Many women with PCOS also suffer from low thyroid function, compounding their problems with excess weight. Several ladies have emailed me regarding the use of soy lecithin to obtain DCI from dietary sources with concerns over whether it will exacerbate hypothyroid conditions.
Soy products are widely consumed in our society in modern times, especially as food additives to increase protein content or to emulsify other ingredients.
A large body of research into the effects of soy protein has found that it interferes with thyroid hormone production and function and can even cause goitres in healthy children and adults when consumed on a regular basis.
Soy lecithin is an oil component of soybeans – it has no protein in it. The oil based components of soy should not pose any problems for thyroid function, as the soy isoflavones genistein and daidzein which inhibit thyroid peroxidase-catalyzed reactions essential to thyroid hormone synthesis are only found in the protein part of soy.
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