If you're seeing this message, it means we're having trouble loading external resources on our website.

If you're behind a web filter, please make sure that the domains *.kastatic.org and *.kasandbox.org are unblocked.

Main content
Current time:0:00Total duration:4:49

Video 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 and in fact in 2014 the US sales of gluten-free labelled 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 glidin which I'll represent as these blue circles and there is gluten in which I'll represent as these red strengths 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 like 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 health care 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 2000 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 kind of 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 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 consider 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 want 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 glue 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 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 hell but that's not because they like 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 like 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