk whereas sex hormone binding globulin (SHBG) decreases risk after menopause. In parallel, overweight and low physical activity increase breast cancer risk after menopause. On the contrary, before menopause, androgens increase breast cancer risk, progesterones decrease risk, and SHBG and obesity are not associated with risk. These findings provide strong clues for further investigations of the metabolic and hormonal factors specifically related to pre- and post-menopausal breast cancer. EPIC found that the consumption of fruit and vegetables is not associated with breast cancer risk. This is an important finding as it helps to narrow down the factors potentially involved in breast cancer etiology (origins) and prevention.3 These facts explain why obese women are more likely to develop breast cancer, particularly after menopause, than women of normal weight. The increased incidence of breast cancer also depends to some extent on ethnic origins.4

Over-the-Counter, Prescription, and Illegal Drugs

When drugs are abused, they deplete the body's stores of a chemical called glucuronic acid. The cancer detoxification system uses glucuronic acid to regulate blood levels of estrogen and also to flush cancer-causing chemicals from the body. This process is called conjugation or glucuronicdation. A phytochemical found in fruits and vegetables called d-glucarate enhances the process of glucuronidation and therefore helps prevent breast cancer. We recommend every woman over the age of 35 take 1,000 mg daily of calcium d-glucarate as part of a sound breast cancer prevention program.


Alcohol abuse can impair liver functions and reduce the number of cells producing glucuronic acid. This is one reason that alcohol abuse can increase a woman's risk of developing breast cancer.5

Dietary Deficiencies

A diet lacking the necessary cancer-fighting chemicals and containing cancer-causing ones weakens the cancer detoxification system and can therefore increase a woman's chance of developing breast cancer.6



  1. J.G. Liehr and D. Roy, "Free Radical Generation by Redox Cycling of Estrogens," Free Radical Biology and Medicine 8 (1990): 415–23.
  2. V. Chajès, A.C.M. Thiébaut, M. Rotival, E. Gauthier, V. Maillard, M-C. Boutron-Ruault, V. Joulin, G.M. Lenoir, and F. Clavel-Chapelon, "Association between Serum Trans-Monounsaturated Fatty Acids and Breast Cancer Risk in the E3N-EPIC Study," American Journal of Epidemiology 167 (2008): 1312–20.
  3. World Health Organization, International Agency for Research on Cancer, EPIC Project, Elio Riboli, Coordinator, "Key Findings" (accessed October 6, 2011).
  4. A.G. Renehan, M. Tyson, M. Egger, R.F. Heller, and M. Zwahlen, "Body-Mass Index and Incidence of Cancer: a Systematic Review and Meta-Analysis of Prospective Observational Studies," The Lancet 371 (2008): 569–78. The following study finds differences in the link between obesity and breast cancer as well as other cancers in the Asia-Pacific populations: C.L. Parr, G.D. Batty, T.H. Lam, F. Barzi, X. Fang, S.C. Ho, S.H. Jee, A. Ansary-Moghaddam, K. Jamrozik, H. Ueshima, M. Woodward, R.R. Huxley, and the Asia-Pacific Cohert Studies Collaboration, Body-Mass Index and Cancer Mortality in the Asia-Pacific Cohort Studies Collaboration: Pooled Analyses of 424,519 Participants," The Lancet Oncology 11 (2010): 741–52.
  5. The following article supports this in an oblique manner in that it states that toxins, including excess estrogen, are bound or attached in the liver to a chemical called glucuronic acid. The bound toxin or estrogen is then excreted in bile and eventually eliminated as a waste product in the stool: A.S. Heerdt, C.W. Young, and P.I. Borgen, "Calcium Glucarate as a Chemopreventive Agent in Breast Cancer," Israel Journal of  Medical Sciences 31 (1995): 101–05.
  6. Marcus Laux, "Breast Cancer Alternative Treatments and Prevention," HeartSpring Web site (accessed October 5, 2011).
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When I called A.P. John Cancer Institute, I was scared and desperate to find answers.  Having been diagnosed with Stage 2 Cervical Cancer, I was ready to do everything...

- Debbie - Cervical Cancer

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