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Why soy confused?Making sense of a diet dilemmaA healthy alternative to dairy, or not worth the risk? Siobhan Moylan reports.

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“My barista said he never drank soy milkas he didn’t want ‘man boobs’. ”

‘Soy milk’s bad for you’’ quipped afriend as I ordered a soy latte. ‘‘Idon’t know if it is or it isn’t,’’ Iresponded, but admitted to being

aware of the recent resurgence of an anti-soyzeitgeist permeating the culinary and coffee-loving world.

My local barista told me he never dranksoy milk as he didn’t want to grow ‘‘manboobs’’, yet a menopausal friend said hersymptoms diminished when she made theswitch to soy products. Soy confused?

It is true the wheels fall off the soybandwagon every few years. In New Zealandin 2012 there were calls for soy-based babyformula to be taken off supermarket shelvesafter research emerged suggesting exposureto soy in the womb or in childhood couldaffect female fertility. And then there’s theBonsoy story, where more than600 Australians have joined aclass action against Bonsoy Soymilk, claiming they got sick froman overload of iodine. With all thegood and bad press surroundingthe legume it’s hard to makesense of what types of soy oneshould be consuming.

Professor Mark Wahlqvist is along-standing member of theWorld Health Organisation’sNutrition Advisory Panel. He isalso editor of the Asia PacificJournal of Clinical Nutrition. Hiswork on the legume is extensive.He says it’s vital to distinguishbetween traditional and modernforms of soy.

Traditional forms of soy foodsinclude tofu, bean curd and

tempeh (principally used in Indonesia). InJapan, traditional forms include miso soup,edamame and a fermented form of soy callednatto. ‘‘Traditional forms of soy are all fairlyintact, they haven’t been broken down intocomponents; the whole bean is eaten, or hasbeen processed by the traditional foodtechnology, like fermentation,’’Wahlqvist says.

The forms of soy consumed in the Westare often based on soy isolates, where theprotein is used as a food ingredient, so thetype of soy we ingest here is not the typegetting all of the positive spin, nor is the waywe consume it. In Asia, soy products in theiroriginal form are used as condiments andnot to excess. ‘‘In the West, soy is used inreconstituted products like soy milk, meatlook-alike products, protein bars and after-

gym-workout shakes,’’ Wahlqvist says.He says consumers should be mindful that

when they consume products that do notcontain soy in its pure form, they may missout on the health benefits that exist in thetype consumed in Asian countries.

That said, he also cautions against soy‘‘scare’’ stories that do not give the wholepicture; for example, that soy causes thyroidsuppression. It’s true soy does containgoitrogens – substances that depress thyroidfunction, but he says: ‘‘Even though the

goitrogenic activity of soy is low, it’s true thatit could be exacerbated by iodine deficiencywith resultant goitre and thyroid disease.But this applies to several other foods likebrassica [cruciferous vegetables] none ofwhich we would want to discourage. The realissue is dealing with iodine deficiency.’’

Earlier in 2013, Food Standards AustraliaNew Zealand brought in a law allowingmanufacturers to make health claims abouta range of foods including soy products.Prior to this, nutritional claims could bemade but not health claims such as ‘‘thisfood is good for strong bones’’.

Wahlqvist says: ‘‘I resisted any movetowards a health claim for soy protein [in theUS and Australia], and still do now thathealth claims are possible in Australia, as itwould have, has and will encourage so-called ‘value-addedness’ of food by splittingit apart.’’ He says more studies are neededbefore any value-added benefits can be madeon non-traditional soy products.

John Eden, Associate Professor of

reproductive endocrinology at theUniversity of NSW, says we have nothing

to fear when it comes to the endocrinesystem and soy products in the amounts

typically consumed in the West.That said, he asserts glowing reviews

can be just as confusing to the soy story.He and his team published a study in 2001concluding soy products, including milk,powders, cheese, the works, do not help withthe incidence of hot flushes in menopausalwomen.

A similar peer-reviewed study conductedin 2009 in Germany concluded the samething.

What about women trying to get pregnant,should they avoid soy products? Eden saysthis is another myth and that estrogenicactivity is everywhere.

‘‘It’s in the water, other foods, cosmetics,everywhere – the quantities in soy are little.To assert that soy products can changeendocrine system function is nonsense, itreally does come down to having a balanceddiet,’’ he says.

Can soy alter a woman’s menstrual cycle?‘‘Yes,’’ Eden says, ‘‘but not significantly.

As long as a woman is having at leastsix periods a year, that is considered ‘normal’.Exactly how soy achieves a delay effect isopen to speculation but more importantlyit is not harmful. Just before I picked up thephone to you I downed some cheese, and asoy drink.’’