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Objective: This analysis was conducted to determine the efficacy of extracted or synthesized soybean isoflavones in the alleviation of hot flashes in perimenopausal and postmenopausal women. Methods: PubMed and The Cochrane Controlled Clinical Trials Register Database were searched for relevant articles reporting double-blinded randomized controlled trials through December 14, 2010. References within identified articles, as well as peer-reviewed articles that had come to the attention of the authors through other means, were also examined for suitability. This systematic review and meta-analysis, which evaluated the effects of isoflavones on the frequency, severity, or composite score (frequency severity) of hot flashes compared with placebo was conducted according to Cochrane Handbook guidelines. Results: From 277 potentially relevant publications, 19 trials (reported in 20 articles) were included in the systematic review (13 included hot flash frequency; 10, severity; and 3, composite scores), and 17 trials were selected for meta-analyses to clarify the effect of soybean isoflavones on hot flash frequency (13 trials) and severity (9 trials). Metaanalysis revealed that ingestion of soy isoflavones (median, 54 mg; aglycone equivalents) for 6 weeks to 12 months significantly reduced the frequency (combined fixed-effect and random effects model) of hot flashes by 20.6% (95% CI, j28.38 to j12.86; P G 0.00001) compared with placebo (heterogeneity P = 0.0003, I 2 = 67%; random effects model). Meta-analysis also revealed that isoflavones significantly reduced hot flash severity by 26.2% (95% CI: j42.23 to j10.15, P = 0.001) compared with placebo (heterogeneity, P G 0.00001, I 2 = 86%; random effects model). Isoflavone supplements providing more than 18.8 mg of genistein (the median for all studies) were more than twice as potent at reducing hot flash frequency than lower genistein supplements. Conclusions: Soy isoflavone supplements, derived by extraction or chemical synthesis, are significantly more effective than placebo in reducing the frequency and severity of hot flashes. Additional studies are needed to further address the complex array of factors that may affect efficacy, such as dose, isoflavone form, baseline hot flash frequency, and treatment duration.

Effects of soy isoflavones on osteoporosis remain unclear. This review aimed to clarify the effect of soy isoflavones on bone mineral density (BMD) and turnover markers in menopausal women. PubMed and the Cochrane Library were searched in July 2011 for relevant meta-analyses of randomized controlled trials evaluating effects of soy isoflavones on BMD and bone turnover markers. Three meta-analyses evaluated the effects of soy isoflavones on lumbar spine, total hip, femoral neck, and trochanter BMD. Soy isoflavones significantly improved lumbar spine BMD in a moderate manner, but did not affect total hip, femoral neck, and trochanter BMD in menopausal women. Ingestion of soy isoflavones for six months appeared to be enough to exert a beneficial effect on lumbar spine BMD. Two meta-analyses evaluated the effects of soy isoflavones on a bone resorption marker (urine deoxypyridinoline) and two formation markers (serum alkaline phosphatase and osteocalcin). Soy isoflavones significantly decreased urine deoxypyridinoline in a moderate manner, but did not affect serum alkaline phosphatase and osteocalcin in menopausal women. Soy isoflavones may prevent postmenopausal osteoporosis and improve bone strength thus decreasing risk of fracture in menopausal women by increasing lumbar spine BMD and decreasing bone resorption marker urine deoxypyridinoline. Further studies are needed to address factors affecting the magnitude of the beneficial effects of soy isoflavones and to assess the possible interactions between soy isoflavones and anti-osteoporosis drugs, and to verify effects on BMD of other skeletal sites and other bone turnover markers.

Introduction Effects of soy isoflavone supplements on bone turnover markers remain unclear. This up-to-date systematic review and meta-analysis of randomized controlled trials (RCTs) was performed primarily to more completely and precisely clarify the effects on urinary deoxypyridinoline (DPD) and serum bone alkaline phosphatase (BAP) and secondarily to evaluate the effects on other bone turnover markers, compared with placebo in menopausal women. Methods PubMed, CENTRAL, ICHUSHI, and CNKI were searched in June 2009 for relevant studies of RCTs. Data on study design, participants, interventions, and outcomes were extracted and methodological quality of each included trial was assessed. Results From 3740 identified relevant articles, 10 (887 participants), 10 (1210 participants), and 8 (380 participants) RCTs were selected for meta-analysis of effects on DPD, BAP, and serum osteocalcin (OC), respectively, using Review Manager 5.0.22. Daily ingestion of an average 56 mg soy isoflavones (aglycone equivalents) for 10 weeks to 12 months significantly decreased DPD by 14.1% (95% CI: − 26.8% to − 1.5%; P = 0.03) compared to baseline (heterogeneity: P I 2 = 93%; random effects model). The overall effect of soy isoflavones on DPD compared with placebo was a significant decrease of − 18.0% (95% CI: − 28.4% to − 7.7%, P = 0.0007; heterogeneity: P = 0.0001; I 2 = 73%; random effects model). Subgroup analyses and meta-regressions revealed that isoflavone dose and intervention duration did not significantly relate to the variable effects on DPD. Daily supplementation of about 84 mg and 73 mg of soy isoflavones for up to 12 months insignificantly increased BAP by 8.0% (95% CI: − 4.2% to 20.2%, P = 0.20; heterogeneity: P I 2 = 98%) and OC by 10.3% (95% CI: − 3.1% to 23.7%, P = 0.13; heterogeneity: P = 0.002; I 2 = 69%) compared with placebo (random effects model), respectively. Conclusions Soy isoflavone supplements moderately decreased the bone resorption marker DPD, but did not affect bone formation markers BAP and OC in menopausal women. The effects varied between studies, and further studies are needed to address factors relating to the observed effects of soy isoflavones on DPD and to verify effects on other bone turnover markers.

Kyoko Taku1, Keizo Umegaki1, Yoshiko Ishimi2, Shaw Watanabe31Information Center, National Institute of Health and Nutrition, Tokyo, Japan; 2Nutritional Epidemiology Program, National Institute of Health and Nutrition, Tokyo, Japan; 3Nutritional Education Program, National Institute of Health and Nutrition, Tokyo, JapanAbstract: When provided concurrently with soy protein for 1–3 months, soy isoflavones exert synergistic or additive cholesterol-lowering effects. This meta-analysis was performed to evaluate the effects of extracted soy isoflavones alone (not ingested concurrently with soy protein) on total and low density lipoprotein (LDL) cholesterol. MEDLINE (1966–2007), EMBASE (1966–2007), CENTRAL (1966–2007), ICHUSHI (1983–2008), and CNKI (1979–2007) were searched for randomized placebo-controlled trials published in English, Japanese, and Chinese, describing the changes in lipid profiles in adult humans resulting from ingestion of extracted soy isoflavones for 1–3 months. Reference lists of relevant systematic reviews and meta-analyses were hand-searched. Meta-analysis of 10 and 9 trials with usable information using REVMAN found that an average of 70 mg soy isoflavones/day (27–132 mg, as the aglycone form) alone had a nonsignificant effect on total (0.01 mmol/L [95% CI: –0.12, 0.14]; P = 0.86) and LDL (0.03 mmol/L [95% CI: –0.11, 0.16]; P = 0.71) cholesterol in menopausal women, respectively. It is concluded that ingestion of about 70 mg extracted soy isoflavones/day alone for 1–3 months does not improve total and LDL cholesterol levels in normocholesterolemic menopausal women; further studies are needed to verify the effects of extracted soy isoflavones.Keywords: extracted soy isoflavones, lipid, total cholesterol, LDL cholesterol

Clinical trials have reported the cholesterol-lowering effects of soy protein intake, but the components responsible are not known.This meta-analysis was primarily conducted to evaluate the precise effects of soy isoflavones on lipid profiles. The effects of soy protein that contains enriched and depleted isoflavones were also examined.PUBMED was searched for English-language reports of randomized controlled trials published from 1990 to 2006 that described the effects of soy protein intake in humans. Eleven studies were selected for the meta-analysis.Soy isoflavones significantly decreased serum total cholesterol by 0.10 mmol/L (3.9 mg/dL or 1.77%; P = 0.02) and LDL cholesterol by 0.13 mmol/L (5.0 mg/dL or 3.58%; P0.0001); no significant changes in HDL cholesterol and triacylglycerol were found. Isoflavone-depleted soy protein significantly decreased LDL cholesterol by 0.10 mmol/L (3.9 mg/dL or 2.77%; P = 0.03). Soy protein that contained enriched isoflavones significantly decreased LDL cholesterol by 0.18 mmol/L (7.0 mg/dL or 4.98%; P0.0001) and significantly increased HDL cholesterol by 0.04 mmol/L (1.6 mg/dL or 3.00%; P = 0.05). The reductions in LDL cholesterol were larger in the hypercholesterolemic subcategory than in the normocholesterolemic subcategory, but no significant linear correlations were observed between reductions and the starting values. No significant linear correlations were found between reductions in LDL cholesterol and soy protein ingestion or isoflavone intakes.Soy isoflavones significantly reduced serum total and LDL cholesterol but did not change HDL cholesterol and triacylglycerol. Soy protein that contained enriched or depleted isoflavones also significantly improved lipid profiles. Reductions in LDL cholesterol were larger in hypercholesterolemic than in normocholesterolemic subjects.

近年，世界各国において補完代替医療 (CAM) を利用する癌患者が増えている．中国の多くの病院では中西医結合療法（西洋医療と伝統中国医療 (TCM) との併用）で癌を治療・予防し，多大な成果を挙げている．本研究では，中国語文献データベースから中国で行われた癌の中西医結合療法を検証した無作為化比較試験 (RCT) を調査しシステマティックレビューした．中国語学術雑誌に掲載された論文は国家科学技術図書文献センターが提供しているデータベース (http://www.nstl.gov.cn) を用いて検索した．限定的な条件で検索した結果から，14 報の RCT を特定しレビューした．ほぼ全ての研究では西洋医療に比べ，伝統中国医療との併用は良い結果が得られていた．日本において根拠に基づく CAM を推進するために，中国などで多く行われた CAM に関する RCT から，科学的根拠を収集・評価し，データベース化する必要があると思われる．これから，CAM のメタ分析など科学的な評価手法の開発及び確立が迫られる．

To evaluate the effect of treatment with β-conglycinin, a major soyabean protein, on blood lipids in menopausal women, we recruited 100 hyperlipidaemic women aged 40–60 years old. Participants were randomly allocated to three groups: placebo group (n 34, four casein tablets/d); low dose group (n 33, four tablets containing 2·3 g β-conglycinin/d); high-dose group (n 33, eight tablets containing 4·6 g β-conglycinin/d). The mean serum TAG concentration was significantly reduced after 6 and 12 weeks of β-conglycinin intervention by 0·44 (sd 0·20) and 0·78 (sd 1·03) mmol/l in the low-dose group, and by 0·46 (sd 0·17) and 1·25 (sd 1·06) mmol/l in the high-dose group, respectively. One-way ANOVA revealed that serum TAG concentrations in the low-dose and high-dose groups were significantly lowered compared with the placebo group at weeks 6 and 12 (Psd 0·72) and 0·52 (sd 0·97) mmol/l at week 12, respectively (PP

Reported effects of different soy products on blood pressure vary. This systematic review and meta-analysis was performed to clarify the effects of soy isoflavone extract supplements on systolic and diastolic blood pressure (SBP and DBP) in adult humans.PubMed, CENTRAL, ICHUSHI, and CNKI were searched in June 2009 for relevant randomized placebo-controlled trials. Study data and indicators of methodological validity were independently extracted by two authors using predefined data fields. Meta-analysis was carried out in Review Manager 5.0.22.Searches identified 3740 articles, of which 14 randomized controlled trials (789 participants) were included. Daily ingestion of 25-375 mg soy isoflavones (aglycone equivalents) for 2-24 weeks significantly decreased SBP by 1.92 mmHg (95% confidence interval -3.45 to -0.39; P = 0.01) compared with placebo (heterogeneity P = 0.39, fixed effect model) in adults with normal blood pressure and prehypertension. The effect was not lost on sensitivity analysis. Subgroup analyses suggest greater effects in studies longer than 3 months, in Western populations, at lower doses, and in studies at lower risk of bias. Soy isoflavones did not affect DBP [-0.13 (95% confidence interval -1.03 to 0.78) mmHg, P = 0.78; heterogeneity P = 0.20, fixed effect model].Soy isoflavone extracts significantly decreased SBP but not DBP in adult humans, and no dose-response relationship was observed. Further studies are needed to address factors related to the observed effects of soy isoflavones on SBP and to verify the effect in hypertensive patients.