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Soy 'cuts Alzheimer's risk' Tuesday, 3 April, 2001, 23:08 GMT 00:08 UK - Soy may reduce the risk of Alzheimer's disease, especially in postmenopausal women, say researchers. The discovery follows research suggesting that soy also helps reduce the risk of heart disease and cancer. A three-year animal study shows that chemicals found in soy, called phytoestrogens, appear to reduce the number of protein changes in the brain that are associated with Alzheimer's disease. Phytoestrogens mimic the action of the female sex hormone oestrogen. Oestrogen is known for its ability to reduce a woman's risk for heart disease and osteoporosis, and there is evidence that suggests it can protect against Alzheimer's disease. Researchers from the University of Alabama at Birmingham examined the impact of certain types of phytoestrogen found in soy, known as isoflavones. The study was carried out on aged female monkeys who had their ovaries removed to mimic the effects of going through the menopause. A total of 45 monkeys were fed one of three diets: * soy with isoflavones * soy without isoflavones * Premarin, a commonly prescribed oestrogen replacement for women Scientists then examined the brain tissue of three monkeys in each group for some of the protein changes that are markers of Alzheimer's disease. Lead researcher Dr Helen Kim said: "Consistent with our expectation that the soy phytoestrogens would have 'beneficial' effects, we found fewer Alzheimer's disease-linked tau protein changes in the brains of monkeys that received soy isoflavones." Improperly functioning tau proteins in the brains of people with Alzheimer's disease can cause the skeletal structure of nerve cells to collapse. The researchers also found that monkeys fed on Premarin showed less signs of tau protein malfunction. Dr Kim suspects that isoflavones and real oestrogens, such as those in Premarin, may both be beneficial for the brain. But she believes they work through different mechanisms. A health claim approved for food labels by the US Food and Drug Administration states that a daily diet containing 25 grams - two to three servings - of whole soy protein is enough to reduce the risk of heart disease. Dr Kim said: "I would expect the same levels of soy intake to translate to protection in the brain." As the population ages, Alzheimer's is becoming a growing a problem. It is estimated that nearly half of all people aged over 85 suffer from the condition. Dr Richard Harvey, director of research, Alzheimer's Society, told BBC News Online: "This research needs to be interpreted very cautiously because it is animal based and there were only a small number of animals involved in the study. "At this stage nothing from this study could be generalised to humans. "However, there is growing evidence that oestrogen and oestrogen replacement therapy for post menopausal women may have a role in reducing the risk of developing Alzheimer's disease in later life. "There are a number of large on-going clinical trials of HRT looking at this question and we wait with anticipation for the outcome of these studies." The research was presented at a meeting of the American Chemical Society. Related to this story: Alzheimer's disease (20 Dec 00 | A-B) Soya 'may reduce cancer risk' (18 Dec 00 | Health) Soya breast cancer link dismissed (05 Apr 00 | Health) Soya beans linked to developmental damage (03 Nov 99 | Health) Soya cuts cancer threat of HRT (26 Jan 99 | Health) Internet links: Alzheimer's Society American Chemical Society Talksoy.com BBC News Online: Health http://news.bbc.co.uk/low/english/health/newsid_1257000/1257583.stm janet paterson, an akinetic rigid subtype, albeit perky, parky PD: 54/41/37 CD: 54/44/43 TEL: 613 256 8340 EMAIL: [log in to unmask] "A New Voice" home page: http://www.geocities.com/janet313/ . "New Voice News" latest posts: http://groups.yahoo.com/group/nvnNET/ . ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn