Should We Still Be Eating Wheat

By Helen Tran, APD

Wheat has featured in the human diet for more than 8,500 years, but more recently the media has led us to question if wheat is good for our health. A recent example of this manipulation of consumer perception is the documentary ‘What’s with Wheat?’ hosted by Australian Nutritionist, Cyndi O’Meara.

But it’s true that wheat isn’t tolerated by a small subset of the population, including those with diagnosed coeliac disease, a wheat allergy or non-coeliac wheat sensitivity, so we’ve taken a look at what the science says for the rest of us.

Does wheat cause a rise in coeliac disease and wheat sensitivity?

It’s suggested that modern wheat varieties created by genetic research, has led to the addition of a ‘new’ protein in wheat called gliadin, which in turn has led to an increase in the number of people with Coeliac disease and wheat sensitivity. But this notion is flawed. All varieties of wheat contain gliadin, including ancient and modern varieties, suggesting that we have always been exposed to gliadin in our diets.^(1,2)

Similarly, results from a study examining data from the 20^th and 21^st centuries in the United States do not support the theory that wheat breeding has caused a rise in gluten content in wheat.⁽³⁾ Another theory is that fructan in wheat has increased, but once again there is no well-designed research to support this. In one study, some ancient wheat species had a higher fructan content than modern wheat species.⁽⁴⁾

Overall, the evidence does not support the notion that modern wheat has a higher gliadin, gluten or fructan content compared to ancient varieties. It may be likely that the rise in coeliac disease and wheat sensitivity in the last 50 years comes from improvements in detection methods and an overwhelming increase in our awareness of how specific foods make us feel.

Does eating wheat lead to obesity and type 2 diabetes?

The relatively recent abundance of wheat products on our supermarket shelves has been identified as one factor responsible for the global increase in incidences of obesity and overweight. Whilst it’s tempting to find a single culprit for this very concerning trend, it is an oversimplification. This assertion overlooks the multiple interacting factors that can contribute to weight gain, including genetics, individual psychology, environment, dietary intake and level of physical activity.^(1,5)

Contrary to this claim, a recent analysis of the Australian National Nutrition Survey found that people who eat the recommended amount of core grain food each day are no more likely to be overweight than those who limit grain foods. Research also shows those people who eat whole grains, including whole grain wheat, have been shown to have the least amount of abdominal fat accumulation compared to those people who eat refined grains or limit all grains.⁽⁶⁾ In fact, eating foods made with whole grain wheat may have positive effects on long term weight management.⁽¹⁾

Currently, there is no clear evidence that wheat (whole grain or refined) is associated with an increased risk of type 2 diabetes. In fact, well-designed studies show that individuals who regularly eat whole grains (most of which are wheat based) are at a reduced risk of developing type 2 diabetes, compared to those who eat the least.^(1,8,9)

The protective effects of whole grain wheat comes from the dietary fibre, vitamins, minerals and phytochemicals it contains. So to reduce our risk of type 2 diabetes, the answer doesn’t lie in cutting out wheat completely, but in choosing whole grain and high fibre wheat foods instead with an aim to increase our intake of whole grains, including whole grain wheat.

Does eating wheat cause inflammation?

It’s been proposed that plant defense proteins called amylase trypsin inhibitors may cause chronic inflammation and activate the immune system^(10-12) but there is currently no evidence which supports this theory.

There is however, mounting evidence to suggest that higher intakes of whole grains may be protective against cardiovascular disease, hypertension, metabolic disorders and specific cancers. ^(13,14) Prebiotic fibres in fibre-rich grains stimulate the production of short chain fatty acids, such as butyrate, that have been shown to enhance the intestinal barrier function.⁽¹⁵⁾

This limited research shows that further research is needed before definitive conclusions can be drawn about the effects of wheat on inflammation.

Does eating wheat change the behaviour of children with Autism Spectrum Disorders?

More and more parents of children with Autism Spectrum Disorders (ASD) are adopting a gluten free diet to manage their child’s behaviour.⁽¹⁶⁾ It’s been hypothesised that children with ASD may have a leaky gut and peptides of gluten in gluten-containing foods could enter the central nervous system. The theory suggests that gluten peptides may intensify brain opioid activity and disrupt normal brain function.⁽¹⁶⁾ Scientific evidence for the leaky gut theory remains inconclusive and evidence to either support or refute the use of a gluten free diet for managing ASD is inadequate.

In the absence of evidence of an effect of gluten on ASD, it is not recommended that children are placed on a gluten-free diet as this diet has been shown to be deficient in nutrients that are important for a child’s growth and development, including B vitamins, iron, zinc and magnesium.

Instead it’s recommended that time and resources would be best spent on more robustly designed interventions.⁽¹⁷⁾ Until more evidence is available, a gluten free diet should only be adopted by children with coeliac disease or wheat sensitivity.

So what’s the bottom line?

Given the evidence, there appears to be no benefit in removing wheat from the diets of the general population. In fact, eating whole grain foods, predominately those that are wheat-based, have been shown to reduce chronic disease risk and are a leading source of essential nutrients in the Australian diet including fibre, B vitamins, iron, magnesium and iodine. Although more research is required to identify the specific link between wheat (whole grain and refined) and health outcomes, it appears that wheat may not negatively affect our health like the many claims that appear consistently in the media.

As such, it’s important not to rely solely on claims appearing in the media but consider the positives and negatives of all available evidence. After all, it’s up to us to make the best decision for our health.

For more information on the multiple benefits of wheat and whole grains, download the GLNC Grains for Health Report here or visit our website for recipes, factsheets and more here.

References

1.    Brouns FJPH, van Buul VJ, Shewry PR. Does wheat make us fat and sick? Journal of Cereal Science. 2013;58(2):209-15.

2.    Prandi B, Tedeschi T, Folloni S, Galaverna G, Sforza S. Peptides from gluten digestion: A comparison between old and modern wheat varieties. Food Research International.

3.    Kasarda DD. Can an increase in celiac disease be attributed to an increase in the gluten content of wheat as a consequence of wheat breeding? Journal of agricultural and food chemistry. 2013;61(6):1155-9.

4.    Ziegler JU, Steiner D, Longin CFH, Würschum T, Schweiggert RM, Carle R. Wheat and the irritable bowel syndrome – FODMAP levels of modern and ancient species and their retention during bread making. Journal of Functional Foods. 2016;25:257-66.

5.    Newell B, Proust K, Dyball R, McManus P. Seeing obesity as a systems problem. New South Wales Public Health Bulletin. 2007;18(12):214-8.

6.    Molenaar EA, Massaro JM, Jacques PF, Pou KM, Ellison RC, Hoffmann U, et al. Association of lifestyle factors with abdominal subcutaneous and visceral adiposity: the Framingham Heart Study. Diabetes care. 2009;32(3):505-10.

7.    Aune D, Norat T, Romundstad P, Vatten LJ. Whole grain and refined grain consumption and the risk of type 2 diabetes: a systematic review and dose–response meta-analysis of cohort studies. European Journal of Epidemiology. 2013;28(11):845-58.

8.    Wu H, Flint AJ, Qi Q, van Dam RM, Sampson LA, Rimm EB, et al. Association Between Dietary Whole Grain Intake and Risk of Mortality: Two Large Prospective Studies in US Men and Women. JAMA Intern Med. 2015.

9.    Kucek LK, Veenstra LD, Amnuaycheewa P, Sorrells ME. A Grounded Guide to Gluten: How Modern Genotypes and Processing Impact Wheat Sensitivity. Comprehensive Reviews in Food Science and Food Safety. 2015;14(3):285-302.

10. Cuccioloni M, Mozzicafreddo M, Ali I, Bonfili L, Cecarini V, Eleuteri AM, et al. Interaction between wheat alpha-amylase/trypsin bi-functional inhibitor and mammalian digestive enzymes: Kinetic, equilibrium and structural characterization of binding. Food chemistry. 2016;213:571-8.

11. Junker Y, Zeissig S, Kim S-J, Barisani D, Wieser H, Leffler DA, et al. Wheat amylase trypsin inhibitors drive intestinal inflammation via activation of toll-like receptor 4. The Journal of experimental medicine. 2012;209(13):2395-408.

12. Jones JM, Peña RJ, Korczak R, Braun HJ. CIMMYT Series on Carbohydrates, Wheat, Grains, and Health: Carbohydrates, Grains, and Wheat in Nutrition and Health: Their Relation to Digestion, Digestive Disorders, Blood Glucose, and Inflammation. Cereal Foods World. 2016;61(1):4-17.

13. Aune D, Keum N, Giovannucci E, Fadnes LT, Boffetta P, Greenwood DC, 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;353.

14. Brahe LK, Astrup A, Larsen LH. Is butyrate the link between diet, intestinal microbiota and obesity-related metabolic diseases? Obesity Reviews. 2013;14(12):950-9.

15. Christison GW, Ivany K. Elimination diets in autism spectrum disorders: any wheat amidst the chaff? Journal of developmental and behavioral pediatrics : JDBP. 2006;27(2 Suppl):S162-S71.

16. Hurwitz S. The Gluten-Free, Casein-Free Diet and Autism: Limited Return on Family Investment. Journal of Early Intervention. 2013;35(1):3-19.