Fibre lowers chronic diseases risk -
Embargoed until 12.30pm NZT Friday 11 January
An Otago-led systematic review published in The Lancet finds people with a diet high in fibre and whole grains have lower rates of a range of chronic diet-related diseases.
Rates of heart disease - including death, colon cancer and type 2 diabetes were lower in people who eat at least 25g of fibre each day - and benefits increased with intake. The study, which looked at 40 years of data, aimed to inform new global recommendations on fibre intake. The benefits were less clear from eating foods with a low glycaemic index and glycaemic load.
The SMC asked experts to comment on the
review, which is available on Scimex for registered
journalists. Feel free to use these comments in your
Dr Elaine Rush, Professor of Nutrition, Auckland University of Technology, comments:
"A substantial body of evidence from 185 prospective studies and 58 clinical trials show that high compared with low intakes of dietary fibre are associated with a 15-30 per cent decrease in all-cause and cardiovascular mortality and have beneficial effects on lowering body weight, systolic blood pressure and cholesterol.
"This research presents a substantial body of evidence that we should be eating more whole plants to delay dying and reduce disease. Dietary fibres are constituents of all plants. Animal products including meat and dairy DO NOT contain fibre. Whole grains, commonly consumed by and easily available to New Zealanders at a reasonable price and will store well include whole grain wheat, corn kernels (tinned), brown rice and oats. Uncooked, every 100g of these foods contains more than 10g of dietary fibre. We also need to eat more vegetables and fruit and legumes such as peas, beans and lentils.
"From New Zealand, we export enough edible plants to more than feed the population adequately three or more times over what they need. The argument, for eating more plants and a variety of wholesome foods, that really matters for our future children, is that it will also help reduce carbon emissions and improve water supplies – and keep our planet healthier and inhabitable.
"It is not easy to increase fibre in the
diet. An example of how we could achieve 25 to 29 grams of
fibre a day is to eat:
- half a cup of rolled oats (9g fibre),
- 2 weetbix (3g),
- 1 thick slice of wheatmeal bread (2g),
- 1 cup of cooked lentils (4g)
- a potato cooked with the skin on (2g),
- half a cup of silverbeet (1g),
- a carrot (3g),
- an apple with the skin on (4g)."
No conflicts of
Dr Kathryn Bradbury, Nutritional Epidemiologist, University of Auckland, comments:
"This comprehensive article presents a series of systematic reviews on carbohydrate quality and chronic disease outcomes.
"The results show that there is good evidence from observational studies that higher intakes of dietary fibre are associated with a lower risk of disease, including bowel cancer and coronary heart disease. This is backed up by systematic reviews of trials, which show good evidence that higher intakes of fibre are associated with lower body weight, blood pressure and blood cholesterol.
"Likewise, there is good evidence that higher intakes of wholegrains are associated with a lower risk of bowel cancer, and lower body weight.
"These findings are particularly relevant for New Zealand, because we have one of the highest rates of bowel cancer in the world. Also, with the rise in popularity of so-called ‘Paleo’ and low carbohydrate diets, this study reminds us that dietary fibre (from fruit, vegetables and wholegrains) reduces the risk of chronic disease."
Conflict of interest statement: Professor Jim Mann was one of my PhD supervisors. I have no other conflicts of interest to declare.