So what is gluten? And is there really any reason to avoid it?
Recently, gluten and gluten free diets have occupied a significant amount of media coverage, with conflicting messages spruiking gluten free diets as the answer to many health ailments including as an effective tool for weight loss and treatment for all sorts of digestive issues. Now the tide is shifting in favour of more positive coverage around gluten, but there are still many misconceptions surrounding gluten and gluten free diets. So we’ve answered a few of the most common questions on gluten which we hope will help to set the record straight…
But firstly, what is gluten and where is it found?
Gluten is a natural protein, found not only in wheat, but also rye, barley, oats and spelt. It has a vital functional role in baking as it gives the dough its elasticity, holding the dough together and preventing crumbling during rolling and shaping.
Gluten is found in many foods, including products made with gluten containing grains such as breads, breakfast cereals, crispbreads, pasta, as well as biscuits, cakes, pastry and pizza. But gluten is also found in unexpected foods, such as some processed meats, ready-to-eat soups, ice cream and sauces. So it pays to check the label if you need to avoid gluten!
Despite many foods on the market containing gluten, there are still plenty of good quality grain foods that are naturally gluten free including all varieties of rice, some rice noodles, millet, sorghum, teff and pseudo grains – quinoa, buckwheat, amaranth as well as gluten free varieties of foods like breads, breakfast cereals and crackers. So you can still enjoy the goodness of grains on a gluten free diet.
One common misconception is that a gluten free diet means cutting out all grains – but gluten free doesn’t mean grain free!
So what is coeliac disease?
Coeliac disease affects just a small percentage of people with approximately 1 in 70 Australians1 being diagnosed with the disease. It’s characterised by an abnormal immune reaction to gluten, which causes small bowel damage. The tiny, finger-like projections which line the bowel (villi) become inflamed and flattened, which leads to reduced nutrient absorption and gastrointestinal symptoms such as diarrhoea, bloating and abdominal pain. Other symptoms can include fatigue, vitamin and mineral deficiencies, skin rashes and joint pains. Currently, the only treatment for coeliac disease is a completely gluten free diet.
If you suspect you may have coeliac disease, always seek advice from a qualified medical practitioner before removing any foods from your diet.
What about gluten intolerance or non-coeliac gluten sensitivity?
With a growing number of the population suffering from coeliac like symptoms, recent evidence suggests that gluten intolerance or non-coeliac gluten sensitivity may exist. But there is so much that we still don’t know about this condition. And with the lack of a clear medical marker to confirm whether or not a person is gluten intolerant, this makes clinical diagnosis very difficult.
There is growing evidence to suggest that some people may suffer from a gluten intolerance – but currently there is no clear indicator to diagnose a sensitivity or intolerance.
Are gluten free foods healthier than foods containing gluten?
A gluten free diet is often promoted as a ‘healthier diet’ than one containing gluten, but research has demonstrated that gluten free foods in Australia are no healthier than the foods they are designed to replace2. What’s more gluten free diets have been shown to be higher in calories and fat (particularly saturated fat) and gluten free foods generally have a higher glycaemic index3, 4 than their gluten containing counterparts.
Additionally, following a gluten free diet can be very restrictive especially when eating out and can even be up to two to three times more expensive than that of a standard diet,5 as many gluten free staples cost significantly more than their regular alternatives6, 7.
Following a gluten free diet can cost up to two to three times more than a regular diet!
I’ve heard that eliminating gluten can help with weight loss – is this true?
Despite the frequent endorsement of a gluten free diet to help with weight loss, there’s actually no published evidence to show that gluten free diets directly result in weight loss in healthy people without coeliac disease or gluten intolerance17, 18.
However, some individuals who follow a gluten free diet may experience weight loss as they improve the overall nutritional quality of their diet by eating fewer processed, nutrient poor foods and eating more fruit, vegetables and legumes. So any weight loss experienced whilst following a gluten free diet could be due to reduced overall energy intake and better food choices, rather than the elimination of gluten19.
So are there any risks associated with eliminating gluten?
In short, there could be – a long term gluten free diet may actually increase your risk of falling short of nutritional requirements, particularly with relation to fibre3, 9-11. Micronutrient intakes have also been shown to be poor, particularly for vitamin D, vitamin B12 and folate intake, in addition to minerals such as iron, zinc, magnesium and calcium3.
Avoiding gluten containing foods are likely to have health implications in the long term given their important role in bowel health12, with some evidence suggesting that a gluten free diet may have a negative effect on the composition of the gut microbiome13, 14. Additionally large population studies have shown that gluten intake is not associated with coronary heart disease,15 and that low gluten diets may actually increase the risk of type 2 diabetes16. This is likely due to the fact that individuals who follow a gluten free diet also restrict good quality grain foods, particularly those that are rich in cereal fibre and whole grain – both of which have been shown to lower the risk of chronic diseases such as heart disease and type 2 diabetes.
Low gluten diets may actually increase your risk of type 2 diabetes.
So what are the benefits of consuming foods that contain gluten?
If you have no medical reason to avoid gluten, there are many health benefits associated with including gluten containing grain foods in your diet…
- Grain foods are the leading contributors of many key nutrients in the Australian diet, including fibre, folate, thiamin, iron, magnesium and iodine20.
- Additionally, eating at least three serves of whole grain per day has been shown to reduce the risk of incidence and death from heart disease, type 2 diabetes and some cancers21-24.
- Finally, increased intake of whole grains and dietary fibre is associated with less weight gain over time25-32.
Grain foods, particularly those that are high in fibre and whole grains, are highly nutritious and are associated with reduced risk of chronic disease!
So what’s the bottom line?
For those who don’t have diagnosed coeliac disease, there is no reason to follow a gluten free diet or even limit or avoid gluten containing foods. But it’s important to remember that you can still enjoy the benefits of gluten free grains even if you follow a gluten free diet – find out more here.
Remember, gluten free doesn’t mean grain free!
Want to find out more about current controversial topics? Click on the links to read our Hot Topics on Carbohydrates and Sugar in Grain Foods.
GLNC encourages anyone with a suspected coeliac disease or gluten intolerance to seek advice from a qualified medical practitioner. If coeliac disease is excluded, GLNC recommends individuals seek guidance from an Accredited Practising Dietitian to investigate other dietary triggers such as FODMAPs.
- Coeliac Disease. Coeliac Australia. Available at: http://www.coeliac.org.au/coeliac-disease/. Accessed 21 July, 2016.
- Wu JH, Neal B, Trevena H, et al. Are gluten-free foods healthier than non-gluten-free foods? An evaluation of supermarket products in Australia. Br J Nutr. Aug 14 2015;114(3):448-454.
- Vici G, Belli L, Biondi M, Polzonetti V. Gluten free diet and nutrient deficiencies: a review. Clinical Nutrition. 2016.
- Reilly NR. The Gluten-Free Diet: Recognizing Fact, Fiction, and Fad. The Journal of Pediatrics. 2016.
- Lee AR, Ng DL, Zivin J, Green PH. Economic burden of a gluten-free diet. J Hum Nutr Diet. Oct 2007;20(5):423-430.
- Lambert K, Ficken C. Cost and affordability of a nutritionally balanced gluten-free diet: Is following a gluten-free diet affordable? Nutrition & Dietetics. 2015:n/a-n/a.
- Estevez V, Ayala J, Vespa C, Araya M. The gluten-free basic food basket: a problem of availability, cost and nutritional composition. Eur J Clin Nutr. 10//print 2016;70(10):1215-1217.
- Bardella MT, Elli L, Ferretti F. Non Celiac Gluten Sensitivity. Current Gastroenterology Reports. 2016;18(12):63.
- Thompson T, Dennis M, Higgins LA, Lee AR, Sharrett MK. Gluten-free diet survey: are Americans with coeliac disease consuming recommended amounts of fibre, iron, calcium and grain foods? J Hum Nutr Diet. Jun 2005;18(3):163-169.
- Shewry PR, Hey SJ. Do we need to worry about eating wheat? Nutrition Bulletin. 2016;41(1):6-13.
- Shepherd SJ, Gibson PR. Nutritional inadequacies of the gluten-free diet in both recently-diagnosed and long-term patients with coeliac disease. Journal of Human Nutrition and Dietetics. 2013;26(4):349-358.
- Boyce PM, Koloski NA, Talley NJ. Irritable bowel syndrome according to varying diagnostic criteria: are the new Rome II criteria unnecessarily restrictive for research and practice? Am J Gastroenterol. Nov 2000;95(11):3176-3183.
- Bonder MJ, Tigchelaar EF, Cai X, et al. The influence of a short-term gluten-free diet on the human gut microbiome. Genome Medicine. 2016;8(1):1-11.
- Graf D, Di Cagno R, Fak F, et al. Contribution of diet to the composition of the human gut microbiota. Microb Ecol Health Dis. 2015;26:26164.
- Lebwohl B, Cao Y, Zong G, et al. Long term gluten consumption in adults without celiac disease and risk of coronary heart disease: prospective cohort study. BMJ. 2017;357.
- Zong G, Lebwohl B, Hu F, et al. Associations of Gluten Intake with Type 2 Diabetes Risk and Weight Gain in Three Large Prospective Cohort Studies of US Men and Women. Unpublished. 2017.
- Gaesser GA, Angadi SS. Gluten-free diet: imprudent dietary advice for the general population? J Acad Nutr Diet. Sep 2012;112(9):1330-1333.
- Gaesser GA, Angadi SS. Navigating the gluten-free boom. Journal of the American Academy of Physician Assistants. 2015;28(8):1-7.
- Staudacher HM, Gibson PR. How healthy is a gluten-free diet? British Journal of Nutrition. 2015/11/28 2015;114(10):1539-1541.
- ABS. Australian Health Survey: Nutrition First Results – Foods and Nutrients, 2011-12: Australian Bureau of Statistics; 2014.
- Aune D, Keum N, Giovannucci E, et al. Whole grain consumption and risk of cardiovascular disease, cancer, and all cause and cause specific mortality: systematic review and dose-response meta-analysis of prospective studies. BMJ. 2016-06-14 22:33:50 2016;353.
- McRae MP. Health Benefits of Dietary Whole Grains: An Umbrella Review of Meta-analyses. J Chiropr Med. Mar 2017;16(1):10-18.
- Chen G-C, Tong X, Xu J-Y, et al. Whole-grain intake and total, cardiovascular, and cancer mortality: a systematic review and meta-analysis of prospective studies. The American Journal of Clinical Nutrition. May 25, 2016 2016.
- Zong G, Gao A, Hu FB, Sun Q. Whole Grain Intake and Mortality From All Causes, Cardiovascular Disease, and Cancer: A Meta-Analysis of Prospective Cohort Studies. Circulation. June 14, 2016 2016;133(24):2370-2380.
- Williams PG, Grafenauer SJ, O’Shea JE. Cereal grains, legumes, and weight management: a comprehensive review of the scientific evidence. Nutr Rev. Apr 2008;66(4):171-182.
- Mozaffarian D, Hao T, Rimm EB, Willett WC, Hu FB. Changes in Diet and Lifestyle and Long-Term Weight Gain in Women and Men. New England Journal of Medicine. 2011;364(25):2392-2404.
- Du H, van der AD, Boshuizen HC, et al. Dietary fiber and subsequent changes in body weight and waist circumference in European men and women. Am J Clin Nutr. Feb 2010;91(2):329-336.
- Feskens EJ, Sluik D, Du H. The Association Between Diet and Obesity in Specific European Cohorts: DiOGenes and EPIC-PANACEA. Curr Obes Rep. Mar 2014;3(1):67-78.
- Koh-Banerjee P, Franz M, Sampson L, et al. Changes in whole-grain, bran, and cereal fiber consumption in relation to 8-y weight gain among men. The American Journal of Clinical Nutrition. November 1, 2004 2004;80(5):1237-1245.
- Liu S, Willett WC, Manson JE, Hu FB, Rosner B, Colditz G. Relation between changes in intakes of dietary fiber and grain products and changes in weight and development of obesity among middle-aged women. The American Journal of Clinical Nutrition. November 1, 2003 2003;78(5):920-927.
- Koh-Banerjee P, Rimm EB. Whole grain consumption and weight gain: a review of the epidemiological evidence, potential mechanisms and opportunities for future research. Proc Nutr Soc. Feb 2003;62(1):25-29.
- Ye EQ, Chacko SA, Chou EL, Kugizaki M, Liu S. Greater whole-grain intake is associated with lower risk of type 2 diabetes, cardiovascular disease, and weight gain. J Nutr. Jul 2012;142(7):1304-1313.