Sliced_tempeh_NM site

Return to blog

The word on soy

The word on soy By Belinda Llewellyn ND, Naturopath, Gaia Natural Medicine The sources of soy, effects of soy on the body and what to look out for when it comes to choosing pure s...

The word on soy

The word on soy
By Belinda Llewellyn ND, Naturopath, Gaia Natural Medicine

The sources of soy, effects of soy on the body and what to look out for when it comes to choosing pure sources of soy.


I know people who can’t get enough soy, but I also know others who avoid it completely as they’re afraid of potential health risks. There’s so much conflicting information out there it’s hard to know what to believe. But take a deep breath and relax because soy, like all foods, has pros and cons associated with it.


Soy is everywhere. Even if you’re not consciously choosing to eat soy, if you eat processed foods you will be consuming some form of soy. Be wary of the following hidden soy ingredients:

  • soy lecithin
  • soy protein concentrate or isolate
  • soy isoflavone concentrates
  • textured or hydrolysed vegetable protein
  • soy oil (common vegetable oil).


Stick to traditional forms of ORGANIC soy, which use the whole soybean (soya bean). These sources can be fermented or non-fermented. Fermented soy is seen as the healthiest option as it enhances digestion and promotes healthy gut bacteria.


  • Miso – fermented soybean and grain (rice or barley) paste makes a yummy soup broth.
  • Tempeh – fermented soybeans packed tightly together to form a block and sold marinated or plain.
  • Tamari – fermented soy sauce is a great alternative to conventional soy sauce.
  • Soybean sprouts – easy to do yourself and are a highly nutritious addition to salads or stir-fries.


  • Soy milk – when purchasing, aim for minimal ingredients (no sweeteners, flavouring or additives of any description) and make sure it is made from ‘whole soybeans’. You could even make your own.
  • Tofu – soybean curd available in silken or firm types are great alternatives to fish, meat and eggs.


To avoid nasties (toxic metals and chemicals) and the potential harmful effects of soy, stay clear of any genetically modified (GM) soy, which is likely to be used in most non-organic products. Aim to buy organic soy products because they are ultimately the only reliable and health-promoting source.


Soy is one of the best food sources of phytoestrogens. Phytoestrogens can balance oestrogen levels in the body. So if you suffer from a condition where oestrogen is dominant (heavy menstrual bleeding), phytoestrogens can block oestrogen and reduce symptoms. Whereas if you struggle with low levels of oestrogen, like in menopause, phytoestrogens are able to enhance oestrogen levels and reduce harmful risk factors and debilitating symptoms.


When soy is consumed in moderation (one to two serves per day) as part of a balanced wholefood diet, it has these potential health benefits:

  • reduces the risk of hormone-related cancers – prostate and breast
  • hormone balancing – alleviates heavy menstrual bleeding and menopausal symptoms
  • decreased risk of cardiovascular disease
  • osteoporosis prevention and treatment.

Most of the negative press around soy is related to GM and highly processed soy products along with excessive daily intake.


Here are some considerations when consuming soy:

  • If you’re allergic or sensitive to dairy products you could also be to soy. Soy and dairy are both known in Chinese and Ayurvedic medicine as ‘damp’ foods, which can enhance the production of phlegm.
  • Substances called goitrogens are found in soy. They suppress thyroid function by interfering with the body’s ability to use iodine. Also found in broccoli, cauliflower, cabbage and kale, they can be destroyed by light cooking.
  • As soy can interfere with thyroid function, the metabolism can become sluggish, which can add to fluid retention and weight gain.
  • Soy, along with other legumes and grains, contains phytic acid, which binds to minerals (calcium, magnesium, zinc, iron) potentially causing nutrient deficiencies. Soaking and sprouting removes the phytic acid.
  • Soy formulas are not recommended for infants as they may promote soy allergies.


    • Eat ORGANIC soy products only and avoid all GM.
    • Eat soy in moderation as part of a balanced wholefood diet.
    • Enjoy one to two serves of traditional (fermented) soy a day.
    • Check food labels for unwanted and often nasty soy by-products.


If you still have concerns about soy, consult your naturopath or clinical nutritionist for guidance. We can do allergy testing to ascertain if your body is coping with soy and point you in the right direction for the best foods (soy or not) for your particular constitution and health status.

Ultimately, the better you know yourself, the better equipped you will be to know what foods do and don’t work for you, including soy.


Belinda Llewellyn and her Naturopathic Clinic in Bayswater, Gaia Natural Medicine, are a part of the Nourish Melbourne Community, offering Nourish Melbourne Members 20% off their initial consult and 10% off all further visits. Click here to find out more about our partnership with Gaia Natural Medicine and here for more info about becoming a Nourish Melbourne Member.