Gluten-free diet can be bad for you if you don’t need it
Many people choosing to go gluten-free are just wasting their money on expensive health foods and could actually be doing themselves damage, according to a new review.
The University of Newcastle paper published in the Australian Medical Journal today highlights a recent study from Spain that found only 16 per cent of people who self-reported gluten sensitivity actually showed the symptoms in a proper trial.
The sample did not include those diagnosed as having coeliac disease or a wheat allergy. It's estimated only one in 100 people have a confirmed coeliac disease.
Lead author Michael Potter said about seven per cent of Australians were avoiding gluten, including a big group which had gastro intestinal symptoms and blamed them on gluten.
"Five out of six wheat avoiders are probably not truly gluten sensitive," he said. "The symptoms are usually there for a reason, it's just that gluten is not necessarily the answer."
Potter said non-coeliac gluten sensitivity was a "real condition" that had only come to light in the last five years or so.
However, a gluten-free diet was right for coeliacs, but not necessarily benign for those who did it for no reason, he said. "It is costly, it's inconvenient and there are even signals in the literature that it may make you more prone to vitamin deficiencies."
The review also suggested a gluten-free diet could boost the risk of heart attack or stroke by raising blood pressure, cholesterol levels and body weight.
Potter's advice for people who thought gluten was affecting them was to get checked for coeliac disease first. "Self-diagnosis is a dangerous thing to do. Non-specific gastro intestinal symptoms can be due to a whole range of things and modern medicine is able to treat a lot of them. See your GP."
He agreed the findings were not good news for the booming gluten-free food industry. "It is big business, there is a lot of popular press touting a gluten-free diet to make you healthier and make you slimmer, but at the moment there just isn't the evidence for that."
Christchurch paediatrician, gastro-enterologist, and food allergist Rodney Ford has believed in gluten's non-coeliac impact for years. "There was a time when gluten sensitivity was rubbished by the medical community and they said it didn't exist at all."
He said it was interesting that 1 in a 100 Kiwis were now estimated to be affected by coeliac disease, when he was studying medicine the estimate was 1 in 2000.
Dr Ford said gluten sensitivity problems were often a slow-burning issue and not easy to pick up in a quick trial. "A lot of my clinic patients who have severe eczema when taken off gluten can take six months to clear of eczema. When you put them back on, it takes about six weeks to come back."
He was also more positive about the gluten-free diet when done properly. "It's a way to overhaul your diet. People feel a lot better. You are changing a lot of things, people eat a lot more healthily. They are eating veggies and fruit they didn't have before, and eating less cakes and biscuits. So it's a lifestyle change as well.
"Somebody who is eating well and reducing gluten intake, getting fresh fruits and vegetables and going on a mostly plant-based diet is going to be a lot better.
"If you swap a croissant for a gluten-free croissant and a bun for a gluten-free bun … you are likely to have a more detrimental diet. You can't blame the gluten-free movement on having a bad diet. Some people not gluten-free have terrible diets."
Written by Ewan Sargent. Republished with permission of Stuff.co.nz.