Does a gluten free diet help weight loss?
It's becoming increasingly popular to go gluten free to try lose a few kilos. But is it the gluten specifically or other factors causing any shift on the scales?
What is gluten?
Gluten is the collective term used to describe the storage proteins found in wheat, rye, barley and oats (gliadin, secalin, hordein and avenin respectively). It's also found in any of their derivatives such as spelt, triticale, kamut and any foods containing these grains such as bread, pasta, couscous, sauce mixes and soy sauce.
Does removing gluten cut calories?
Yes and no.
It totally depends on what you're cutting out or changing in your diet. Removing gluten itself is unlikely to be solely responsible for a reduced energy intake or weight loss. It's more likely due to changes, modifications or foods removed from the diet as a result of going gluten free. For example, say you stop eating a number of energy dense foods containing gluten like biscuits and cakes, and start eating more fruits and vegetables. You might see some weight shift due to the reduced fat, sugar and energy from those changes. However, if you replaced those biscuits & cakes with gluten-free versions then you'd be no better off as they usually contain just as much energy. Sometimes more.
It's quite common for people with coeliac disease to gain weight rather than lose it after first being diagnosed and starting a gluten free diet. This usually stabilises after a few kilograms and shows that the gut is healing and food is being absorbed properly.
Does gluten have an impact on metabolism?
There have been some studies showing an effect on metabolism in mouse-models, but current research isn't strong enough to suggest the same in humans. Most human research looking at metabolism or changes in BMI have been observational studies in people with coeliac disease. This type of research isn't able to determine a cause and effect response - where eating gluten caused x amount of weight change.
One study looking at BMI changes after diagnosis found that those who were underweight gained weight on a gluten-free diet, while those who were overweight or obese lost weight. There are lots of reason why this could occur. A diagnosis of coeliac disease combined with regular healthcare professional input might encourage those who are overweight or obese to improve their overall diet and lifestyle, resulting in some weight loss.
Who does a gluten free diet best suit?
The gluten free diet is first and foremost for people with coeliac disease. It's the only treatment (currently) and avoiding all traces of gluten is essential for long term health. Even eating crumbs of normal bread on a regular basis can cause ongoing damage. People with a wheat allergy or intolerance may also follow a gluten free diet.
People with non-coeliac gluten sensitivity can also benefit from a gluten-free diet. However, current knowledge in this area is limited and there are no biomarkers or clear diagnostic pathways. Current knowledge on non-coeliac gluten sensitivity has been compared to what we knew about coeliac disease around 40 years ago. So watch this space to see what new research brings.
Other people who may indirectly follow a gluten-free diet are those with irritable bowel syndrome on a low-FODMAP diet. Other nutritional components in wheat, barley and rye (apart from gluten) can initiate symptoms in some people with IBS so these grains are avoided during the elimination phase of the diet and my be reintroduced if tolerated.
If you don't have coeliac disease, is there any harm going gluten free?
If you have any concerns that gluten causes you issues then you should always get tested BEFORE going gluten free. You need to be eating gluten for the tests to work. If you stop eating gluten and feel better, it's much, much harder to reintroduce it for those tests.
Some studies have shown that a gluten free diet can be deficient in certain nutrients so it's important that it's balanced enough to meet your requirements. Typically people with coeliac disease will receive follow up with their healthcare practitioners, including blood tests looking for specific deficiencies. Fibre in particular can be lower in gluten-free foods so choose high fibre options to keep your bowels happy.
Gemma
Gemma Sampson RD APD
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