Article

Whole grain foods for the prevention of type 2 diabetes mellitus

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 of systematic reviews (Online) (Impact Factor: 5.94). 02/2008; DOI: 10.1002/14651858.CD006061.pub2
Source: PubMed

ABSTRACT 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.
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.

0 Bookmarks
 · 
85 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The Mediterranean diet (MD) is considered one of the healthiest dietary models. Many of the characteristic components of the MD have functional features with positive effects on health and wellness. The MD adherence, calculated through various computational scores, can lead to a reduction of the incidence of major diseases (e.g., cancers, metabolic and cardiovascular syndromes, neurodegenerative diseases, type 2 diabetes and allergy). Furthermore, eating habits are the main significant determinants of the microbial multiplicity of the gut, and dietary components influence both microbial populations and their metabolic activities from the early stages of life. For this purpose, we present a study proposal relying on the generation of individual gut microbiota maps from MD-aware children/adolescents. The maps, based on meta-omics approaches, may be considered as new tools, acting as a systems biology-based proof of evidence to evaluate MD effects on gut microbiota homeostasis. Data integration of food metabotypes and gut microbiota "enterotypes" may allow one to interpret MD adherence and its effects on health in a new way, employable for the design of targeted diets and nutraceutical interventions in childcare and clinical management of food-related diseases, whose onset has been significantly shifted early in life.
    International Journal of Molecular Sciences 07/2014; 15(7):11678-99. DOI:10.3390/ijms150711678 · 2.46 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Intake of wholegrain foods has been associated in large prospective cohort studies with decreased rates of diseases such as type 2 diabetes, ischaemic heart disease and hypertension. Multiple mechanisms for the protectiveness of wholegrain foods have been reported. Health authorities in western countries recommend wholegrains as one of the major food sources in a healthy diet, otherwise rich in vegetables, legumes and low-fat dairy. However, the existing evidence for the intake of wholegrains is highly subject to confounding. Many of the results seen in the prospective cohort studies have not been borne out in randomised controlled trials or good-quality meta-analyses. The recommended intake of wholegrains suggested in some countries is well above what there is evidence for. Products labelled wholegrain have variable quantities of the intact grain and differ widely in their effect on blood glucose. Excessive quantities may add to glycaemic load, and anti-nutrients in wholegrains may have adverse health consequences. With the rate of diabetes and obesity increasing, some researchers have questioned the role of grains as part of a healthy diet. Palaeolithic diets, those that are more in keeping with our evolutionary legacy, contain no grains or dairy, but are rich in vegetables, meat, fish and eggs, with the inclusion of some tubers. Smaller trials in animals and humans comparing a palaeolithic diet to a grain-based diet show improved metabolic profiles in the former.
    Food and Nutrition Sciences 01/2012; 03(08). DOI:10.4236/fns.2012.38152
  • [Show abstract] [Hide abstract]
    ABSTRACT: Assessment of design heterogeneity conducted prior to meta-analysis is infrequently reported; it is often presented post hoc to explain statistical heterogeneity. However, design heterogeneity determines the mix of included studies and how they are analyzed in a meta-analysis, which in turn can importantly influence the results. The goal of this work is to introduce ways to improve the assessment and reporting of design heterogeneity prior to statistical summarization of epidemiologic studies.
    07/2014; 3(1):80. DOI:10.1186/2046-4053-3-80
    This article is viewable in ResearchGate's enriched format