What is gluten?

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About this video

Gluten is a protein complex in wheat, barley and rye, and it is central to three health conditions: celiac disease, grain allergy, and the disputed 'gluten intolerance'. The video traces how a 2011 study sparked the gluten-free craze and how a 2013 follow-up by Dr. Peter Gibson found no effect of gluten once FODMAPs were removed. It closes by explaining why gluten-free diets can seem healthy for reasons unrelated to gluten.

You'll be able to

  • describe the two proteins that make up gluten and the grains that contain it
  • explain how celiac disease, grain allergy and gluten intolerance differ
  • explain why the 2013 Gibson study changed the conclusion about gluten

Key words

Gluten
The main protein composite found in wheat, barley and rye, made of gliadin and glutenin.
Celiac disease
An autoimmune condition in which the immune system attacks the small intestine in response to gluten.
FODMAPs
Fermentable, poorly absorbed, short-chain carbohydrates that can cause bowel symptoms.
Gluten intolerance
The idea that eating gluten causes bowel symptoms in people without celiac disease or grain allergy.
Confounding factor
A variable that can distort the result of a study if it is not controlled for.
Transcript

- Nowadays when you take a stroll down the aisle at your local grocery store you'll notice that a lot of foods are labeled as Gluten free. In fact, in 2014, the U.S. sales of Gluten free labeled products was estimated to be about 23 billion dollars. So what exactly is Gluten and why is everybody talking about it?

Well, from a biological standpoint Gluten is composed of two different proteins. There is gliadin which I'll represent as these blue circles. And there's glutenin which I'll represent as these red strings. These two together are going to form what's called gluten.

Now gluten is the main protein composite of a lot of the grains that you eat. This includes things Wheat, Barley, and Rye. And this is really important because these are found in a lot of the foods that people typically eat. For example, you may see it in Bread, Pasta, Salad Dressings, and even Sausages.

So this is just a handful of the many, many, many different types of foods that contains these grains. And by extension will contain the gluten. Now why is gluten important in healthcare? It's because there are three major conditions in which gluten can cause problems.

The first is known as Celiac Disease. Celiac Disease is an Autoimmune Disease in which the body's own Immune System attacks the Small Intestine. It isn't exactly a new condition because it was first described in the Late 1800s. And in addition to that, it's actually quite rare.

It affects about one for every 70 to 300 people depending on which country you live in. In the U.S. that's equivalent to about 2.1 million people. The second major condition is having an allergy to the grains that contain gluten. So much like how many people have allergies to things like peanuts or eggs a lot of people can have allergies to these grains.

However, this is even less common than Celiac Disease. So if Celiac Disease and Grain Allergies are relatively rare, why is everybody talking about gluten? The reason is because of the third condition known as Gluten Intolerance. The idea behind Gluten Intolerance is that if you eat something containing gluten you'll experience all sorts of different symptoms associated with your bowels.

This can include things like Diarrhea and Constipation and Cramping and Bloating as well. Now the whole phenomenon of Gluten Intolerance really began in 2011 when a paper was published in The American Journal of Gastroenterology. So right here I have the exact title of that paper which says, "Gluten causes gastrointestinal symptoms "in subjects without celiac disease."

Basically, this paper concluded and I quote, "gluten is indeed a trigger of gut symptoms and tiredness." Thus began the Gluten free sensation. But in 2013, Dr. Peter Gibson who is the author of this study did a follow-up study. Now this is actually a pretty long title so I'm just going to read it off first and then we're going to digest it piece by piece.

So it says, "No Effects of Gluten in Patients "With Self-Reported Non-Celiac Gluten Sensitivity "After Dietary Reduction of Fermentable, Poorly Absorbed, "Short-Chain Carbohydrates." So first we can focus on this part right over here this Fermentable, Poorly Absorbed, Short-Chain Carbohydrates.

We have another word for this and it's really just an acronym it's simply known as FODMAPS. The words in this acronym are actually different from the words here but it's the same thing. Now these FODMAPS are basically just carbohydrates that are known to cause a lot of the symptoms that I mentioned earlier.

The things like cramping, and diarrhea, and constipation. So this study basically considered the fact that maybe it's actually these FODMAPS instead of the gluten that's causing these symptoms. So they basically did mostly the same stuff as the earlier study except they removed these FODMAPS from the situation.

It was kind of a confounding factor and they wanted to eliminate that. Then what they did was they put people on first, gluten filled diets. So I'll just label that as positive (+) gluten. And then they changed their diets to gluten free diets. So I'll just label that as minus (-) gluten.

And they basically just wanted to look at the effects of this. So if the earlier hypothesis that gluten causes these symptoms is true then their symptoms should improve because you're putting them on a gluten free diet. However, they found that there were No Effects of Gluten.

So gluten actually didn't do anything. It wasn't responsible for causing all of those symptoms. Now what does this all mean for us? Well, if you have Celiac Disease or Grain Allergies you should absolutely avoid consuming anything that contains Gluten in it. However, these conditions are pretty rare and they don't affect that many people.

So for the rest of us, should we adopt this Gluten free diet? Well, it's true that these Gluten free diets do tend to be healthy. But that's not because they lack Gluten it's because by their very nature they're healthy. They don't contain all sorts of processed foods and carbohydrates.

So because of that and not because they lack Gluten they are pretty healthy for you. So the jury is still kind of out on whether or not we should adopt a Gluten free diet. But the current scientific literature probably wouldn't support a Gluten free diet.

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