As a dietitian, I get asked all the time, “Where do you stand on gluten-free diets?” I take issue with blaming gluten for what ails us. I take issue with saying gluten-free diets aren’t helpful for anyone who doesn’t have celiac disease.
But most of all, I take issue with all the hype and misinformation out there.
A recently published Harvard study drew some pretty dramatic headlines. It seems that going gluten-free could increase your risk for coronary heart disease, clearly the opposite effect that health seekers are hoping for.
But as with many nutrition studies, the results weren’t quite as groundbreaking as the headlines implied. For example: “If You Want to Avoid Heart Disease, Don’t Even Think of Going Gluten-Free” and “Gluten-free diet should not be eaten by people who are not coeliac, say scientists.”
If you take a look at the study, what the researchers actually say is that a gluten-free diet for people who don’t have celiac disease “should not be encouraged.” That’s quite different from saying it shouldn’t be followed at all. Avoiding gluten isn’t necessarily a health choice; it all depends on what you substitute it with. But gluten-free diets could help a small group of people who don’t have celiac disease, and we need to be open-minded to that.
After examining the study results, we can’t say much about the link between gluten and heart disease risk. This research looked at self-reported data from food frequency questionnaires for more than 100,000 men and women from the Health Professionals Follow-Up Study and the Nurses’ Health Study collected every four years over an average of 26 years. When the researchers looked at the link between estimated gluten intake and whether the person had a heart attack during the study period, the effect of gluten wasn’t significant.
The researchers then controlled for heart disease risk factors using statistical models. If someone was a smoker or overweight, for example, they controlled for that, cancelling out the effect that factor would have on heart disease risk to isolate the effect of gluten. Then the researchers tried controlling for refined grain intake, meaning they were really looking at the link between whole-grain gluten intake and heart disease risk. Only then did they find a statistically significant trend between higher (whole-grain) gluten intake and lower risk of heart disease.
We know that whole grains are helpful for lowering heart disease risk. We also know that less than 8 per cent of the population is getting the recommended amount of whole grains per day, so removing the effect of the main sources of gluten-containing foods (refined grains) from the statistical model is misleading. Claiming that gluten intake overall is heart-healthy is misrepresenting these findings.
Eating more whole grains instead of refined grains is a good move for your heart, and whether they contain gluten or not is up to you. I’d also argue that now that gluten-free whole grains such as millet, quinoa and buckwheat are more readily available, saying that gluten-free diets are low in whole grains is no longer a fair assumption.
Gluten sensitivity: On the rise or a common misdiagnosis?
Do you know people who swear they feel better after cutting gluten out of their diets? Nearly 30 per cent of US adults reported trying to cut back or avoid gluten in 2013; celiac disease was only diagnosed in 0.7 per cent of Americans in 2012.
So who makes up this large group of people who are going gluten-free but don’t have celiac disease? Some individuals turn to a gluten-free lifestyle to lose weight or because of the perception that it’s a healthier way to eat. But there is an ever-growing group of people who seem to have what’s been termed “gluten sensitivity”, and the scientific community is divided over how to define, diagnose and treat it.
Symptoms of non-celiac gluten sensitivity can include digestive symptoms such as pain and bloating in the abdomen, diarrhoea or constipation, or more generalised symptoms such as headaches, fatigue, brain fog, depression, joint pain and skin rashes. But because there is no biomarker that can identify gluten sensitivity, it’s difficult to diagnose. Research papers estimate the prevalence is anywhere from 0.5 to 6 per cent thanks to the wide variation in how it’s defined and the heterogeneity in study designs.
One way people can determine whether they are gluten-sensitive is by doing an elimination diet. Essentially, under the advice and supervision of a dietitian or doctor, the person with suspected gluten sensitivity removes foods from their diet and then slowly reintroduces them, taking detailed notes about their symptoms. Elimination diets take patience and diligence, which explains why some people may skip this step altogether. In my experience, some health practitioners will go straight to recommending a gluten-free diet, hoping it will clear up any digestive trouble or general malaise.
The reality is that most people who are following a gluten-free diet label themselves as gluten-sensitive rather than seeing a health professional and aren’t getting to the root of their food intolerances. As a dietitian, that worries me.
Feeling unwell after eating foods that contain gluten could be a wheat allergy, irritable bowel syndrome (IBS) or another food sensitivity, which may mean there are other components in food that the person’s body is reacting negatively to. For example, there seems to be significant overlap between gluten sensitivity and IBS, which may be helped by following the FODMAP diet.
FODMAPs are fermentable sugar alcohols and sugars including lactose (the sugar in milk) and fructose (the sugar in fruit). People might be avoiding gluten, a protein, without exploring the effect of FODMAPs and getting other IBS-specific recommendations under the care of a dietitian.
A survey completed by 147 adults who self-identified as having gluten sensitivity found that 25 per cent of respondents weren’t able to control their symptoms despite avoiding gluten, suggesting there are other causes that are unidentified and as such, going unaddressed.
There is also some pushback about whether gluten sensitivity is psychosomatic. A crossover study in which gluten-sensitive participants were given high-gluten, low-gluten and no-gluten (placebo) diets with or without other food components linked to digestive upset (FODMAPs) found that people had similar symptoms even on the gluten-free diet. Participants seemed to feel better when they were on low-FODMAP diets, which shows that gluten is being blamed, whether it deserves to be or not.
One of the most troubling effects of the gluten-free diet craze is that it could mean more people with celiac disease are going undiagnosed. The survey in adults who claimed to have gluten sensitivity found that 72 per cent were never tested for celiac disease. By not ruling out this serious illness, people with undiagnosed celiac disease could be exposing themselves to trace amounts of gluten that would be harmful to their health. In addition, many people aren’t aware that following a gluten-free diet before being tested for celiac disease can result in false negatives.
Are gluten-free diets healthy for those who don’t have celiac disease?
Anecdotally, I have clients who report feeling better when they’re avoiding gluten. Whether that’s because they’re replacing gluten-containing foods with more vegetables and gluten-free whole grains, are better able to digest other foods, or have a gluten-sensitivity, I don’t know. I do believe that each person’s ideal way of eating is different. Some of my clients feel great on gluten-free diets that emphasise animal protein, healthy fats and vegetables, while others eat more plant-based diets that include whole grains and beans. Nutrigenomics, the science of the interaction between our genes and nutrition, is an emerging field that may soon provide more answers.
Although some people feel more energised and improved digestion after avoiding gluten, positive results can’t be guaranteed. One of the main culprits for weight gain and fatigue is a diet high in refined grains and junk food that is high in calories but low in nutrients.
If you don’t have celiac disease but decide to swap out gluten-filled junk food for gluten-free junk food, I wouldn’t expect any major changes. However, a lot of people start to see results when they cut out gluten-filled junk food and eat more vegetables and gluten-free whole grains. If gluten is your gateway into unhealthy foods, then cutting it out might improve your overall diet quality. The key is eating a varied, nutrient-rich diet — whether it’s gluten-free or not.
Christy Brissette is a dietitian, foodie and president of 80TwentyNutrition.com