Soy

The dairy industry has tried, for many years, to give a bad name to soy products. They claim that soy (milk) increases the risk of breast cancer in women and prostate cancer in men, because of the presence of isoflavones (a type of phytoestrogen) in it. The truth, however, is that isoflavones actually protect you from these and other ailments, whereas the abundance of estrogens in cow's milk is a factor in the direct correlation between the increase of dairy consumption and the increase of breast and prostate cancer.

Dr. Michelle McMacken explains the soy myth in more detail on Instagram:
https://www.instagram.com/p/Bzv22IGACgf/
https://www.instagram.com/veg_md/


More studies on soy consumption:
- Soy intake and cancer risk - review on NCBI website

- Soy consumption and the risk of prostate cancer - meta-analysis on NCBI website
- Soy Consumption and Gastrointestinal Cancer Risk - meta-analysis on Nature.com
- Soy Intake and Breast Cancer Risk - systematic review in JJCO journal

This study shows that it is a good idea to start soy consumption in childhood:
http://cebp.aacrjournals.org/content/18/4/1050

Skeptical of soy? Here’s what the science tells us:

BASICS: Soy contains isoflavones, a type of phytoestrogen that is 1000 times weaker than human estrogen & does not behave exactly like human estrogens in our bodies. Isoflavones block some of estrogen's effects & mimic others, generally resulting in health benefits; they also have antioxidant & anti-inflammatory properties. Soy has the highest protein & fat content of any legume & is high in iron & fiber.

WOMEN’S HEALTH: Soy has been shown to prevent breast cancer in the amounts consumed in Asia. A 2008 review showed that women averaging 1cup of soymilk/ 1/2cup of tofu per day had a 30% lower risk of developing breast cancer vs women who avoid soy. Soy has also been shown in many studies to reduce the risk of recurrence in breast cancer survivors. ​A recent study showed that breast cancer survivors who consumed the most soy had a 21% lower risk of dying of any cause over the 9-yr study, compared with low-soy consumers. Soy reduces the risk of endometrial cancer & can reduce menopausal hot flashes.

MEN'S HEALTH: A large 2010 systematic review showed that soy does not affect testosterone levels, sperm concentration, or sperm quality. Soy may lower the risk of prostate cancer by up to 50%. THYROID: Soy does not affect the thyroid in people with normal thyroid function and iodine levels. Whether or not you eat soy, you should meet your daily iodine needs (150mcg/day). If you take thyroid hormone, you may need the dose adjusted if you change your soy intake.

CARDIOVASCULAR RISK: Soy lowers blood pressure & LDL cholesterol.

REALITY CHECK: Some worry about estrogen & GMOs/pesticides from soy, but most dietary estrogen comes from dairy & meat products. Unlike soy phytoestrogens, animal estrogens DO mimic human estrogen in our bodies. Similarly, most GMO soy is used to feed chicken, pigs, & cattle, which are then consumed by people. Much of the soy grown for human consumption is non-GMO.

Remark: in South America GMO soy is indeed used for human consumption. Do try to avoid it, as it was genetically modified to survive larger quantities of the Roundup pesticide.