Gan Pou Wee
M.Pharm, MBBS, BCPS, R.Ph
Of late, gluten-free diet appears to be the new health trend among the health conscious. This is spurred by many of its purported health claims ranging from reducing cholesterol to alleviating symptoms of autism. How much of this is the truth, and how much is just a fad?
The bounce in dough: Gluten
Gluten is mainly found in wheat grains, rye, and barley as a storage protein. Collectively termed as gluten, it consists of hundreds of different proteins, but is mainly made up of gliadin and glutenin. Gluten is the reason why dough will stick, it is also responsible for many properties of dough such as its texture, bounce, and flavor.
Less obvious sources
Apart from wheat grains, rye, and barley, and products derived from them, there are “hidden” sources of gluten less widely known such as reconstituted seafood, processed meat, and vegetarian meat substitutes as well as butter, ice cream, seasonings, stuffings, dressings and marinades.
When gluten-free is NOT JUST A FAD
There is a spectrum of gluten-related disorders treated with a gluten-free diet. However, not all disorders are directly related to gluten. Below are a few examples of gluten-related disorders:
- Celiac disease is caused by the small intestine being overly-sensitive to gluten which becomes inflamed upon exposure. This disease is heavily influenced by genetics and people with this disease usually will experience diarrhea with foul-smelling, bulky and floating stools after taking gluten-containing food. They may also feel bloated, experience stomachache and weight loss due to poor absorption of nutrients.
- Wheat allergy is just like any other allergies but only specific to wheat. Usually the patients are allergic to gliadins, which as mentioned above, are a component of gluten. Therefore, taking food with gluten will cause an individual to develop itch, rashes, of even anaphylaxis (life-threatening allergic reaction where the person is unable to breathe and experiences severe drop in blood pressure).
- Non-coeliac gluten sensitivity. These patients experience stomach or abdominal symptoms similar to celiac disease but are tested negative for celiac and wheat allergy, although their condition improves when put on a gluten-free diet. This disease is still poorly understood and diagnosing them is not easy.
What gluten-free diet DOES NOT DO
There are numerous purported health benefits associated with the gluten-free diet which are not backed by medical evidence while some are even outright refuted by scientific studies.
- Weight Loss. There are no published scientific reports pertaining to gluten-free diet resulting in weight loss in people without celiac disease. Conversely, there are multiple reports which revealed that patients with celiac disease actually gained weight after being put on gluten-free diet.
- Reduction of heart disease. Again, there is no scientific data supporting this. In fact, a study published this year showed that gluten-free diet caused an increase in risk of heart diseases in patients without celiac disease.
- Boost immune system. Although there is no evidence to disprove of this, likewise there isn’t any evidence supporting this, rendering it just another baseless claim.
The grey area
They are several conditions that seem to improve with a gluten-free diet. These are backed by some scientific evidence although more convincing research is needed to support these observations. Similarly, there are also certain conditions that are said to be induced by gluten-free diet that require more sound research for verification.
- Autism: There are studies both supporting and refuting the claim that autism improves with gluten-free diet. The current evidence is at best only suggestive of a subgroup of patients with autism that may respond to gluten-free diet.
- Irritable bowel syndrome (IBS): IBS is a disease where a person suffers from constipation or diarrhea or both with no apparent cause. There is research that suggests that a gluten-free diet may help. There seems to be an overlap between IBS and coeliac disease or non-coeliac gluten sensitivity which may be the reason why certain patients with IBS may respond well to gluten-free diet.
- Diabetes: There is recent evidence presented in a scientific conference (unpublished data) suggesting that gluten-free diet induces diabetes.
- Toxicity: There is a recent study that suggests that individuals on a gluten-free diet are exposed to higher levels of arsenic and mercury.
Points to ponder upon
The gluten-free diet appears to be no different from a regular diet apart from the absence of gluten in food. It is important to note that many gluten-containing foods such as flour have been fortified with vitamins and generally contain a good amount of fiber which also acts as prebiotics. This promotes healthy gut by allowing beneficial intestinal bacterial to grow. Moreover, most processed products that are gluten-free actually contain high amounts of carbohydrate substitutes which are not so healthy.
Therefore, in the absence of an absolute need to go on a gluten-free diet, it is still not recommended until the pros and cons have been better weighed with more concrete evidence.
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