Gluten free diets are being hailed for their role in weight loss, and much, much more... There was a lot of ground to cover in this month’s myth bust, so it will be coming to you in a two part instalment. Part 1 clears up some background information about what gluten is and why people might avoid it for medical reasons while Part 2 looks at those other reasons people are avoiding gluten, like for weight loss and general health - enjoy Part 2: Why else go Gluten free? Beyond the conditions discussed in Part 1 of this monthly myth bust, gluten has been branded as the cause of weight gain, general feelings of lethargy, poor health, and inflammation which underpins heart disease, diabetes, cancer, and arthritis, amongst other things. Consequently, the hyped reasoning to avoid gluten includes increased energy levels, aiding weight loss, and a general “healthy” or “lighter” option. With this impressive health resume, does a gluten free diet live up to the hype - Should we all be avoiding gluten? As we’ve seen so far the evidence for specifically avoiding gluten beyond Celia Disease is limited and yet ordering from the gluten free menu seems to be the new “I’ll just have a salad …” Weight loss is quiet possibly the biggest preoccupation of our modern western society and of course we would just love to find something to ‘blame’ for our population-wide weight worries (other than poor dietary choices, limited physical activity and generally being immersed in an obesogenic environment) – enter Gluten. We’ve tried blaming carbohydrates, we’ve tried blaming fat and we’ve tried blaming sugar, next on the chopping block is gluten. The underlying mechanism by which gluten is blamed for weight gain is inflammation, which is also said to be the reason it causes heart disease, diabetes etc. There is evidence to support the inflammatory effect of gluten in people with Celiac Disease, as is to be expected, and even a little for those with NCGS, despite no clinical markers currently being accepted. (1) But within the general population the evidence is (again) limited. The one and only study which seems to be quoted as the ultimate ‘evidence’ that gluten causes weight gain in subjects without Celiac Disease or NCGS, claims that removing gluten from the diet of mice reduced inflammation, insulin resistance and adiposity (fatness), compared with mice fed a high fat diet (61% of energy from fat), comprising 4.5% gluten, however this diet is hardly reflective of the typical Western human diet, or even the recommended diet (e.g The Australian Dietary Guidelines), so the beneficial effects of a gluten-free diet as claimed by this research, seems a bit of a stretch (but of course more research is warranted). (2) The benefits of a gluten free diet in the general population is further questionable given that another study on human subjects with hyperlipidaemia, reported that increasing wheat gluten on a weight maintenance diet reduced triglyceride levels by 13% independent of fibre content, suggesting that gluten may in fact have some benefit in improving lifestyle related conditions. (3) Of course, we could then consider the plethora of data to support the beneficial role of whole grains, including wheat and other grains containing gluten, in type 2 diabetes, heart disease, some forms of cancer and weight management. (4) The fact is there is insufficient data to support any of the widely made claims the gluten causes weight gain, hampers weight loss, or causes inflammation, diabetes or heart disease within the general population. So despite a few mice seemingly benefiting from removing gluten from the diet, do I think cutting gluten from your diet should be the first lifestyle modification made to aid weight loss or improve lifestyle related conditions? Umm, No… Ultimately if people have lost weight by ‘going gluten free’, more than likely they have just cut their carbs, which we know results in short term “weight loss” largely from water losses. We know that a low carb diet results in no greater weight loss after 6 months than other dieting methods (such as low fat, high protein etc) and is difficult for many to sustain long term. So if you are stocking the pantry with gluten free products simply to lose weight you are wasting your time, your money and could actually be risking your health. Negative Consequences of avoiding Gluten Resistant starches in grains like wheat (which we know contains gluten) creates healthy gut bacteria shown to reduce the risk of some cancers, inflammatory conditions, and cardiovascular disease. (3) Given the dependence on wheat in the western diet a significant portion of resistance starch comes from wheat consumption and as such following a gluten free diet unnecessarily could have adverse effects on gut health. Conversely positive changes in gut health as a consequent of including whole grains in the diet have been seen within as little as 3 weeks. (3) Conclusion Despite the hype around gluten there certainly is no reason for the general population (outside of having a gluten related disorder) to jump on board this movement. Cutting gluten from your diet to improve your overall health, prevent disease or aid weight loss is not substantiated by current research and in fact, gluten could in fact have some health benefits. Although the research to support this is far from definitive, the role of grains in good health is definitely well understood. Of course branching out from wheat, irrespective of gluten, adds nutritional variety to the diet and assists to increase crop biodiversity so by all means enjoy a variety of grains, gluten free or otherwise, within your diet too. Summary - Celiac’ s must adhere to an exclusively gluten free diet
- Our understanding of NCGS, and specifically the role of gluten in this condition, is very primitive - There is insufficient evidence to say that a gluten free diet has any positive effect on conditions such as MS, schizophrenia, dementia or autism - There is similarly little evidence to say that a gluten free diet causes any harm in these conditions - There is insufficient evidence to say a gluten free diet has an effect on weight loss, obesity, inflammation, insulin sensitivity or diabetes - The gluten free food industry is cashing in on processed products that are equally energy dense and nutrient deficient as their gluten containing counter parts - Whole grains are good for us and many of them just happen to be gluten free This is a really great fact sheet that guides you through the spectrum of gluten related disorders including symptoms and appropriate diagnostic protocol. (open fact sheet)
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August 2014
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