Breast Cancer and Soy... What's the Latest Research?

Like all foods, soy contains many substances. The most researched substances in soy are its proteins and isoflavones. A natural compound from a plant that can act like estrogen in the body is called a phytoestrogen. Soy isoflavones are sometimes referred to as phytoestrogens and have the most potent estrogen-like activity of all common phytoestrogens. In spite of their name, phytoestrogens are not actually estrogens but are similar in structure.

What can soy do?

Due to the recent information about prescription hormone therapy, natural phytoestrogens are very popular and commonly used to combat menopause symptoms such as hot flashes and night sweats. In its natural form, the soy isoflavones are found attached to a protein. It should be noted that soy protein and soy isoflavones are not the same thing. Foods that contain soy protein can contain isoflavones but the content will vary widely. Depending on the processing involved, the content can vary anywhere from virtually zero to around 2 milligram of isoflavones per gram of protein. Therefore, for optimal benefit of the soy isoflavone, it is important to ascertain the isoflavone content of any particular soy product or food chosen.

New research on soy found no link to conditions that can increase cancer risk.

Because of Soy's suggested weak estrogen-like effects, concern has been voiced for the woman at risk for breast cancer. A number of studies have suggested that dietary factors, including isoflavones (estrogen-like plant compounds) might increase breast density. A new study included 358 postmenopausal women who averaged 55 years old. "Each day for two years, they took either a placebo or one of two dosages -- 80 milligrams or 120 milligrams -- of soy isoflavones, contained in soy-germ isoflavone tablets. The soy dosage levels are equivalent to the amount of isoflavones provided in two to four cups of soymilk." This recently published research on Soy found no link to conditions that can increase cancer risk. This is good news because it has been thought that increased breast density is associated with a higher risk of breast cancer. "These findings offer reassurance that isoflavones do not act like hormone replacement medication on breast density," the researchers concluded.¹

Tokyo hosted an international soy conference earlier this year. Some interesting studies and finding were presented, including:

1. Asian women who typically eat more soy than women in Western countries have lower rates of breast cancer than women in the United States.

2. Two symposiums concentrated on the use of soy protein in preventing the reoccurrence of breast cancer. Researchers found that soy intake was associated with pronounced survival rates and did not influence mammographic breast density.^1,2

A five-year data analysis of breast cancer survivors associated soy intake with a better outcome, and the National Cancer Institute states that for breast cancer survivors, soy foods, as part of a healthy diet and in moderate amounts, are safe to consume.²

What does all this mean?

A healthy lifestyle is key - including weight control...
Studies have linked adulthood weight gain with an increased risk of breast cancer. A significant number of research studies support claims that soy consumption can help you lose weight. Soy protein is a low-fat source of high-quality protein (compared to many other protein sources) that can help you build lean muscle mass. Plus, soy protein provides a good source of energy. When combined with exercise and a healthy diet, soy protein makes an excellent "partner" in a successful diet plan.

Act now and receive free soy samples from Revival Soy, more information can be found on the right.

1. 1. Maskarinec, G. et al. Various doses of soy isoflavones do not modify mammographic density in postmenopausal women, Journal of Nutrition 2009; 139: 981-986.

2. Messina MJ, Loprinzi CL., Soy for breast cancer survivors: a critical review of the literature, J Nutr. 2001 Nov;131(11 Suppl):3095S-108S.