Naked Science Forum

Life Sciences => Physiology & Medicine => Topic started by: cjsussman on 29/04/2011 20:01:02

Title: Does drinking soya milk affect the thyroid?
Post by: cjsussman on 29/04/2011 20:01:02

C J Sussman  asked the Naked Scientists:
   
What is the effect of drinking soya milk on the body? I have heard it suppresses the thyroid gland and prevents the absorption of calcium and iron, which causes anaemia. Does it block the absorption of a thyroid supplement called eltroxin?  

Thanks and  regards,

Cecil

What do you think?

Title: Does drinking soya milk affect the thyroid?
Post by: LGarton on 05/05/2011 15:03:58

Soya foods have been a staple in the diets of many Asian countries for centuries without negative effects on health,on the contrary many diseases are vastly less common in these countries - including heart disease, diabetes and cancer. The safety of soya foods has been thoroughly reviewed by a number of independent organisations in recent years and none of these scientific bodies have suggested that they are unsafe/ unsuitable for consumption by the general population.

A recent review of the available studies in thyroid function(ref: Messina & Redmond 2006 Effects Soy Protein and Soybean Isoflavones on Thyroid Function in Healthy Adults and Hypothyroid Patients: A Review of the Relevant Literature. Thyroid Vol 16: No 3 pg 249-257)confirms that soya does not adversely affect thyroid function.

Concerning the combination of thyroid medication and soya, the absorption of the medication could be influenced as is also the case with fibre intake;  a degree of separation between taking medication and eating soya foods is suggested to minimize any possible interaction. So there is no reason to avoid soya foods.  Adequate dietary intake of iodine amongst soya consumers is also important

Also soya beans, like other legumes, contain phytates which has been suggested to inhibit iron and calcium absorption . A recent SACN report (Iron and health 2011) has shown that when consumed within the whole diet, current recommendation is that inhibitors such as phytates do not significantly effect iron status. Due to processing, soya foods have a much lower phytate content compared to whole soya beans. Many soya foods such as milk alternatives are now fortified with calcium to a level comparable to dairy, and can therefore make a valuable contribution to a persons calcium intake particularly if following a dairy free diet

Lynne Garton BSc (Hons), RD
Dietitian and Nutrition Consultant

Title: Does drinking soya milk affect the thyroid?
Post by: cjsussman on 07/05/2011 11:49:04

Thank you.

Your response was most encouraging and beneficial.

C J [:)] Sussman