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Lack of Joy with Soy
There is an increasing trend of putting soya in everything from bread and breakfast cereals to ice-cream and, of course, low-carb 'diet' products. High in protein, and very abundant and cheap, it looks like a good food to include in other foods. But, while fermented soya is okay, unfermented soya is not. And it is the unfermented soya that is used in these products today. Put bluntly, soya protein powders, soya flour, soya oil and soya milk, and foods containing them, should carry a health warning as cigarettes do. Here's why:
1. Soya prevents weight loss.
Most people go on any diet to lose weight. But soya powerfully suppresses the thyroid and lowers metabolic rate. (1) The thyroid gland produces hormones that have a profound effect on our bodies' metabolism ? the rate at which our bodies use energy. This in turn has implications for the cause and treatment of obesity. It also affects such seemingly unrelated things as blood cholesterol levels. Twenty-five grams of soya protein isolate contains 50 - 70 mg of isoflavones. Yet it took only 45 mg of isoflavones in premenopausal women to exert significant biological effects, including a reduction in hormones needed for adequate thyroid function. These effects continued for three months after they stopped eating the soya. (2) A lower metabolic rate makes weight gain more likely and weight loss more difficult. Thus soya is the last thing anyone who is concerned about their weight should eat.
2. Soya inhibits protein absorption.
Soya contains protease inhibitors that block the action of trypsin and other enzymes needed for protein digestion. These produce serious gastric distress and reduce protein digestion to cause chronic deficiencies in amino acid uptake. In test animals, diets high in trypsin inhibitors cause enlargement and pathological conditions of the pancreas, including cancer. (3)
3. Soya upsets hormones.
Soya also decreases female reproductive hormones: oestrone, LS and FSH. (4) And causes menstrual disturbances in premenopausal women.(5) In 1992 the Swiss health service estimated that 100 grams of soya protein provided the oestrogenic equivalent of the Pill.(6) And with that in mind, what of its effects on children and men?
4. Soya harms children.
Isoflavones in infancy are probably the greatest cause for concern as they are likely to affect the way a child develops. Soya consumption has been linked to numerous disorders, including infertility, increased cancer and infantile leukaemia, and studies dating back to the 1950s showed that genistein in soya caused disrupted hormone production in animals. (7) Laboratory studies also suggest that isoflavones inhibit synthesis of oestradiol and other steroid hormones. Several species of animals including mice, cheetah, quail, pigs, rats, sturgeon and sheep displayed reproductive problems, infertility, thyroid disease and liver disease due to dietary isoflavones. In 1998, investigators reported that circulating concentrations of isoflavones in infants fed soya-based baby formula were 13,000 to 22,000 times higher than plasma oestradiol concentrations in infants fed baby formula made with cow's milk. (8) Infants fed soya milk or other soya products may develop hormone abnormalities such as delayed genital formation in boys and early menstruation in girls. (8). An infant exclusively fed on soya formula receives the oestrogenic equivalent (based on body weight) of at least five birth control pills per day. (9) By contrast, almost no phytoestrogens have been detected in dairy-based infant formula or in human milk.
5. Soya increases cancer risk.
Soya increases the growth rate of breast cancer cells.(10) Soya increases progesterone activity and more breast cell growth in menstruating women. (11). And some researchers believe the rapid increase in liver and pancreatic cancer in Africa is due to the introduction of soya products there.(12)
6. Soya ulcerates the gut.
Pigs in the USA fed soya in their diets were found to have hopelessly ulcerated intestines. Advice from the US soya industry's website advised farmers to strictly limit soya fed to pigs. (13) Although no human trials have been done for ethical reasons, there is no reason to suppose the same will not happen in humans.
7. Soya increases risk of deficiency diseases.
Lastly, soya beans have one of the highest phytic acid levels of any grain or legume that has been studied.[14] This is important because phytic acid binds with minerals to form phytates that are not absorbed from the intestine. This leads to a wide range of nutritional deficiency diseases. The mineral most affected by soya is zinc. (14) Soya-based infant formula is particularly harmful because zinc is needed for proper development and functioning of the brain and nervous system. It also plays a role in protein synthesis and collagen formation; it is involved in the blood-sugar control mechanism and thus protects against diabetes; it is needed for a healthy reproductive system. Zinc is a key component in numerous vital enzymes and plays a role in the immune system.
The current dramatic increases in obesity, diabetes, cancers, heart disease, etc, are a direct result of policies emanating from the USA. This present wave of low-carb dietary advice and 'low-carb' products, aimed at undoing the previous harm, also comes mainly from the USA. And, as I hope I have shown above, the 'foods' used are just as unhealthy.
What is the point in swapping one disease for another?
There is, however, a much better way. It was pioneered by a Londoner, William Banting, in 1863. Indeed it was this regime that formed the basis for all other present low-carb diets, including Atkins.
Banting's low-carb dietary regime has a century of epidemiological evidence and clinical trials supporting it. It doesn't rely on the unhealthy products that Atkins does, but on natural, real foods. Correctly constituted, it is completely healthy, it works and it's safe.
Why not ditch US pseudo-foods and eat the much more natural and healthy British way? Make no mistake — if you domn't eat real food, the shops will stop selling it. And once it has gone, it will be very difficult to get it back again.
References
1.Ishuzuki Y, et al. The effect on the thyroid gland of soy beans administered experimentally in healthy subjects. Nippon Naihunpi gakkai Zasshi 1991; 67: 622-9.
2. Cassidy A, et al. Biological Effects of a Diet of Soy Protein Rich in Isoflavones on the Menstrual Cycle of Premenopausal Women. American Journal of Clinical Nutrition 1994; 60: 333-340.
3. Rackis JJ, et al. The USDA trypsin inhibitor study. I: Background, objectives and procedural details. In Qualification of Plant Foods in Human Nutrition. vol. 35, 1985.
4. Duncan AM, et al. Soy isoflavones exert modest effects in premenopausal women. Journal of Endocrinologic Metabolism 1999; 84: 192-7.
5. Benson JE, et al. Nutritional aspects of amenorrhea in the female athlete. Triad International Journal of Sports Medicine 1996; 134-45.
6. Bulletin de L'Office Fédéral de la Santé Publique, No. 28, 20 July 1992
7. Matrone G, et al. Effect of Genistin on Growth and Development of the Male Mouse. Journal of Nutrition 1956; 235-240
8. Setchell KD, et al. Isoflavone content of infant formulas and the metabolic fate of these early phytoestrogens in early life. American Journal of Clinical Nutrition 1998; Supplement: 1453S-1461S
9. Irvine C, et al. The Potential Adverse Effects of Soybean Phytoestrogens in Infant Feeding. NZ Medical Journal 1995; 24: 318
10. Hseih CY, et al. Estrogenic effects of genistein on the growth of estrogen receptor positive human breast cancer (MCF-7) cells in vitro and in vivo. Cancer Research 1998; 58: 3833-8
11. McMichael-Phillips DF, et al. Effects of soy-protein supplementation on epithelial proliferation in the histologically normal human breast. American Journal of Clinical Nutrition 1998; 68 (6 Suppl): 1431S-5S
12. Katz SH. Food and Biocultural Evolution: A Model for the Investigation of Modern Nutritional Problems. In Nutritional Anthropology. Alan R. Liss Inc., 1987, p. 50
13. http://www.centralsoya.com "Soya protein content for animal feed".
14. El Tiney AH. Proximate Composition and Mineral and Phytate Contents of Legumes Grown in Sudan. Journal of Food Composition and Analysis 1989; 2: 6778.
15. A summary of the many effects of phytic acid on zinc absorption can be found in: Leviton, Richard. Tofu, Tempeh, Miso and Other Soyfoods: The 'Food of the Future' — How to Enjoy Its Spectacular Health Benefits. Keats Publishing, Inc., New Canaan, CT, USA, 1982
Last updated 22 January 2013
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