Women diagnosed with breast cancer should not eat soya products as the active ingredient Limits the effectiveness of the treatment to tackle the disease

It is considered a healthy alternative than milk-and well-known popular with crowd yummy mummies.

But experts warned that women should start consuming soy milk after a breast cancer diagnosis-because it can limit the effectiveness of treatment.

Tamoxifen could be hampered because of the active compounds in soy, genistein, interference with the action of the drug, a study found.

Paradoxically, claiming the natural ingredients are safe for women if that's part of their diet prior to diagnosis, researchers.

Professor Leena Hilakivi-Clarke, Georgetown Lombardi Comprehensive Cancer Center, which conducted biological pathway in mice, explains that the genistein intake is very important.

"Estrogen Drive most breast cancer growth, but high soy intake among women in Asian countries has been associated with breast cancer rates are five times lower than Western women, who eat far less soy," he said.

We have solved the puzzle in our rat model. See, while many Oncologists recommend their patients to take supplements or eat foods soy isoflavones, our results suggest a more nuanced message.

Our results indicate that patients with breast cancer will continue to consume soy foods after diagnosis, but not to start them, if they are not consumed genistein before.

The study, published in the journal clinical cancer research, can help patients improve the role that diet plays in their treatment.

Principal researcher Dr. Zhang Xiyuan added this long standing renewable use of genistein before diagnosis has similar actions to Tamoxifen.

Inhibiting mechanism known as autophagy, which will allow the cancer cells survive, which helps explain why tamoxifen works, he said.

However, it began to consume it after developing breast cancer did not trigger the immune response of anti tumor in order to remove cancer cells when tested in mice.

Genistein eat as adults have a 7 percent chance of recurrence of breast cancer after tamoxifen treatment, compared with 33 per cent repeats on mice exposed to genistein only after developing breast cancer.

Dr. Zhang added: we do not yet know why this makes the animals resistant to the beneficial effects of tamoxifen and an increased risk of cancer relapse.