FIBRE AND DIABETES
People with diabetes are usually encouraged to include more fibre-rich foods in their diet. The importance of this has been confirmed in a recently published systematic review and meta-analysis looking at the role of dietary fibre and whole grains in diabetes management.
The scientists combined the findings of 44 studies involving people with type 1 diabetes, type 2 diabetes and prediabetes. This included two prospective cohort studies (which follow groups of people over time and compare them for different outcomes) and 42 controlled trials (where people are allocated to different treatment groups and the outcomes of those treatments are compared). Some studies used high fibre foods and others used fibre supplements.
The cohort studies showed a reduction in premature death in those eating a higher fibre diet, with a clear dose response, meaning that as fibre intake increased, the risk of death decreased. The controlled trials that included between 433 and 1807 people, found that increasing fibre intake resulted in improvements in blood glucose levels, blood fats (cholesterol and triglyceride), body weight and measures of inflammation. However, in this systematic review, no differences were seen between different types of fibre or the source of the fibre (food or supplements), most likely due to the smaller number of people included. There are of course other benefits of getting most of your fibre from a wide diversity of plant foods, particularly for your gut microbiome.
High fibre foods, such as wholegrains, legumes, fruit and starchy vegetables, are also often rich in available carbohydrate (e.g., starches and sugars). But despite some people advocating low carb diets for diabetes management and weight loss, the authors of this paper found no evidence to suggest that relatively high intake of these carbohydrate-rich foods negatively affect blood glucose or weight management.
Based on their findings, the authors recommend that people with diabetes or prediabetes should increase their fibre intake to at least 35g per day. Considering the average Australian adult only consumes around 23g per day, and intakes are even lower in most other developed nations, this means increasing fibre intake by at least one-third.
A good place to start would be aiming for your ‘2 and 5’ fruit and veg each day. Switching refined grains (such as white bread and highly processed low fibre breakfast cereals) to wholegrains (such as dense grainy breads and traditional rolled oats) and incorporating legumes (lentils, chickpeas and dried/canned beans) into your meals regularly are also great ways help to boost fibre intake.
References:
- Reynolds and colleagues. Dietary fibre and whole grains in diabetes management: Systematic review and meta-analyses. PLoS Med. 2020.
- Heiman and Greenway. A healthy gastrointestinal microbiome is dependent on dietary diversity. Mol Metab. 2016.
Kate Marsh is an is an Advanced Accredited Practising Dietitian, Credentialled Diabetes Educator and health and medical writer with a particular interest in plant-based eating and the dietary management of diabetes and polycystic ovary syndrome (PCOS).
Contact: Via her website www.drkatemarsh.com.au.