Estrogen - good, bad, maybe, maybe not. Soy, yes, no, maybe, maybe not. Once you have had breast cancer, you need to be careful about estrogen and soy (which has some estrogen) and every time you turn around, they try to confuse you some more.
Here is the latest article which says estrogen may protect some people from breast cancer. Routinely women used to be given hormone replacement therapy, which included estrogen and progesterone, to relieve menopause symptoms. Then it was determined that HRT actually raised the risk of breast cancer. Once it stopped being prescribed, breast cancer rates started dropping.
A breast cancer diagnosis also provides information for the patient and doctor if your cancer is Estrogen receptor (ER), progesterone receptor (PR), and Her2 positive or negative. If you are ER and PR positive, you should benefit from chemo. If you are Her2 positive, you can also be treated with Herceptin.
However if you are ER positive, you need to avoid soy (until another study comes out to tell us differently) and estrogen as the current belief is that an ER positive cancer will feed off the estrogen in soy or in medical treatments.
If this isn't confusing enough, then they change their minds and a new study comes along and say the opposite. So clearly its a conspiracy to keep us all confused.
I have ER positive, PR positive, and Her2 negative breast cancer. I hate tofu and because of this confusion I can use it as an excuse not to eat it. I do eat somethings that have tofu in them - like Hot & Sour soup which I eat a few times a year. But now I can skip tofu as a rule.
So you may call me confused but I don't have to eat tofu.