Summary
A good article asking if Gluten is really the culprit for celiac.
http://www.newyorker.com/magazine/2014/11/03/grain
****
Gluten anxiety has been building for years, but it didn’t become acute until 2011, when a group led by Peter Gibson, a professor of gastroenterology at Monash University and the director of the G.I. unit at the Alfred Hospital, in Melbourne, seemed to provide evidence that gluten was capable of causing illness even in people who did not have celiac disease. Gibson and his colleagues recruited thirty-four people with irritable-bowel syndrome, all of whom had complained of stomach ailments that largely disappeared when they stopped eating gluten. He put them all on a strictly monitored gluten-free diet, but, unbeknownst to the subjects, about half got muffins and bread with gluten. It was a double-blind study, so neither the doctors nor the patients knew which muffins and bread contained gluten. But most of those who ate the gluten reported that the pain returned; for most of the others it did not. The study was small but meticulous, and the results were compelling. Several similar studies are now under way, but dietary research is notoriously time-consuming and difficult.
Gibson published his findings in the American Journal of Gastroenterology, but, along with other experts, he urged restraint in interpreting data from such a small study. Nevertheless, millions of people with vague symptoms of gastric distress suddenly found something concrete for which to blame their troubles. The market boomed, but the essential mystery remained unsolved: Why was gluten suddenly so hazardous? Perhaps, researchers thought, farmers had increased the protein (and gluten) content of wheat so drastically that people could no longer digest it properly.
But there is more to wheat than gluten. Wheat also contains a combination of complex carbohydrates, and the Australian team wondered if these could be responsible for the problems. Gibson and his colleagues devised a different study: they recruited a group of thirty-seven volunteers who seemed unable to digest gluten properly. This time, the researchers attempted to rule out the carbohydrates and confirm gluten as the culprit. Gibson put all the volunteers on a diet that was gluten-free and also free of a group of carbohydrates that he and his colleagues called fodmaps, an acronym for a series of words that few people will ever remember: fermentable oligosaccharides, disaccharides, monosaccharides, and polyols. Not all carbohydrates are considered fodmaps, but many types of foods contain them, including foods that are high in fructose, like honey, apples, mangoes, and watermelon; dairy products, like milk and ice cream; and fructans, such as garlic and onions.
Most people have no trouble digesting fodmaps, but these carbohydrates are osmotic, which means that they pull water into the intestinal tract. That can cause abdominal pain, bloating, and diarrhea. When the carbohydrates enter the small intestine undigested, they move on to the colon, where bacteria begin to break them down. That process causes fermentation, and one product of fermentation is gas. In Gibson’s new study, when the subjects were placed on a diet free of both gluten and fodmaps, their gastrointestinal symptoms abated. After two weeks, all of the participants reported that they felt better. Some subjects were then secretly given food that contained gluten; the symptoms did not recur. The study provided evidence that the 2011 study was wrong—or, at least, incomplete. The cause of the symptoms seemed to be fodmaps, not gluten; no biological markers were found in the blood, feces, or urine to suggest that gluten caused any unusual metabolic response.
In fact, fodmaps seem more likely than gluten to cause widespread intestinal distress, since bacteria regularly ferment carbohydrates but ferment protein less frequently. Although a fodmap-free diet is complicated, it permits people to eliminate individual foods temporarily and then reintroduce them systematically to determine which, if any, are responsible for their stomach problems. fodmaps are not as trendy as gluten and not as easy to understand. But, biologically, their role makes more sense, Murray says.
“That first paper, in 2011, blew our minds,” Murray told me. “Essentially, it said that people are intolerant of gluten, and it was based on a well-designed, double-blind study. When people were challenged with gluten, by eating the muffins, they got sick. We just couldn’t figure it out. But then came the second study. By then, it was almost too late to put the genie back in the bottle. You have millions of people out there completely convinced that they feel better when they don’t eat gluten—and they don’t want to hear anything different.”
The fodmap research, while influential and highly regarded, involved fewer than a hundred people, not enough to account definitively for the number of people who have abandoned foods that contain gluten. Several groups are trying to repeat those results. But studies like that take time. At present, there are no blood tests, biopsies, genetic markers, or antibodies that can confirm a diagnosis of non-celiac gluten sensitivity. There have been a few studies suggesting that people without celiac disease have a reason to eliminate gluten from their diet. But most of the data are unclear or preliminary. Doctors rarely diagnose non-celiac gluten sensitivity, and many don’t believe that it exists. Few people seem to have been deterred by the lack of evidence. “Everyone is trying to figure out what is going on, but nobody in medicine, at least not in my field, thinks this adds up to anything like the number of people who say they feel better when they take gluten out of their diet,” Murray said. “It’s hard to put a number on these things, but I would have to say that at least seventy per cent of it is hype and desire. There is just nothing obviously related to gluten that is wrong with most of these people.’’
http://www.newyorker.com/magazine/2014/11/03/grain
A good article asking if Gluten is really the culprit for celiac.
http://www.newyorker.com/magazine/2014/11/03/grain
****
Gluten anxiety has been building for years, but it didn’t become acute until 2011, when a group led by Peter Gibson, a professor of gastroenterology at Monash University and the director of the G.I. unit at the Alfred Hospital, in Melbourne, seemed to provide evidence that gluten was capable of causing illness even in people who did not have celiac disease. Gibson and his colleagues recruited thirty-four people with irritable-bowel syndrome, all of whom had complained of stomach ailments that largely disappeared when they stopped eating gluten. He put them all on a strictly monitored gluten-free diet, but, unbeknownst to the subjects, about half got muffins and bread with gluten. It was a double-blind study, so neither the doctors nor the patients knew which muffins and bread contained gluten. But most of those who ate the gluten reported that the pain returned; for most of the others it did not. The study was small but meticulous, and the results were compelling. Several similar studies are now under way, but dietary research is notoriously time-consuming and difficult.
Gibson published his findings in the American Journal of Gastroenterology, but, along with other experts, he urged restraint in interpreting data from such a small study. Nevertheless, millions of people with vague symptoms of gastric distress suddenly found something concrete for which to blame their troubles. The market boomed, but the essential mystery remained unsolved: Why was gluten suddenly so hazardous? Perhaps, researchers thought, farmers had increased the protein (and gluten) content of wheat so drastically that people could no longer digest it properly.
But there is more to wheat than gluten. Wheat also contains a combination of complex carbohydrates, and the Australian team wondered if these could be responsible for the problems. Gibson and his colleagues devised a different study: they recruited a group of thirty-seven volunteers who seemed unable to digest gluten properly. This time, the researchers attempted to rule out the carbohydrates and confirm gluten as the culprit. Gibson put all the volunteers on a diet that was gluten-free and also free of a group of carbohydrates that he and his colleagues called fodmaps, an acronym for a series of words that few people will ever remember: fermentable oligosaccharides, disaccharides, monosaccharides, and polyols. Not all carbohydrates are considered fodmaps, but many types of foods contain them, including foods that are high in fructose, like honey, apples, mangoes, and watermelon; dairy products, like milk and ice cream; and fructans, such as garlic and onions.
Most people have no trouble digesting fodmaps, but these carbohydrates are osmotic, which means that they pull water into the intestinal tract. That can cause abdominal pain, bloating, and diarrhea. When the carbohydrates enter the small intestine undigested, they move on to the colon, where bacteria begin to break them down. That process causes fermentation, and one product of fermentation is gas. In Gibson’s new study, when the subjects were placed on a diet free of both gluten and fodmaps, their gastrointestinal symptoms abated. After two weeks, all of the participants reported that they felt better. Some subjects were then secretly given food that contained gluten; the symptoms did not recur. The study provided evidence that the 2011 study was wrong—or, at least, incomplete. The cause of the symptoms seemed to be fodmaps, not gluten; no biological markers were found in the blood, feces, or urine to suggest that gluten caused any unusual metabolic response.
In fact, fodmaps seem more likely than gluten to cause widespread intestinal distress, since bacteria regularly ferment carbohydrates but ferment protein less frequently. Although a fodmap-free diet is complicated, it permits people to eliminate individual foods temporarily and then reintroduce them systematically to determine which, if any, are responsible for their stomach problems. fodmaps are not as trendy as gluten and not as easy to understand. But, biologically, their role makes more sense, Murray says.
“That first paper, in 2011, blew our minds,” Murray told me. “Essentially, it said that people are intolerant of gluten, and it was based on a well-designed, double-blind study. When people were challenged with gluten, by eating the muffins, they got sick. We just couldn’t figure it out. But then came the second study. By then, it was almost too late to put the genie back in the bottle. You have millions of people out there completely convinced that they feel better when they don’t eat gluten—and they don’t want to hear anything different.”
The fodmap research, while influential and highly regarded, involved fewer than a hundred people, not enough to account definitively for the number of people who have abandoned foods that contain gluten. Several groups are trying to repeat those results. But studies like that take time. At present, there are no blood tests, biopsies, genetic markers, or antibodies that can confirm a diagnosis of non-celiac gluten sensitivity. There have been a few studies suggesting that people without celiac disease have a reason to eliminate gluten from their diet. But most of the data are unclear or preliminary. Doctors rarely diagnose non-celiac gluten sensitivity, and many don’t believe that it exists. Few people seem to have been deterred by the lack of evidence. “Everyone is trying to figure out what is going on, but nobody in medicine, at least not in my field, thinks this adds up to anything like the number of people who say they feel better when they take gluten out of their diet,” Murray said. “It’s hard to put a number on these things, but I would have to say that at least seventy per cent of it is hype and desire. There is just nothing obviously related to gluten that is wrong with most of these people.’’
http://www.newyorker.com/magazine/2014/11/03/grain
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