生物谷报道：糖尿病是一种非常复杂的综合症，通常分为I型和II型糖尿病，而其中以II型糖尿病常见。通常，医生常常建议II型糖尿病患者少吃糖。但是近年来，这种传统的建议受到了一些研究人员的质疑。这些研究人员人物，摄入适量的糖对糖尿病患者是安全的。
现在，一项新的研究证实，增加了每日糖摄入量、维持稳定的体重的患者，其血糖没有不利的变化。这项研究由英国伦敦Hammersmith医院营养学系进行。研究人员给九个体重超标的II型糖尿病患者的每日饮食增加了三片胡萝卜蛋糕（carrot cake，生物谷注），总共食用了24天。这些蛋糕被均匀地分配在每日的饮食种。研究人员在试验的之前和之后测试记录了几项指标，包括患者体重、血糖水平、胆固醇水平和胰岛素活性。
胡萝卜蛋糕是其中加有胡萝卜丝的蛋糕，味道极佳。在美国，有时人们称这种蛋糕为华盛顿的胡萝卜蛋糕。这是因为，胡萝卜蛋糕是美国第一任总统华盛顿非常喜欢吃的食品，其次是因为在1783年11月25日英国军队从纽约市撤走的日子，华盛顿进入纽约曼哈顿后所吃的食物之一就是胡萝卜蛋糕。为表示对这位开国元勋的敬意，人们把胡萝卜蛋糕与华盛顿的名字连在了一起。
领导这项研究的Gary Frost教授解释说，这些患者的能量摄入与其体重相平衡，并且他们的蔗糖摄入平均分配在一天中。相应地，他们的体重没有增加，在研究结束后的血糖水平业没有增加。另外，他们的胆固醇水平和胰岛素活性水平也没有变化。研究人员表示，这种小的、短期的研究支持了有关适量摄入糖不影响II型糖尿病的观点。
其他的一些研究证实，蔗糖的摄入可能有助于降低脂肪的摄入，从而对整体健康有力。另外，美国哈佛大学公共卫生学院研究人员发现，多食干果或花生酱，能显著降低II型糖尿病的发病风险。
研究人员对这些年龄在24岁至59岁之间的妇女进行了长达16年的调查。在调查开始时，她们没有任何糖尿病、心血管疾病和癌症等疾病病史，但在调查期间约有3200人患上了II型糖尿病。II型糖尿病又称成人发病型糖尿病，主要由体内胰岛素相对缺乏或无法得到有效利用所导致，患者多在35岁至40岁以后发病。通常认为，高脂肪食物会增加肥胖和II型糖尿病的发病风险。
调查结果显示：那些每周5次以上、每次吃一把干果的妇女，其患II型糖尿病的风险，比极少或从不吃干果的人要低30%左右；每周5次以上、每次至少食用一大汤匙花生酱，也能使妇女的II型糖尿病发病率降低约20%。
对此，研究人员认为，尽管在人们印象中，干果属于高脂肪食物，但其中所含脂肪多属非饱和性脂肪，对机体的胰岛素敏感性等能起到有益作用，而且干果中富含纤维和蛋白质等也能促进人体的胰岛素和葡萄糖平衡。
II型糖尿病，即非胰岛素依赖型糖尿病的确实发生机制，目前仍无定论；但推测可能受遗传及饮食失节、缺乏运动、形体肥胖、情志失调、化学药物等的影响，逐渐形成的一种内分泌失衡之疾病。主要根源于胰岛之β细胞受损，致胰岛素分泌不足；或是胰岛受体障碍而不能正常利用胰岛素；甚有报告指出α细胞所分泌之高血糖素相对太高亦是原因之一。其结果则引起糖类、脂质、蛋白质之代谢失调繁乱，进而引起身体的各种症状，逐渐发生并发症。
美国阿拉巴马大学（UAB）营养科学系主任W. Timothy Garvey 教授在发表在2007年10月29日《生物化学杂志》上的最新研究称，他们发现NR4A3 和NR4A1这两个蛋白可以促使肌肉对胰岛素敏感，加速葡萄糖的摄取，从而维持正常的血糖水平。研究同时发现，在动物糖尿病模型中，两个基因表达下调，伴随胰岛素抵抗提高。
对糖尿病研究而言，新的发现提示可以以提升NR4A3和NR4A1表达或活性进行药物研发。Ga rvey表示，下一步工作将围绕可以与两个蛋白相互作用或者促进其表达的分子的筛选。(生物谷：Lily）
生物谷推荐英文原文：
Public release date: 8-Jan-2008
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Contact: Dr. Alison Boyd
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The Sugar Bureau
Carrot cake study on sugar in type 2 diabetes
New study adds to new thinking on sugar in the diabetes diet
Patients with type 2 diabetes are often advised to cut out sucrose (table sugar) all together. However, in recent years this traditional advice has been questioned by some researchers who suggest that moderate amounts of sugar can be safely consumed as part of the diet of patients with diabetes. Now a new study has been published that is consistent with this revised approach. It showed that patients who increased their daily sugar intake (in the form of carrot cake) but maintained a stable body weight, showed no adverse changes in their blood glucose.
The study was conducted by the Department of Nutrition and Dietetics at London抯 Hammersmith Hospital. Three slices of carrot cake were added to the daily diets of nine, overweight type 2 diabetes patients over 24 days (bringing their daily total to 88g or 18 teaspoons of sugar). Consumption of the carrot cake slices was evenly distributed across the day. Several measurements were recorded at the beginning and end of the study, including the patients?weight, blood sugar (glucose) levels, cholesterol levels, and insulin sensitivity (which is a measure of how well the body responds to the hormone insulin).
Professor Gary Frost, who led the study, explained 慖n this study, the energy intake of these patients was balanced to their body weight, and their sucrose intake was spread evenly over a day. Correspondingly, they did not gain weight or show an increase in blood glucose levels at the end of the study; in addition, their cholesterol levels and insulin sensitivity did not change.?He added 憈he results of this small, short-term study support other scientific studies, which suggest that there could be more flexibility with sucrose in the diets of patients with type 2 diabetes. There is evidence from other studies (reviewed by Kirk et al 2000) that inclusion of sucrose may help people to lower their fat intake, which in turn may be beneficial to overall health?
Professor Frost continued 慣his research is in line with the dietary guidelines set by the American Diabetes Association (2007), which state that sucrose does not cause a greater increase in blood glucose levels than an equivalent amount of starch. Therefore sucrose or sucrose-containing foods should be treated similarly to other carbohydrate containing foods by people with diabetes; either substituted for other carbohydrates in the total daily intake, or managed with appropriate diabetes medication.
