Priebe M G, van Binsbergen J J, de Vos R, Vonk R J
University Medical Centre Groningen (UMCG), Department of Medical Biomics, Laboratory Nutrition and Metabolism, Antonius Deusinglaan 1, Building 3215 4th floor, Groningen, Netherlands, 9713 AV.
Cochrane Database Syst Rev. 2008 Jan 23;2008(1):CD006061. doi: 10.1002/14651858.CD006061.pub2.
Diet as one aspect of lifestyle is thought to be one of the modifiable risk factors for the development of type 2 diabetes mellitus (T2DM). Information is needed as to which components of the diet could be protective for this disease.
To asses the effects of whole-grain foods for the prevention of T2DM.
We searched CENTRAL, MEDLINE, EMBASE, CINAHL and AMED.
We selected cohort studies with a minimum duration of five years that assessed the association between intake of whole-grain foods or cereal fibre and incidence of T2DM. Randomised controlled trials lasting at least six weeks were selected that assessed the effect of a diet rich in whole-grain foods compared to a diet rich in refined grain foods on T2DM and its major risk factors.
Two authors independently selected the studies, assessed study quality and extracted data. Data of studies were not pooled because of methodological diversity.
One randomised controlled trial and eleven prospective cohort studies were identified. The randomised controlled trial, which was of low methodological quality, reported the change in insulin sensitivity in 12 obese hyperinsulinemic participants after six-week long interventions. Intake of whole grain foods resulted in a slight improvement of insulin sensitivity and no adverse effects. Patient satisfaction, health related quality of life, total mortality and morbidity was not reported. Four of the eleven cohort studies measured cereal fibre intake, three studies whole grain intake and two studies both. Two studies measured the change in whole grain food intake and one of them also change in cereal fibre intake. The incidence of T2DM was assessed in nine studies and changes in weight gain in two studies. The prospective studies consistently showed a reduced risk for high intake of whole grain foods (27% to 30%) or cereal fibre (28% to 37%) on the development of T2DM.
AUTHORS' CONCLUSIONS: The evidence from only prospective cohort trials is considered to be too weak to be able to draw a definite conclusion about the preventive effect of whole grain foods on the development of T2DM. Properly designed long-term randomised controlled trials are needed. To facilitate this, further mechanistic research should focus on finding a set of relevant intermediate endpoints for T2DM and on identifying genetic subgroups of the population at risk that are most susceptible to dietary intervention.
饮食作为生活方式的一个方面，被认为是2型糖尿病（T2DM）发病的可改变风险因素之一。我们需要了解饮食中的哪些成分可能对这种疾病具有保护作用。
评估全谷物食品对预防T2DM的作用。
我们检索了Cochrane系统评价数据库、MEDLINE、EMBASE、护理学与健康领域数据库（CINAHL）和澳大利亚医学文献数据库（AMED）。
我们选择了至少持续五年的队列研究，这些研究评估了全谷物食品或谷物纤维摄入量与T2DM发病率之间的关联。我们还选择了至少持续六周的随机对照试验，这些试验评估了富含全谷物食品的饮食与富含精制谷物食品的饮食相比，对T2DM及其主要风险因素的影响。
两位作者独立选择研究、评估研究质量并提取数据。由于方法学的多样性，未对研究数据进行合并。
确定了一项随机对照试验和十一项前瞻性队列研究。该随机对照试验的方法学质量较低，报告了12名肥胖高胰岛素血症参与者在为期六周的干预后的胰岛素敏感性变化。摄入全谷物食品可使胰岛素敏感性略有改善，且无不良影响。未报告患者满意度、健康相关生活质量、总死亡率和发病率。十一项队列研究中有四项测量了谷物纤维摄入量，三项研究测量了全谷物摄入量，两项研究同时测量了两者。两项研究测量了全谷物食品摄入量的变化，其中一项还测量了谷物纤维摄入量的变化。九项研究评估了T2DM的发病率，两项研究评估了体重增加的变化。前瞻性研究一致表明，高摄入全谷物食品（27%至30%）或谷物纤维（28%至37%）可降低患T2DM的风险。
仅来自前瞻性队列试验的证据被认为过于薄弱，无法就全谷物食品对T2DM发病的预防作用得出明确结论。需要设计合理的长期随机对照试验。为便于开展此类试验，进一步的机制研究应侧重于寻找一组与T2DM相关的中间终点，并确定最易受饮食干预影响的高危人群遗传亚组。
