Zinc and Selenium are the Minerals that Fight Breast Cancer

Researchers at Pennsylvania State University have reported that glands in the breast have unique zinc requirements resulting from their need to transfer extraordinary amounts of zinc into milk during lactation. When nursing women's breasts are deficient in zinc, the result can be severe zinc deficiency in the infant, resulting in impaired growth and development. When zinc is deficient or not properly metabolized, breast cancer is often an additional outcome. Lack of zinc has been implicated not only in the initiation of breast cancer, but also in the transition, progression, and metastasis of the disease. When zinc is deficient, cellular functioning in the breast is compromised. (Genes and Nutrition, April 2)

In France, scientists report that estrogen receptor expression in breast cancers is associated with differentiated tumors and a more favorable prognosis. The greater the resemblance of cancerous breast cells to non-cancerous breast cells, the less threatening is the disease. Although the exact mechanism underlying the protection ERs play against cancer progression remains to be researched, these scientists studied the actions of ER alpha, and documented that one of the ways this ER inhibits invasion is though its first zinc finger. A zinc finger is a group of proteins organized around a zinc ion that can bind to DNA and influence gene regulation. (Advances in Experimental Medicine and Biology, 2008)

In other research, Dr. David Watts reviewed the hair trace mineral reports of thousands of women and found that a pattern of elevated boron, copper and calcium levels with lower levels of zinc occurred in women with breast cancer. According to Dr. Watts, boron and copper appear to make the body more sensitive to the stimulatory effects of estrogen, and less responsive to the quieting effects of progesterone. Zinc is the mineral that aids in the production and utilization of progesterone, so this pattern of mineralization makes women less progesterone responsive and more estrogen sensitive. Raising zinc levels and lowering boron, copper and calcium levels can bring these women into mineral balance and help in the creation of hormonal balance.

The primary gene protecting women from breast cancer, p53, is thought to be the most frequently mutated or altered gene in the development of cancer. This gene requires zinc, and if it is missing, the gene becomes mutated, resulting in it becoming inactivated or suppressed. Dysfunction of p53 is well documented in the development of breast cancer, indicating that a zinc deficiency is a risk factor for breast cancer independent of the levels of boron, copper and calcium.

Zinc is important in prostate gland function and may help prevent and treat prostate cancer. It has another important role in the lives of women too. Zinc is required for protein synthesis and collagen formation. Without adequate levels of zinc, skin begins to sag and lose its elasticity. The optimal balance ratio for copper and zinc is 1 to 10 according to nutrition experts Phyllis Balch CNC and James Balch M.D.

In addition to sagging skin, deficiency of zinc may result in the loss of the senses of taste and smell. It can cause fingernails to become thin, peel and develop white spots. Other possible signs of zinc deficiency for women include hair loss, high cholesterol levels, impaired night vision, increased susceptibility to infection, memory impairment, diabetes, skin lesions, and slow wound healing.

Food sources for zinc are brewer's yeast, egg yolks, kelp, lamb, legumes, lima beans, liver, meats, mushrooms, pecans, poultry, pumpkin seeds, sardines, seafood, soy lecithin, sunflower seeds, and wheat germ. Zinc is found in alfalfa, burdock, cayenne, chamomile, dandelion, eyebright, fennel seeds, milk thistle, nettle, parsley, rose hips, sage, skullcap, and wild yam. Zinc picolinate, zinc citrate, and zinc as methionine are good choices for supplemental zinc. These are available from many supplement companies.

The relationship between selenium status and intake among breast cancer patients was studied by scientists in Kuala Lumpur. 64 women with breast cancer and 127 matched controls were interviewed to obtain information on their habitual dietary intakes, demographic data, and medical history. Selenium status was determined from toenail and hair analysis. The researchers found that total energy and protein intake was significantly higher among controls than among the breast cancer cases. The selenium intake among the women with breast cancer was significantly lower than the controls. Breast cancer risk decreased with the increasing quartiles of selenium intake. Selenium in hair did not differ among breast cancer cases and controls, but selenium status in the nails of controls was significantly higher compared to the breast cancer cases. (Sinapore Medical Journal, March).

In a recent study done at the University of Washington, scientists investigated the signaling pathways modulated by selenium. They compared global gene expression profiles in mammary tissues from pubescent female rats maintained on a selenium (3ppm) diet with those on a standardized diet. The selenium-enriched diet altered the steady-state levels of genes involved in various cellular functioning, the most dramatic of which was the changes in the expression of multiple genes that regulate circadian rhythm.

The normal mammary tissue of rats fed the standardized diet showed little circadian oscillation relative to liver tissue. However, the mammary tissue of the selenium fed rats showed a progressive, time-dependent increase in the expression of circadian gene Per2, and a circadian regulated transcription factor. Further, the results showed that the expression of Per2 and transcription mitigated RNA was significantly decreased in mammary tumors arising in selenium fed rate, but not in tumors of rats on the control diet. This suggests that selenium-induced elevation in the expression of circadian genes was incompatible with mammary cancer. The researchers concluded that the Per 2 gene is an important target of selenium for cancer prevention. (Cancer Prevention Research, July, 2008)

Selenium's main role is inhibiting the oxidation of fats as a component of the enzyme glutathione peroxidase, one of the most powerful of the body's own antioxidants. When combined with vitamin E, selenium protects the immune system. It plays a vital role in regulating the effects of thyroid hormone on fat metabolism. In a study, men who consumed 200 mcg of selenium daily over a ten-year period had roughly half the risk of developing lung, prostate, and colorectal cancer compared with men who did not.

Symptoms of selenium deficiency are exhaustion, high cholesterol, infections, liver impairment, and pancreatic insufficiency. Westerners often do not have enough selenium, because it is processed out of the foods typically eaten. This is one of the reasons that American men are five times more likely than Japanese men to die from prostate cancer. The typical Asian diet contains four times the amount of selenium as the typical American diet.

Selenium is found in meat and grains, but the level depends on the soil content where the food was grown. It can be found in brewer's yeast, broccoli, brown rice, chicken, dairy products, garlic, kelp, liver, molasses, onions, salmon, seafood, vegetables, wheat germ, and whole grains. Perhaps the best source of selenium is Brazil nuts. Eating two of the nuts a day provides 240 mcg of selenium. Earl Mindell, in his Vitamin Bible, recommends 200 mcg of selenium intake daily.

Zinc
Selenium