生物通報(bào)道：根據(jù)12月18日在Journal of Clinical Endocrinology & Metabolism雜志上發(fā)表的一項(xiàng)研究表明，采用番茄豐富的飲食，可保護(hù)絕經(jīng)后婦女免受乳腺癌的危害。

在絕經(jīng)后婦女中，乳腺癌的風(fēng)險(xiǎn)增加，因?yàn)樗齻兊纳眢w質(zhì)量指數(shù)上升。但是仍然缺乏實(shí)用的預(yù)防方法來(lái)降低乳腺癌風(fēng)險(xiǎn)。關(guān)于類胡蘿卜素和大豆異黃酮對(duì)絕經(jīng)后婦女循環(huán)脂肪因子影響的調(diào)查研究還很少。本項(xiàng)研究發(fā)現(xiàn)，富含番茄的飲食，對(duì)在脂肪和糖代謝調(diào)節(jié)中發(fā)揮作用的激素水平，具有積極的影響。

本研究的第一作者、美國(guó)羅格斯大學(xué)流行病學(xué)助理教授Adana Llanos博士說(shuō)：“我們的研究結(jié)果表明，大量食用番茄和以番茄為原料的食品，即使在很短的時(shí)間內(nèi)，也具有非常明顯的優(yōu)勢(shì)。”當(dāng)Llanos還是俄亥俄州立大學(xué)綜合癌癥中心Electra Paskett教授的博士后時(shí)，完成了這項(xiàng)研究工作。她說(shuō)：“水果和番茄富含必需的營(yíng)養(yǎng)素、維生素、礦物質(zhì)和植物化學(xué)物（例如番茄紅素），食用它們，具有顯著的益處。基于這項(xiàng)數(shù)據(jù)，我們認(rèn)為，定期食用至少每日推薦分量的水果和蔬菜，能夠促進(jìn)高危人群的乳腺癌預(yù)防。”

這項(xiàng)縱向交叉研究，在一組70歲絕經(jīng)后婦女中，分別檢測(cè)了富含番茄和大豆的飲食對(duì)她們的影響。連續(xù)10周，這些婦女每天食用番茄紅素含量至少為25毫克的番茄產(chǎn)品。在另外一個(gè)單獨(dú)的10周周期中，受試者每天至少食用40克的大豆蛋白。在每個(gè)測(cè)試周期開(kāi)始之前，她們分別都被要求在兩周時(shí)間內(nèi)放棄吃番茄和大豆制品。

當(dāng)受試者遵循富含番茄的飲食時(shí)，她們的脂聯(lián)素——參與糖和脂肪水平調(diào)節(jié)的一種激素——水平上升了9%。具有較低身體質(zhì)量指數(shù)的女性，這種效果略強(qiáng)。

Llanos說(shuō)：“這項(xiàng)研究證明了預(yù)防肥胖的重要性。采用富含番茄的飲食，對(duì)體重保持健康的女性的激素水平，具有較大的影響。”

大豆飲食與受試者脂聯(lián)素水平的下降有關(guān)。研究人員最初推理，包含大量大豆的飲食，可能是亞洲女性具有比美國(guó)女性更低的乳腺癌發(fā)病率的部分原因，但是Llanos說(shuō)，任何有利的影響，都局限于特定的種族。（生物通：王英）

生物通推薦原文摘要：
Effects of Tomato and Soy on Serum Adipokine Concentrations in Postmenopausal Women at Increased Breast Cancer Risk: A Cross-Over Dietary Intervention Trial
Abstract
Context: Breast cancer risk among postmenopausal women increases as body mass index increases. Practical preventive methods to reduce risk of breast cancer are lacking. Few studies have investigated the effects of carotenoids and isoflavones on circulating adipokines in postmenopausal women.

Objective: The aim was to examine the effects of lycopene- and isoflavone-rich diets on serum adipokines.

Design: This was a 26-week, two-arm, longitudinal crossover trial.

Setting: Participants were recruited from clinics at The Ohio State University Comprehensive Cancer Center.

Participants: Seventy postmenopausal women at increased breast cancer risk participated in the study. The mean age and body mass index of participants was 57.2 years and 30.0 kg/m2, respectively; the study was comprised of 81.4% whites.

Interventions: The interventions included 10 weeks of consumption of a tomato-based diet (≥25 mg lycopene daily) and 10 weeks of consumption of a soy-based diet (≥40 g of soy protein daily), with a 2-week washout in between.

Main Outcome Measures: Changes in serum adiponectin, leptin, and the adiponectin to leptin ratio were examined for each intervention through linear mixed models, with ratio estimates corresponding to postintervention adipokine concentrations relative to preintervention concentrations.

Results: After the tomato intervention, among all women, adiponectin concentration increased (ratio 1.09, 95% confidence interval (CI) 1.00–1.18), with a stronger effect observed among nonobese women (ratio 1.13, 95% CI 1.02–1.25). After the soy intervention, adiponectin decreased overall (ratio 0.91, 95% CI 0.84–0.97), with a larger reduction observed among nonobese women (ratio 0.89, 95% CI 0.81–0.98). Overall, no significant changes in leptin or the adiponectin to leptin ratio were observed after either intervention.

Conclusions: Increasing dietary consumption of tomato-based foods may beneficially increase serum adiponectin concentrations among postmenopausal women at increased breast cancer risk, especially those who are not obese. Additional studies are essential to confirm these effects and to elucidate the specific mechanisms that may make phytonutrients found in tomatoes practical as breast cancer chemopreventive agents.