Soya- could i be eating too much

[gnosis]

I am considering becoming a vegan and have switched to soya milk. i have read a lot about soya and it seems that some think it is really good for you and others say it may even cause cancer. i have also read about phytoestrogens in soya and so i am slightly worried. i am consuming about a glass of soya milk a day and probably about 75g of tofu some days. my question is am i having too much soya and also are any of these claims about soya having carcinogenic affects or the phytoestrogens having averse affects on humans substansiated by human studies? also is there an optimum amount of soya you would recomend, given it's good and bad press? thanks

[yoshi]

i am asian and i grew up in an asian society where we eat a lot of soy bean products-soy sauce,tofu-fried,braised,cooked,raw,sheets,rolls,milk etc.
since it is so common in our society,we have no problem getting tofu and soy milk fresh everyday.
but in this country where most of us buy them in supermarket and healthfood stores,some of them can be stale and start fermenting,this is where yeast and fungal infection can come in.
make sure it is fresh and odorless when you prepare them,fresh tofu should have no odor.if it smells ,then it has gone bad.
if you buy a piece of tofu ,make sure it is soaked in fresh clean water,and change the water frequently.
if it smells somewhat when you bring it home,keep it submerge in fresh water and change the water daily until the odor go away.
Happy eating!!
the tofu in asian supermarket turns over quickly,if you live nearby a chinatown,buy there,it is cheaper and fresher.

[SmilerSS]

My sister has been been vegan for years,,,you definitely have to educate yourself like anything else,,she did alot of reading to insure she got the adequate/substitute values in her meals. She is a pro in it..I can ask her anything about what non-vegan will equal a vegan value. Definitely, have to learn to cook, which is not my dept...but, I mostly a veggie person anyway.  PETA.org website has all kinds of stuff for vegans, receipe books, introductry(sp) type stuff..my sister first went vegeratarian then vegan..made the transition for her to vegan easier.

I drink soy milk everyday and love it..my relaxing drink..so good.
Hang in there,,it is a change--major healthy life-style change..

Medically speaking ,I am in a transition to Chinese Medicine..unless my condition is impossible to treat otherwise, then will seek medical, but last resort..so alternatives are good----we are taught alot of old school thought,,,not that it it is bad, but may not work for you, me or others.....like Chinese Medicine is dated back 2,500 years & works and may even go back further.....hey,,,been there & done it and need a new way of life.......freedom of choice & this is not to undermine the medical field at all..it saves lives & heals..but, in my condition, no longer works.,,,,

I love alternatives!!!!!!!!!

Good luck,
Suzette

[Anai Rhoads]

gnostic,

You're doing great! Remember that too much protein can affect your kidneys, so be sure to keep yout intake below 60 grams daily if you can.

I have been a vegan for a few years and simply love it. If you need any help on becoming a vegan, you can find me on the orgasmicvegan.org. I offer a free question and answer section for that site.

And as for your question, its a lot safer to eat soy products than it is to eat meat that is packed with hormones, anti-biotics and other chemicals.

Good luck on going vegan!

Anai Rhoads

[Kevin Pho, MD]

Hello - thanks for asking your question.

There are no consensus data regarding the impact of soy and cancer.  There are several small studies suggesting that the ingestion of soy reduces the risk of breast cancer (with the phytoestrogens in soy having an antiestrogenic effect).  

Here are the conclusions from some of these studies:
"These results show that high soy intake in childhood in Asian-Americans is associated with reduced breast cancer risk. Risk may be further reduced by intake as an adult."
Wu, AH, Wan, P, Hankin, J, et al. Adolescent and adult soy intake and risk of breast cancer in Asian-Americans. Carcinogenesis 2002; 23:1491.

"The results suggest that regular soyfood consumption may reduce the risk of breast cancer, particularly for those positive for ER and PR; the effect may be modified by body mass index."
Dai, Q, et al. Population-based. Br J Cancer 2001; 85:372.

"Phytoestrogens appear to have little effect on breast cancer risk at the levels commonly consumed by non-Asian US women: an average intake equivalent to less than one serving of tofu per week."
Horn-Ross, PL, John, EM, Lee, M, et al. Phytoestrogen consumption and breast cancer risk in a multiethnic population: the Bay Area Breast Cancer Study. Am J Epidemiol 2001; 154:434.

There is no magic number of optimum intake of soy.  In moderation, there should be minimal adverse effects.  It should be part of a combination of a balanced vegan diet.  Studies show that at least 25 gms of soy should be eaten to have a cholesterol-lowering effect.

Followup with your personal physician is essential.

This answer is not intended as and does not substitute for medical advice - the information presented is for patient education only. Please see your personal physician for further evaluation of your individual case.

Thanks,
Kevin, M.D.