Will Going Gluten Free Cause Weight Loss?
We all know someone who "lost weight when they went gluten free", so you should probably try it too, right? Not so fast. In order to understand this complex topic, we should first understand some gluten basics. First of all, what is gluten? Is it a carbohydrate?
Nope! Gluten is actually protein that is found in certain carbohydrate sources, such as wheat, barley and rye. Gluten may also be found in many foods that you may not think of (it's often found in gravies, deli meats, cream sauces, you name it). This is because gluten has an important role in food chemistry - it is responsible for the elasticity of dough. Remember this, because we will get back to this fact later. But first...
Will You Benefit From Going Gluten Free?
The answer is not so clear. It used to be thought that someone should only go gluten free if they have Celiac Disease (also known as nontropical sprue), but now we know there are other individuals who may benefit from eliminating gluten from their diet. For example, non-celiac wheat sensitivity has now been demonstrated as a sensitivity associated with gluten or possibly another compound found in wheat. Since avoiding gluten inherently means avoiding wheat, this is likely to be an effective diet for these individuals. Also, some people may eliminate gluten as part of the Low FODMAP diet (mostly - there are some exceptions), a widely accepted diet used for the symptom management of irritable bowel syndrome (IBS). However, if you do not have a gluten sensitivity or a condition that requires you to avoid gluten, you may want to think twice before eliminating gluten from your diet. A large, recent study(1) revealed individuals without celiac disease who followed a gluten free diet may be at an increased risk for developing heart disease. The researchers concluded that this was likely due to these individuals eating too few whole grains while following a gluten free diet. Whole grains are important for a lot of reasons, one of which is fiber. (Note: it is certainly possible to get enough fiber on a gluten free diet - but it is best to work with a registered dietitian to learn about gluten free sources of fiber).
Not to mention, an unnecessarily restrictive diet poses the risk of nutrient deficiencies. Also, self diagnosing and eliminating certain foods without having the proper evaluation of a physician can cause symptom improvement that may be masking a more serious condition. If you believe you may be sensitive to gluten, it's best to meet with a gastroenterologist and develop an appropriate plan with your doctor and healthcare team.
So Why May People Lose Weight When They Avoid Gluten?
It is most likely that many people avoiding gluten are losing weight because they are consuming less processed food than they were before they cut out gluten and instead, opting for more whole foods. Fruits and vegetables are naturally gluten free, as are nuts and seeds, legumes and animal-based protein sources, such as eggs, fish, poultry and meat. So if someone were to cut out foods like excessive bagels, breads, pasta, pizza, doughnuts and other calorie-laden foods that happen to contain gluten, and consume more of these naturally gluten free whole foods, they will likely lose weight. However, this does not mean that one's diet needs to be completely devoid of these other foods in order to lose weight. The most sustainable approach to weight loss is diet that contains a variety of foods.
It is possible that decreasing one's carbohydrate intake may result in weight loss. Now, before you start that low-carb diet, let's get sidetracked for a minute - while some research demonstrates a low carbohydrate diet may result in weight loss, this method of weight loss is:
a) unlikely to be sustainable long-term (i.e. you may gain the weight back, because most people are unlikely to eat so few carbs for the rest of their lives)
and
b) some of the weight lost is likely to be water weight, especially at the beginning of a low carb (or lower carb) plan. This is because we store glucose (the simple sugar into which carbohydrates are broken down) in the form of glycogen, which also holds water. So remember that the next time you eliminate carbs for a week and drop a few pounds - it's not necessarily promoting changes in body composition (i.e. altering proportions of fat and muscle within your body).
But we digress. The confusing thing about going "gluten free" is it is acceptable on a gluten free diet to eat processed foods that are certified gluten free. This is great for someone who needs to avoid gluten due to medical reasons - it means they have food options just like everyone else. But, remember the role of gluten in food chemistry - it is responsible for the elasticity of dough. So basically, when gluten is removed from a food that typically contains gluten, that food is likely to taste like the cardboard package it comes in. That is why fat or sugar (or both) are typically added to "gluten free" packaged foods, such as cookies, cakes and bars - these ingredients will soften the food.
Bottom line? If you are going gluten free and focusing on more whole foods such as fruits, vegetables, nuts, seeds, legumes, eggs, lean meat, poultry and fish - that is a personal preference and should be perfectly fine. Just please make sure to consume a varied diet and ensure an adequate amount of carbohydrates (and fiber), such as brown rice, quinoa, legumes and starchy vegetables - to name a few. Also, be in tune with your body and decide whether it is necessary to restrict certain foods and assess how this is of benefit to you. Alternatively, if you are replacing your bagels with gluten free bagels as a means of losing weight, don't expect those pounds to drop so soon. Gluten itself is not likely to be hindering weight loss goals. In fact, there are many foods that do contain gluten that are recommended as a part of an overall healthy, balanced diet, as long as these foods are tolerated. And many of these foods contain fiber and protein to boot - which IS associated with weight loss.
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:j1892. doi: 10.1136/bmj.j1892.