Monday, 1 October 2012

SOY: the advantages, disadvantages and what you should be cautious about

The soy debate has been going on many years and research is often conflicting or inconclusive. Sure it may seem like an ideal alternative to dairy, however the active components in soy have a strong biochemical affinity for cellular receptors in our body and can heavily influence hormonal processes. These days, there are a wide range of alternative milks to choose from such as coconut, almond, hazelnut, rice and quinoa so there is no need to feel deprived if you choose to avoid both dairy and soy.
There are two types of soy products – unfermented such as most soy milks, soy beans and tofu. Fermented include soy sauce (traditionally made), tempeh, Natto and miso.
So with all the ongoing conflicting evidence, should you choose to include a small amount for the medicinal value? Here is a brief discussion on the pros and cons of soy products to help you decide:

*A convenient alternative way to replace dairy incase of allergy or ethical choices.
*A huge amount of soy foods come from genetically modified soybeans which are linked to allergies, infertility and disease.
*Fermented soy is a great source of Vitamin K2, for optimal bone and cardiovascular health.
*Soy crops are heavily sprayed with toxic and carcinogenic pesticides and herbicides
*Traditional evidence linked to lower incidences of cancer (when soy is used as a CONDIMENT – small portions of fermented soy in moderation)
*Soy beans (the unfermented variety) naturally contain ‘anti-nutrients’ which contribute to various health issues, further discussed below.
*Offers a vegetarian source of amino acids, especially beneficial to a vegetarian or vegan diet.
*Phytates- bind to and prevent absorption of key minerals in the body.
*Goitrogens – interfere with thyroid hormone synthesis and  induces decreased function.
*Trypsin inhibitors – interfere with protein digestion and pancreatic function.
*Phytoestrogens and isoflavones – bioavailable estrogenic compounds that interact with estrogen receptors and block normal estrogen, increases risk for breast cancer.
*Whole cooked soybeans are high in fibre and help promote beneficial intestinal bacteria.
*Soy products are sometimes fortified with vitamins and minerals in a harmful form (vitamin D2 is often unstable and potentially toxic)
*Fresh young soybeans – Edamame, are a great source of vegetarian protein, carbohydrates and fibre.
*The B12 fortified in soy products has poor bioavailability and therefore wouldn’t contribute beneficially to vegan/vegetarian B12 needs.
*Past evidence have found a slight beneficial effect of soy isoflavones on cholesterol profiles, cardiovascular health and reduction of hot flushes however in a recent review, it has been touted as inconclusive evidence.
*Soy products that are chemically altered at high temperature processing such as Textured Vegetable Protein (TVP) and Soy Protein Isolates forms a carcinogenic molecule that should be avoided.

*Soy products may contain heavy metals such as aluminum which is neurotoxic.

*The hormonal compounds in soy can have a major influence on altering women’s menstrual cycles and reproductive function if over consumed.

*The estrogenic compounds in soy may potentially influence male (particularly adolescent) testosterone levels and developmental growth. (studies are relatively inconclusive)

In conclusion, a small amount may not be harmful but choose your soy products wisely – always go organic, non-genetically modified and ideally traditionally fermented but minimally processed in order to reap the rewards.
J Laura