Soy - Friend or Foe?

Is Soy a health food or health concern?
Soy and soy products today are viewed as major health foods, be it infant formula foods or hormone replacement products, they are everywhere. Increased consumption among adults has been matched with increased infant consumption; about 20 to 30% of infants are now drinking soy formulas and it is replacing breast milk or cow's milk in many households. Concerns have been raised because one a naturally occurring product in soy called Genistein which belongs to the isoflavone class of flavonoids (classified as a phytoestrogen). This is a naturally occurring plant; estrogen or phytoestrogen and it can imitate the effects of estrogen in the body, something people are saying justifies the call.

Soy Infant Foods
The US Center for the Evaluation of Risks to Human Reproduction (CERHR) of the National Institute of Environmental Health Services (NIEHS) and National Toxicology Program conducted a major study on the effects of soy on infants and human production in March 2006. The study made some observations on how infant formula made of soy should be made. Soy infant formula isolate has about 90% protein. This is fortified with L-methionine, L-carnitine, and taurine. L-methionine improves the biological quality of the protein, L-carnitine is needed for the oxidation of long-chain fatty acids and taurine is an antioxidant that is a major conjugate of bile acids in infants. Carnitine and taurine are naturally found in human milk.
Fats are added with vegetable oils, corn or tapioca starch and sucrose are the carbohydrate sources. This is further fortified with phosphorus, calcium, iron and zinc. These infant foods are usually fed to babies who are allergic to dairy products or are intolerant of lactose , galactose or cow's milk protein. Sometimes it is used as a vegetarian alternative or because of the "perceived" health benefits of soy. It was found that soy formula powders and liquid concentrates had more isaflavones. The quantity of genistein and daidzein were also higher than in human or cow's milk

Foe or friend
The good news is that the panel found a "negligible concern" in neonates and infants who are fed on soy formula foods. Studies on rats and humans suggest that there is no need for concern and it safe for infants who cannot be breast-fed and cannot tolerate cow's milk.
The report however brought to the fore concerns about soy-induced thyroid toxicity. There is concern that individuals with hypothyroidism may be susceptible to thyroid problems or that it may interfere with the medications used to treat the condition. However epidemiologic studies suggested no association between phytoestrogen exposure through soy consumption and thyroid cancer risk in humans.
The study also stated that people in Japan had been consuming soy products without side effects. However, it also stated that incidents of lower cardiovascular disease, cancer and postmenopausal symptoms could be attributed to the lifestyle and genetic disposition of the people of the region
Should soy be part of our diet? Should it be eaten only if it is prepared the traditional way? The debate still rages on and the health benefits are still being studied. However, there are many vegetarians and vegans who swear by it and extol its many health virtues and for the moment this food gets the thumbs up.