According to the National Health and Medical Research Council (NHMRC) in their recommendations for nutrient reference values, the daily fibre intake for adult women should be at least 25g a day, and at least 30g for men. There are good reasons to aim for 30g or even higher if you can. High-fibre diets can help prevent bowel problems such as constipation, irritable bowel syndrome and even cancers.
The NHMRC also suggests that by increasing fibre intake to 38g per day for men and 28g per day for women, there may be further reduction of the risk of developing chronic conditions such as heart disease and diabetes.
Fibre (sometimes known as ‘roughage’) refers to the parts of plant-based foods that your body can’t fully digest. It’s found in the cell walls of plants. Foods from animal products such as meat, fish, eggs and dairy contain no fibre at all. Fibre can be roughly divided into three different types:
When insoluble fibre passes through your bowel, it absorbs a lot of water and increases the bulk of any waste matter. It also makes the waste softer, increasing the speed and ease with which it passes through your bowel.
By promoting a healthy bowel, a fibre-rich diet reduces the risk of bowel problems, including constipation and diverticular disease (when the bowel wall becomes inflamed and damaged). A high fibre diet may also reduce the risk of bowel (colon) cancer.
Soluble fibre also helps to stabilise your blood sugar levels as it slows down the rate at which glucose is absorbed into your blood stream. Along with a balanced diet with low glycemic index (GI) foods which take longer to break down in the blood stream, this can help keep your energy levels consistent throughout the day, and prevent sharp swings in blood sugar levels that can adversely affect your health in the long run. Maintaining a healthy blood sugar level is particularly helpful if you have diabetes or pre-diabetes.
Soluble fibre also helps to lower your blood cholesterol levels, which in turn reduces your risk of heart disease.
Fibre also makes you feel full which can help with appetite control if you’re trying to lose excess weight. Resistant starch is believed to provide food for ‘friendly’ microbes in your intestine. The friendly microbes produce a substance called butyrate which improves the acid balance of the colon. This helps the healthy microbes to grow while deterring unhealthy microbes from flourishing.
It’s best to increase your fibre intake gradually. A sudden increase may produce wind or flatulence, bloating and stomach cramps. It's also a good idea to drink plenty of fluids so the fibre has something to absorb, otherwise you may become constipated.
Dietitians’ Association of Australia (DAA) http://www.daa.asn.au
Better Health Channel. Fibre in food. [online] Melbourne, VIC: State Government of Victoria. c1999-2010 [updated May 2010, accessed 4 Aug 2010] Available from: http://www.betterhealth.vic.gov.au/bhcv2/bhcarticles.nsf/pages/fibre_in_food
Cancer Council. Position statement: Fibre, wholegrain cereals and cancer prevention. [online] Kings Cross, NSW; Cancer Council. Nov 2008 [accessed 4 Aug 2010] Available from: http://www.cancercouncil.com.au/
National Health & Medical Research Council. Nutrient Reference Values - Dietary Fibre. [online] Canberra, ACT: Commonwealth of Australia. c2009 [accessed 4 Aug 2010] Available from: http://www.nrv.gov.au/nutrients/dietary%20fibre.htmTop of page
This information has been developed and reviewed for Bupa by health professionals. To the best of their knowledge it is current and based on reputable sources of medical research. It should be used as a guide only and should not be relied upon as a substitute for professional medical or other health professional advice.
Bupa Australia Pty Ltd makes no warranties or representations regarding the completeness or accuracy of the information. Bupa Australia is not liable for any loss or damage you suffer arising out of the use of or reliance on the information. Except that which cannot be excluded by law. We recommend that you consult your doctor or other qualified health professional if you have questions or concerns about your health. For more details on how we produce our health content, visit the About our health information page.
Last published 31 October 2010