OK, so I made up the quote above, but it captures a certain zeitgeist that’s in the air right now. The media is all too keen to uncritically give gluten-free and clean diets a kicking at the moment, wagging fingers at all those ‘silly people’ who fell for the anti-gluten message even though they don’t have coeliac disease – what fools!
Except, as we have explained in multiple articles on this site, gluten has a far greater reach than that 1% who have classic coeliac disease. Non coeliac gluten sensitivity (NCGS) is a recognised and studied condition, with an estimated prevalence of up to 6% of the population.
And even a cursory look behind these dismissive headlines shows that the studies they are based on add almost nothing to our understanding of gluten pathology, and indeed contradict themselves. Continue reading
▲ Image: Pawel Kuczynski
“Give us this day our daily bread (…) but deliver us from evil”
—Matthew 6:11, 13
This is an update on our previous series of articles “Why No One Should Eat Grains” which were published in 2015; we recommend you read them too if you want to get your brain around this topic (before gluten makes toast of it!):
- Part 1 – Coeliac Disease, The tip of the iceberg
- Part 2 – The definitive guide to Non Coeliac Gluten Sensitivity
- Part 3 – Ten more reasons to avoid wheat
- Introduction – “deliver us from evil”
- Gluten related disorders on the rise – but why?
- Amylase Trypsin Inhibitors – activate myeloid cells
- Type 1 diabetes – gluten affects the pancreas of even healthy mice
- Grain globulins – contain coeliac and T1 diabetes reactive proteins
- Oats – evidence that they should be avoided in coeliac disease
- IBS and gluten sensitivity – gluten is often the problem
- New coeliac auto-antibodies identified – linked to autoimmune polyneuropathies
- Neurological effects of gluten – Simiar in coeliac and NCGS
- Gluten in Latin America – high levels of self reported gluten avoidance.
Read time: 11 minutes (2200 words)
The Express (September 23rd) reports on a study that assigned 139 adults to one of three cheese regimens.
One group was given high-fat cheese daily, the second received a reduced-fat version, while the third group had jam and bread (!). The high fat cheese group saw a marked increase in their HDL cholesterol levels. Continue reading
- Gluten free diets benefit otherwise healthy people
- Pasture fed meat – Dexter cattle and Dartmoor ponies
- Ketogenic diet for better brain function, weight loss and endurance sports
- A plethora of Vitamin D studies
- ‘False alarm’ over red meat and cancer
- Chocolate prices to soar
New UK study vindicates gluten-free diets in otherwise healthy people
Just creeping into this month’s round up – The Daily Mail (30th November) reports on the ‘Going Gluten Free’ study organised by Aberdeen University’s Rowett Institute of Nutrition and Health.
It found that 3 weeks on a gluten free diet reduced bloating, flatulence and fatigue in otherwise healthy participants. Dr Alexandra Johnstone, of the Rowett Institute of Nutrition and Health, said: ‘It was interesting to discover that a gluten-free diet improves feelings of fatigue, with participants reporting much higher energy levels during the gluten-free period of the study.
‘The fact that they were able to start tasks quicker, concentrate better and think clearer during this time, and felt the need to rest less, all point towards the idea that sensitivity to gluten does exist for some individuals who don’t have coeliac disease.
Gluten free diets have been linked with poor dietary habits as individuals head for the gluten-free aisles, but recent promotion of real foods may have paid off: in this study participants overall dietary quality improved with consumption of more fruit and vegetables and an increased fibre consumption! I’ve highlighted that as we have been arguing on this blog that a proper gluten-free diet should improve the overall diet and lead to increased fibre intake.
Just a pity it was part-funded by a gluten-free food manufacturer.
Pasture-fed meat #1: Cattle help preserve rare South Downs grassland
The role of large herbivores in the landscape is increasingly being recognised for their environmental benefits. The meat from such animals is also considered healthier – higher in omega-3 fats, vitamin A and E. So it was pleasing to read in The West Sussex Gazette (31st October) of the recent introduction of Dexter cattle – a short stocky breed – to maintain endangered South Downs grassland at Steyning, West Sussex. What is more, the meat from these animals is available from Garlic Wood Farm butchers.
“My aim was to establish an efficient and sustainable farming system, producing a quality product raised solely on pasture that would benefit both the environment and human health.” – Frances Sedgwick, Cattle Breeder
Pasture-fed meat #2: Dartmoor Ponies
Also looking at the intersection of conservation and food was Radio 4’s Hardeep’s Sunday Lunch (29th November) which addressed a controversial topic: the proposal that we should encourage the use of Dartmoor hill ponies for meat.
Dartmoor and Exmoor have semi-wild pony populations that helped create those iconic landscapes, but economics mean that their numbers are dwindling. One proposal to keep this ancient form of land management viable is to encourage eating of pony meat. You can listen again until 28th December to this thoughtful and heart felt radio documentary.
Closer to home, the Knepp rewilding project also has herds of Exmoor ponies that look for all the world like the 17,000 year old cave paintings from Lascaux in France. Knepp too is facing the thorny question of whether it is right that these magnificent animals should go to waste when their population needs culling, rather than sold as prime pasture-fed meat. I’m sure the cave painters wouldn’t have any doubts.
Ketogenic diet: Caproic acid
New Scientist (25th November – you need to register to read it) has an article on the ketogenic diet for epilepsy, but also touches on its uses in other brain disorders and cancer. It’s worth a look as it provides a reasonable overview of some of the basics of the diet. However, the news bit is that researchers recently found (in rats at least) that the saturated fatty acid known as decanoic or caproic acid suppressed epileptic brain activity rather than the ketones.
Caproic acid is present in coconut oil (10%) and butter (2%), both of which can be used in the ketogenic diet. Unfortunately, neither the paper, nor New Scientist point out that in humans seizure control has be achieved without the use of this medium chain triglyceride, indicating that there is more to the ketogenic diet than caproic acid. Both ketones and low-glucose/insulin levels induced by the diet have been shown to have multiple protective effects on the brain.
Meanwhile the ketogenic diet for weight loss featured in The Express (23rd November) with typically tabloid panache: ‘Woman shed a THIRD of her bodyweight eating MORE bacon and butter’.
The ketogenic diet is increasingly being used in endurance sport as reported in Men’s Fitness (17th November), based on a study by world expert Jeff Volek, in which the fat burning levels of athletes on the ketogenic diet was found to be twice that of carb loading athletes.
It’s been a big month for vitamin D research with a host of stories making the newspapers:
- Vitamin D supplements increase exercise performance and reduce stress hormones The Mirror (1st November)
- Vitamin D levels need to be over 40 ng/dL to reduce osteoporosis EurekAlert! (2nd November)
- Differences in vitamin D status may account for disparities in breast cancer survival rates News Medical (5th November)
- Study identifies less than 15 ng/dL vitamin D levels increase heart risk Medical News Today (10th November)
- Low vitamin D levels linked to erectile dysfunction The Daily Mail (16th November)
- Low vitamin D may hamper HIV treatment in adults Medical News Today (18th November)
- Vitamin D supplements reduce asthma exacerbations but not the frequency or severity of their colds News Medical (30th November)
In previous posts we have advocated maximising vitamin D levels from midday sun exposure short of burning (Why April 15th is D-Day in the south of England) so as to gain the highest UVB:UVA ratio. So it is gratifying to see researchers from the University of Oslo come to the same conclusion in a paper published this month:
The best way to obtain a given dose of vitamin D with minimal carcinogenic risk is through a non-burning exposure in the middle of the day, rather than in the afternoon or morning. Grigalavicius et al, International journal of dermatology (Nov, 2015)
Here at Rosemary Cottage Clinic patients avail themselves of the wall mounted UVB 311nm narrowband light box on a weekly basis throughout the autumn and winter months to ensure they retain healthy levels of vitamin D to keep them well.
For those who wish to check their vitamin D levels I now have sealed test kits in stock at just £28 each, supplied by a specialist vitamin D test centre. So if you want to do a ‘before and after’ test get in contact to arrange it.
A false alarm on red meat and cancer
Following last month’s panic when the WHO classified red meat as a possible carcinogen the UK saw double digit falls in sales for three weeks. So it’s nice to see The Financial Times (24th November) taking a critical look at the quality of the data, like we did, and concluding that it was a ‘false alarm’.
Gordon Guyatt, an epidemiologist and professor of medicine at Hamilton’s McMaster University said “Two large trials have tested for evidence and the WHO ignored both of them.” He claims the WHO evidence is “very modest” and might easily be attributable to other confounding factors observational studies can’t fully adjust for (The National Post, 29th October).
It has also come to light that one of the leading advisors to the WHO is a lifelong vegetarian who has voiced moral and environmental objections to meat eating – how objective is that?
As if to make up for damage done, The Daily Mail (2nd November) had a pretty good article reviewing many of the health benefits associated with meat.
Chocolate prices to soar
Sorry to end on a bad note but forecasters are predicting chocolate prices will rise next year thanks to poor harvests in West Africa and strong winds caused by the El Nino weather system. If you can bear to read more, The Telegraph (30th November) give the full gory details.
In the past few years it has become apparent that “classic” coeliac disease represents the tip of the iceberg of an overall disease burden
In part 1 we looked at coeliac disease which affects 1% of the population worldwide, but forms only the tip of the gluten iceberg. In this post I will examine the research around the emerging clinical entity known as Non Coeliac Gluten Sensitivity which affects at least six times as many people.
- Non Coeliac Gluten Sensitivity (NCGS) shares certain features with coeliac disease (CD): symptoms are primarily gastrointestinal (GI), but commonly also systemic (mainly neurological), and symptoms improve or fully resolve on a gluten-free diet (GFD).
- However, unlike coeliac disease NCGS has no identified genetic risk factors (e.g. HLA-DQ2/8 which is associated with coeliac), and has no specific serum markers, making it a diagnosis of exclusion. Furthermore, NCGS is not an autoimmune disease and does not show small intestine atrophy.
- Defining and diagnosing NCGS is problematic, but the prevalence of NCGS appears to be six times higher than coeliac disease.
Early evidence for gluten sensitivity outside of coeliac disease
The first confirmation of gluten reactions in non-coeliacs goes back to a paper in Gastroenterology in 1980:
Eight adult female patients suffering from abdominal pain and chronic diarrhea which was often incapacitating and frequently nocturnal, had dramatic relief on a gluten-free diet and return of symptoms after gluten challenge.
These patients are typical of what is now called Non Coelaic Gluten Sensitivity (NCGS) – predominately female, IBS-like symptoms, improving on a gluten free diet (GFD).
By 2011 it was clear that gluten pathology outside coeliac disease was real. A consensus meeting summarised it thus:
A decade ago celiac disease was considered extremely rare outside Europe and, therefore, was almost completely ignored by health care professionals. In only 10 years, key milestones have moved celiac disease from obscurity into the popular spotlight worldwide. Now we are observing another interesting phenomenon that is generating great confusion among health care professionals. The number of individuals embracing a gluten-free diet (GFD) appears much higher than the projected number of celiac disease patients, fueling a global market of gluten-free products approaching $2.5 billion (US) in global sales in 2010. This trend is supported by the notion that, along with celiac disease, other conditions related to the ingestion of gluten have emerged as health care concerns.
Non Coeliac Gluten Sensitivity (NCGS)
The term Non Coeliac Gluten Sensitivity first appeared in the Lancet in 1978 in a paper by Ellis and Linaker entitled “Non coeliac gluten sensitivity?” [ref]. However, its use as a name for real medical condition has only been in accepted use since 2011 when gastroenterologists gathered in Oslo to reach a consensus on what this new gluten sensitivity phenomena should be called.
Prior to this meeting a plethora of terms had arisen to describe coeliac and gluten-related disorders, including: asymptomatic celiac, atypical, classical, latent, non-classical, paediatric classical, potential, refractory, silent, subclinical, symptomatic, typical, CD serology, CD autoimmunity, genetically at risk of CD, gluten ataxia, gluten intolerance, gluten sensitivity and gliadin-specific antibodies. It was a giant mess, with different researchers using different terminology. The Oslo meeting attempted to sort it out once and for all. I have summarised the key terminology they agreed on at at the end of this post, but for now, let’s focus on their definition of Non Coeliac Gluten Sensitivity:
The term NCGS relates to one or more of a variety of immunological, morphological or symptomatic manifestations that are precipitated by the ingestion of gluten in people in whom coeliac disease has been excluded.
Initially this appears to be very reasonable, but the phrase “immunological, morphological or symptomatic manifestations upon gluten exposure” has proven problematic. For example, studies since that meeting in Oslo have shown that exposure of the small intestine cells to gluten elicits morphological changes in everyone [ref]. Taken at face value the Oslo definition would classify the entire population as NCGS! Similarly, innate immune activation and raised wheat protein antibodies are being identified in a large percentage of the apparently healthy population. Consequently, in just three short years the working definition of NCGS has been narrowed to include only the symptomatic manifestations, that is, NCGS now only includes people who have gastrointestinal symptoms which improve on a gluten free diet (GFD).
Problems defining NCGS
NCGS is a very recently identified condition. Consequently, the medical understanding of it is still very much in its infancy, similar, perhaps, to where we were with coeliac disease twenty years ago.
There are three areas of uncertainty that make the definition of NCGS and its diagnosis difficult:
- The causative factor is still unclear. Multiple components of wheat and other grains are implicated (e.g. gluten, ATIs*, FODMAPS*). There may be different subsets of patients that react to different components.
- There is no definitive blood or histological test. Although NCGS patients typically have blood serum abnormalities e.g. 66% have raised IgG anti-gliadin antibodies (AGA) compared to 10% of the healthy population (see second video below). Diagnosis therefore, is based on symptom improvement on a gluten free diet (GFD)
- Diagnostic criteria are problematic. The current ‘gold standard’ diagnostic test requires worsening of symptom following a double blinded gluten challenge after symptomatic improvement on a gluten free diet. However, standardising this test is proving difficult (see first video below).
These problems make studying the condition difficult. Even the name NCGS is problematic: Non Coeliac Gluten Sensitivity should only strictly apply to patients who react to pure gluten, and would exclude those who react to ATIs*, FODMAPs* or other grain components. Consequently, some researchers use the term Non Coeliac Wheat Sensitivity, but this implies that other gluten containing grains, such as barley and rye are safe. The term I prefer, “Non Coeliac Gluten Containing Grain Sensitivity” is just too much of a mouthful. (Pun intended!)
* POSSIBLE COMPONENTS OTHER THAN GLUTEN CONTRIBUTING TO NCGS
Amylase trypsin inhibitors (ATIs)
These are part of the non-gluten proteins in wheat and related grains. A 2014 study demonstrated that they can cause intestinal inflammation via the innate immune system, providing an alternative mechanism in ‘gluten’ related pathology [ref]
Fermentable Oligo-Di-Monosaccharides and Polyols (FODMAPs)
These are short chain carbohydrates resistant to digestion that find their way into the colon where they can be fermented by microbes. The resulting gas can cause painful bloating and osmotic diarrhea. Wheat contains high levels of FODMAPs called fructans, which may contribute to some of the symptoms seen in NCGS. [ref] FODMAPs are also present in other foods such as onions.
There are many other grain components implicated in disease processes, which are considered potential candidates in NCGS, including wheat globulins, gluten ‘exorphins’ and wheat germ agglutinin.
Homing in on NCGS as a defined clinical entity
So as we have seen, to be classified as NCGS a patient has to have a reduction of symptoms when on a GFD where coeliac disease (CD) and wheat allergy(WA) have been ruled out. This on its own however is insufficient as patients know they are on a GFD and may be subject to the placebo effect. Many researchers are calling for a ‘gold standard’ test where suspected patients are subjected to a double blinded gluten challenge.
Enter the Salerno Experts group, who recently convened to develop a protocol for identifying NCGS (Diagnosis of Non-Celiac Gluten Sensitivity (NCGS): The Salerno Experts’ Criteria Nutrients, June 2015).
In the video below, from the 16th International Coeliac Disease Symposium 2015, one of the Salerno Experts, Dr Luca Elli, unpacks the complexities of studying NCGS.
- (0:00) Gluten and gastrointestinal functional disorders
- (1:15) No biomarkers for GI functional disorders; symptoms and treatment
- (2:25) Up to 50% placebo effect of food exclusion diets
- (3:15) NCGS definition
- (4:17) The need for a blinded gluten challenge
- (5:18) Problems in devising the protocol
- (6:45) Review of NCGS trials, protocols and findings
- (11:00) The GLUTOX trial results
- (13:04) Prevalence of NCGS in GLUTOX trial = 20% of GI Functional patients
- (13:30) Best practice for blinded gluten challenge
- (15:00) Conclusions
You will see from this video that NCGS patients are being identified from among patients with ‘Gastrointestinal functional disorders’ (e.g. IBS). Hence, current studies and prevalence estimates for NCGS do not include people who have gluten induced non-gastrointestinal symptoms, such as neurological or skin manifestations, yet in my clinic I regularly deal with patients that have these symptoms with only minor GI involvement, and who improve on a GFD. They are not coeliac. They are not NCGS. Oslo fails to give me a name for them! This is why the gluten iceberg goes deeper still – and that will be covered in part 3.
Dr Elli’s own study (the GLUTOX trial) found that just over 80% of the enrolled patients who had gastrointestinal functional disorders reported improvements when on a strict GFD. Of those that improved, only 1/3 of them relapsed when subjected to a randomised gluten challenge. The other 2/3, therefore may have been reacting to other components of the wheat, or were under the influence of a placebo effect. [Details: The GLUTOX Trial: Getting closer to identifying nonceliac gluten sensitivity]. EDIT (28/08/13): a similar proportion of patients responding to a blinded gluten challenge (1/3) has just been found in this study.
Regardless of these difficulties, the term NCGS has become a household name, at least among nutrition journalists and a subset of the public. UK doctors have yet to catch up. However, it is important to realise that even the current usage of the term ‘NCGS’ in the literature and media, by no means covers all research related to the pathology of gluten and grains. Hence, even with NCGS we have not reached the bottom of the gluten iceberg. In post 3 of this series I will look at the effects of gluten beyond coeliac and NCGS.
Case 1 – NCGS Skin Rash
Italy leads the field in the study of pizza pasta gluten related disorders
As the understanding of coeliac disease increased throughout the 2000’s specialist centres emerged all over the world. It is ironic, perhaps, that researchers from the great pasta and pizza eating nation of Italy have risen to prominence in the field of gluten related disorders. Both the videos and many of the references in this article are by Italian authors.
And here is another: a one year survey of suspected NCGS patients identified at 38 Italian centres [ref] found the following which is a typical picture of what other researchers find…
- 486 patients with suspected NCGS were identified in this 1-year period.
- The female/male ratio was 5.4 to 1, and the mean age was 38 years (range 3–81)
- The clinical picture included gastrointestinal and systemic manifestations (see graphs below)
- Reaction to gluten was quick: appearance of symptoms varied from a few hours to 1 day.
- Associated disorders included irritable bowel syndrome (47%), food intolerance (35%) and IgE-mediated allergy (22%) (i.e. classical allergy type manifestation).
- An associated autoimmune disease was detected in 14% of cases.
- 18% of patients had a relative with celiac disease, but no correlation was found between NCGS and HLA-DQ2/-DQ8 genes.
- IgG anti-gliadin antibodies were detected in 25% of the patients tested.
- Of patients who underwent duodenal biopsy; 69% showed normal intestinal mucosa, 31% showed mild increase in intraepithelial lymphocytes.
The two graphs below show the prevalence of symptoms identified in the Italian study. As you can see the range of symptoms associated with NCGS is vast, and like coeliac disease can involve many organ systems.
These gastrointestinal symptoms are similar to those seen in IBS, which has led some to say that NCGS is really just IBS. However, what distinguishes NCGS from IBS is the common occurrence of extra-intestinal (especially neurological) symptoms such as those below. (We will look at NCGS v IBS in more detail later)
If you or anyone you know have any of the above, it is certainly worth trying a strict gluten-free diet for a month to see if things improve. In fact, I would say go as far as to remove all grains, not just the standard gluten containing ones (wheat, rye and barley) as in my clinical experience, some people do not improve unless all grains are excluded.
Case 2 – NCGS symptoms are easy to miss before trying a GFD
The Prevalence of Non Coeliac Gluten Sensitivity
Based on the blinded-gluten challenge outlined above, the prevalence of NCGS appears to be about 6% in the general population, but the Salerno Experts group admit that they do not really know the true prevalence as they are still grappling with defining the condition.
On the other hand, in a recent UK survey the percentage of people self-reporting as gluten sensitive reached 13% [ref]. A similar study in Mexico found a similar number (12%) [ref] whilst a survey in Australia found 10% [ref].
The discrepancy between the diagnosed (confirmed) and self reported figures is often dismissed by the media as simply due to the “gluten-free fad”, as typified by this article in TIME magazine (click on image to read). I love that TIME has decided – ahead of the experts in this field – that anyone outside of the identified 6% NCGS who claims that on a GFD “they feel better, fitter, more energetic, that their withdrawn child has suddenly blossomed and that their man is healthier and happier” is probably just subject to the placebo effect!
“Is gluten sensitivity fad or fact?”
As discussed above, it is not clear yet whether it is the gluten, the carbohydrate content of grains, or other proteins in wheat and other grains which are causing symptoms. The likelihood is that different sub-groups are being triggered by different factors. Understanding exactly which aspect of wheat or grains causes which problems is still in its infancy, and researchers are saying:
Inaccurate attribution will be associated with suboptimal therapeutic advice and at least partly underlies the current gluten-free epidemic gripping the Western world
Although the prevalence rate for NCGS quoted by the experts is likely to change as research continues in the coming years, we should bear in mind that the diagnostic criteria of NCGS inevitably excludes certain people who would benefit from a gluten-free diet. Furthermore, there are different kinds of gluten-free diets: At one extreme all normal wheat based foods (breakfast cereals, cakes, bread etc) are replaced with their gluten-free simulacra (gluten free cereals, cakes, biscuits and bread), whilst at the other end additional meat, eggs, fruit and veg make up for the lost calories. It is the latter diet – a paleo or primal diet which excludes all grains, that I consider a true gluten-free diet. I would argue that the prevalence of NCGS would be much higher if this kind of gluten free diet were used in the diagnosis.
Biomarkers for NCGS
As already mentioned, there are currently no biomarkers for NCGS, however, that does not mean there are no serological abnormalities. In the following video Professor Umberto Volta, one of the Salerno Expert group and author of many published papers on matters around gluten, summarises the serum and tissue anomalies in NCGS.
- (3:10) IgG Antigliadin antibodies (AGA) are raised in 66% of NCGS patients. They fall within several months of a GFD, along with symptom resolution, whereas in coeliac disease they remain raised.
- (5:14) NCGS patients tend to have raised antibodoes to gliadin, glutenin, albumins and globulins, at similar levels to coeliac patients, but only coeliac patients have raised auto-antibodies (anti-deamidated gliadin and anti-tissue transglutaminase).
- (6:10) in NCGS and IBS patients on a GFD, peripheral blood mononucleated cells (PBMCs) responded to gluten exposure with increased levels of IL-10 and TNFα
- (6:40) in NCGS PBMCs responded to wheat extract with increased excretion of CXCL10 (interestingly, more so with modern wheat cultivars than ancient wheat varieties)
- (7:15) Compared to controls and IBS sufferers, NCGS patients had raised zonulin levels (an indicator of gut permeability) similar to coeliac disease patients.
- (8:00) NCGS patients had raised sub-mucosal mast cell density, again, similar to coeliacs, compared to healthy controls.
- (8:58) Intestinal deposits of anti-tissue transglutaminase found in some NCGS patients suggesting they may be at higher risk of developing coeliac disease.
- (10:03) No difference between NCGS and general population in HLA-DQ2/8. (i.e. no link to coeliac genetic markers)
- (10:48) Possibly NCGS show unique pattern of raised T-lymphocyte infiltration around villi
- (11:54) Summary: Although none of the above biomarkers is sufficently specific or sensitive for NCGS, they may contribute as part of a diagnosis.
Links between NCGS and irritable bowel syndrome (IBS)
As already mentioned NCGS and IBS share many symptoms. The key features of IBS are chronic, recurrent abdominal pain or discomfort, associated with disturbed bowel habit, in the absence of any structural abnormality to account for these symptoms. According to a review in BMJ Clinical Evidence (July 2015), the prevalence of irritable bowel syndrome (IBS) varies depending on the criteria used to diagnose it, but it ranges from about 5% to 20% of the US population. [ref]. Incredibly, as many as 42% of IBS sufferers claim to improve on a gluten free diet [ref].
Some authors go so far as to claim that all NCGS is really IBS, and that the problem is really with other wheat components such as FODMAPS (which are present in other foods not just grains) not gluten per se. [ref]. However, the Salerno Experts group, point out that “NCGS patients often report symptoms outside of the intestinal tract, e.g., headache and/or foggy mind, which cannot be accounted for by lactose, and/or FODMAPs intolerance.” [ref]
Four lines of evidence showing differences between IBS and NCGS
The following four lines of evidence not only show how NCGS is distinct from IBS in many ways, but it also gives insight into the range of damaging effects that gluten/wheat/grains can cause.
1. Bone loss and NCWS
Here is further evidence that IBS and NCWS* are distinct.
[*note: In two of the following studies authors use Non-Coeliac Wheat Sensitivity (NCWS or WS) as they employed a blinded wheat challenge to identify subjects]
This 2014 study looked at bone mineral density (BMD) in three groups of patients: 60 coeliacs, 75 NCWS and 65 IBS controls. They examined the BMD in the femoral neck and lumber spine of each patient.
As you can see from the graphs above the incidence of bone loss – either osteopenia or osteoporosis – is significantly higher in NGWS compared to IBS sufferers (as expected, coeliac patients had the highest incidence of the three groups). What the graphs don’t show, is that nearly half (46.6%) of the NCWS patients had low bone mineral density in at least one of the two sites checked, whereas half of coeliac patients had bone loss from both.
Compared to the IBS controls, the NCWS group also had higher frequencies of weight loss, anemia (90% had iron deficiency anemia), coexistent atopic diseases (which include asthma, eczema and hayfever) and a family history of coeliac disease than IBS controls.
2. Multiple food allergies in NCWS patients
As part of the initial screening for the above study, a double blind wheat challenge was used to seperate NCGS patients from IBS. However, the researchers went further, and conducted double blind challenges for a range of other foods.
30 of the 75 NCWS patients were found not only to react to wheat, but to cows milk proteins (casein). Moreover, eight of these thirty patients experienced IBS-like symptoms after open challenges with egg (four cases), tomato (three cases) or chocolate (two cases).
3. High levels of autoimmune disease found among NCWS
Hot off the press, a new study matched patients with diagnosed non coeliac wheat sensitivity(NCWS) with a similar number of IBS cases (who were not NCWS) and a similar number of coeliac cases. What they found is that among those with NCWS approximately 25% had autoimmune disease (mainly Hashimoto’s thyroiditis). This was similar to the number of autoimmune cases found in the coeliac group, whereas among the IBS group the rate was only 4% [ref], which is similar to the rate in the general population (i.e. 3%) [ref]
Another study found autoimmune diseases were present in 14% of NCGS patients, two thirds of whom had autoimmune thyroiditis. Psoriasis and Graves’ disease were frequently seen, whereas myasthenia gravis, atrophic autoimmune gastritis, scleroderma, type 1 diabetes mellitus, Crohn’s disease and IgA deficiency were infrequent. [ref]
4. Neurological symptoms in NCGS – e.g. depression
As already mentioned, one of the distinguishing features of NCGS is the common occurrence of neurological symptoms. These include headaches, anxiety, foggy mind, tiredness or simple lack of wellbeing.
Interestingly, a subset of patients excluded from a NCGS study category – for example if their IBS-like symptoms did not improve on a gluten-free diet – choose to stay on a GFD after the study, explaining that they simply “felt better”.
This prompted a study, published in 2014 [ref], looking at the effects of gluten on feelings of depression. They concluded “Short-term exposure to gluten specifically induced current feelings of depression with no effect on other indices or on emotional disposition. Such findings might explain why patients with non-coeliac gluten sensitivity feel better on a gluten-free diet despite the continuation of gastrointestinal symptoms.”
The current gastrointestinal focus of NCGS research may be missing more widespread effects of gluten and grains, making it likely that the quoted NCGS prevalence of 6% is likely to be an underestimate.
When Carroccio et al, compared 276 NCWS to IBS controls they found the following significant differences [ref]:
- a personal history of food allergy in the pediatric age
- coexistent atopic diseases
- positive serum anti-gliadin and anti-betalactoglobulin antibodies
- positive cytofluorimetric assay revealing in vitro basophil activation by food antigens
- a presence of eosinophils in the intestinal mucosa biopsies
These differences led them to suggest that NCWS patients “might be suffering from non-IgE-mediated food allergy”.
When considering research about conditions associated with NCGS, it is important to realise that the reverse is also true. In other words, people suffering with IBS, osteopoenia, food intolerance, depression or an autoimmune disease are at higher risk of having NCGS (and coeliac disease).
The Gluten-free diet
Anyone diagnosed with conditions linked to NCGS if not NCGS itself, should try a proper gluten-free diet to see if it will benefit them, but they should do the proper paleo grain-free version, not the half-baked gluten-free copy-cat version which continues to beguile the coeliac charities.
Support literature from Coeliac UK, for example, is jam packed with adverts for ‘gluten free’ products, products which have no place in a diet intended to actually nourish us. Indeed these so-called gluten-free products are nutritionally sub-standard and can contribute to deficiencies. A 2013 study into nutritional status of coeliac patients on a typical gluten-free diet found pre-diagnosis deficiencies in thiamin, folate, vitamin A, magnesium, calcium, iron and zinc were not resolved after 2 years on a standard gluten-free diet, in fact thiamin and vitamin A intakes declined. They concluded: “dietary inadequacies are common and may relate to habitual poor food choices in addition to inherent deficiencies in the gluten free diet” (my emphasis)
A gluten-free diet should be seen as an opportunity to move one’s diet away from highly processed foods, towards real, natural produce, as illustrated below. If the NHS and Coeliac UK embraced this ethos they would be doing a world of good, instead of attracting headlines like “NHS handed out £116m of gluten-free junk food on prescription in the past year“.
What this means for you – and why I say no one should eat grains
Using Professor Alessio Fasano’s figures (1% of the population is coeliac, 6% are NCGS) for each of us the chance of currently suffering from a gluten/wheat induced health problems of about 7%.
For an entirely avoidable health risk this is a huge percentage and represents a significant degree of misery, burden on the health service and risk of serious diseases in the future.
Although some people will consider a 7% personal risk to be small it starts to look different if you extend your consideration to the circle of people closest to you.
If you consider the ten most important people in your life – you and your nine nearest and dearest (spouse, parents, children and best friends), then the chance of at least one of you having a wheat/gluten induced health problem right now is greater than 50%. The chance of one of you having full blown autoimmune coeliac disease is 10%.
[For the maths geeks: 0.93^10=0.484, and 0.99^10=0.904]
Remember, you cannot tell in advance who will develop these conditions or when. There are no screening tests, and these conditions often go undiagnosed for many years, meaning that you or a loved one is likely to be suffering, and probably receiving inappropriate treatment, for a long time before the true cause is identified.
Whilst the whole extended family is complacently eating a normal wheat-based diet it will be almost impossible for anyone suffering with undiagnosed CD or NCGS to stumble upon the solution accidentally. Even if they start to suspect that they might be better off on a GFD social habits and pressure are likely to make it difficult for them to remain gluten free for long. Being the only one on a GFD is isolating and is one of the main reasons for poor adherence and relapses.
The only preventative measure you can take is for you and your loved ones to adopt a proper grain-free/gluten-free diet now. Done correctly it will actually improve your nutrition and health. Done together it will dispel the social isolation and stigma. What’s to lose?
The final point I will leave you with reflects researchers thoughts about why so many people are affected by such a common food as wheat and related grains:
Possibly, the introduction of gluten-containing grains, which occurred about 10,000 years ago with the advent of agriculture, represented a “mistake of evolution” that created the conditions for human diseases related to gluten exposure – Sapone, BMC medicine, 2013
Which is why a pre-agricultural, or paleolithic diet probably offers the best template for a healthy diet, which I would argue is a diet free of all grains – not just wheat, rye, barley and oats!
Finally, a case illustrating how quickly symptoms can improve with proper dietary advice:
Case 3 – A triathlete improves rapidly on a proper GFD
Table 1: The OSLO accepted definitions for gluten related disorders
|Non-classical CD||Presents without signs and symptoms of malabsorption.|
|Subclinical CD||Below the threshold of detection without signs or symptoms sufficient to trigger CD testing in routine practice.|
|Symptomatic CD||Clinically evident gastrointestinal and/or extraintestinal symptoms attributable to gluten intake.|
|Refractory CD||Persistent or recurrent malabsorptive symptoms and signs with villous atrophy (VA) despite a strict GFD for more than 12 months|
|Potential CD||Normal small intestinal mucosa who are at increased risk of developing CD as indicated by positive CD serology.|
|CD autoimmunity||Increased TTG or EMA on at least two occasions when status of the biopsy is not yet known.|
|Genetically at risk of CD||Family members of patients with CD that test positive for HLA DQ2 and/or DQ8|
|Gluten-related disorders||Used to describe all conditions related to gluten. May include gluten ataxia, DH, non-coeliac gluten sensitivity (NCGS) & CD|
|Non-coeliac gluten sensitivity||Is a condition in which gluten ingestion leads to morphological or symptomatic manifestations despite the absence of CD|
|Gluten ataxia||Idiopathic sporadic ataxia and positive serum antigliadin antibodies even in the absence of duodenal enteropathy|
|Dermatitis herpetiformis||Cutaneous manifestation of small intestinal immunemediated enteropathy precipitated by exposure to dietary gluten|
Whilst ‘only’ 1% of the population is strictly coeliac, there is mounting evidence that a much larger proportion are harmed by gluten. In this series of posts I’ll draw on the most up to date research which is revealing the incredible web of health implications linked to cereal grain consumption.
The gluten iceberg is a pertinent metaphor for this hidden, and much larger, mass of problems that lurk below the surface. As researchers begin to unravel the complexities of the sub-surface gluten iceberg it is sobering to realise that its dimensions remain largely unknown, yet evidence is now indicating that all of us are affected to some degree.
As a clinician I get to see first hand how a grain-free diet can be key to making significant medical progress in patients with complex and apparently unrelated medical problems. This enables me to provide additional and, I hope, interesting perspectives on this story.
PART 1 Coeliac disease – the tip of the iceberg
Coeliac disease affects at least 1% of the population of which 76% remain undiagnosed
Classic coeliac disease is a serious autoimmune enteropathy (gut disorder), with no cure. The only treatment is lifelong adherence to a gluten-free diet.
The true prevalence of coeliac disease in the population is hard to establish as many cases go undiagnosed, but a figure of 1% is frequently quoted for Western countries [ref]. However, this figure is creeping up, and in 2014 an article in the journal Gastroenterology stated “Screening studies have shown the prevalence in the European and North American population to be 1%–2%, and to be increasing over time.” [ref] A 2014 study in the Netherlands found that between 1995 and 2010 – a mere 15 years – biopsy-proven coeliac disease increased nearly threefold [ref].
Among some populations the prevalence is even higher: “It is now considered one of the most common genetic disorders in Europe and Asian Pacific region with a prevalence of up to 2.67% of the population. The true prevalence of celiac disease may still be underestimated.” [ref].
Even taking the more conservative figure of 1% that is a huge number: 650,000 people in the UK, 7.4 million across Europe, 3.2 million in the USA. At present you have no way of telling if you or one of your loved ones will one day be diagnosed.
Coeliac diagnosis – the complex criteria
The diagnosis of coeliac disease requires four of the following five criteria [ref]:
- Typical symptoms of coeliac disease
- Serum coeliac autoantibodies at high levels (anti-tissue transglutaminase; anti-endomysial antibodies)
- Human leukocyte antigen HLA-DQ2 or -DQ8 genotypes
- Coeliac enteropathy shown by small bowel biopsy
- Improvement on a gluten-free diet.
Why only four out of the five? Because of the many cases of non-typical coeliac disease where any of the above can be absent. Lets take each criteria in turn and consider the exceptions.
Non-typical coeliac can present as an exception to each rule:
1. Non-typical symptoms: It is estimated that 76% of coeliacs remain undiagnosed (see below). A proportion of these have few classic symptoms, yet have clear serum antibodies and genetic risk (HLA DQ2/8). A very recent screening study in the UK found that the prevalence of undiagnosed coeliac disease was 1.3%. [Article in press]
2. No serum coeliac antibodies: 6-9% of diagnosed coeliacs do not have serum antibodies [ref].
3. Absence of coeliac human leukocyte antigens: Likewise, although 94% of coeliacs have either HLA-DQ2 or DQ8 gentic type, 4% have variant DQ2.2 and 2% do not have any of the identified HLA genetic risk factors [ref]
4. No coeliac enteropathy evident upon biopsy: In 2001 a study looked at 10 suspected coeliac patients who had only mild intestinal inflammation without villous atrophy (damage to the gut lining). Yet they all had typical coeliac symptoms and HLA-DQ2 genotype. Eight of the 10 were positive for anti-endomysial antibodies (EMA), seven for anti gliadin antibodies (AGA), and nine for anti tissue transglutaminase antibodies (tTg); all of which normalized on a gluten free diet. Eight of them also had osteopenia – early stage osteoporosis – which is very common in coeliacs. [ref] A 2011 paper describes such patients as “potential coeliac”, and says that the condition is “well known”. It goes on to say that 30% of children with this presentation develop intestinal atrophy in 4 years [ref]
5. No improvement on a gluten free diet: Up to 2% of diagnosed coeliacs are classed as ‘refractory’ or ‘complicated’ because they do not improve on a gluten-free diet. Their prognosis is particularly bad, with a very high mortality rate: approximately 25% will actually die within 5 years of diagnosis. [ref]
This of course begs the question: what about individuals that meet only two or three of the coeliac criteria? They will not be considered coeliac, yet may suffer unless they too go on a gluten-free diet. Until recently they would have been dismissed as ‘not being coeliac’ and would have been dissuaded from trying a gluten-free diet. Hopefully this situation will change, as there is now a recognition that gluten can cause symptoms without coeliac disease. This newly recognised medical entity has been called non-coeliac gluten sensitivity (NCGS), and I will go into this in part 2, next week.
Risk factors for Coeliac
So, who’s at risk? Coeliac is a pretty horrible and common disease, so it would be nice to know if one was at risk of developing it or not. Unfortunately, this is not possible.
One of the main risk factors for coeliac disease is genetic, however, there is little point in having a coeliac gene test. Firstly, because as we have seen, 2% of coeliac cases occur in people without the coeliac genes, and secondly, nearly 40% of the general population carry the high-risk HLA-DQ2 or DQ8 genes, yet only 1 in 20 of them go on to develop the disease. What pushes one person over the edge into autoimmunity and not another is currently unknown. Some theories implicate infections, toxins, leaky gut – but for now at least, the jury is out.
So what about antibody blood tests? Tests for serum EMA and tTG antibodies are available on the NHS, but unless you have clear coeliac symptoms your GP is unlikely to oblige. Alternatively, a more comprehensive range of tests are available privately on request at clinics like mine. Whilst these tests are very reliable at identifying coeliac disease or cereal reactivity they only tell you that damage has already begun. If they come back negative they tell you nothing about your future risk.
The only absolute protection, therefore, is to avoid gluten in the first place – you simply can’t develop coeliac disease if you don’t eat wheat, rye and barley.
For the majority of people on a standard western diet, the first indication that they are developing coeliac is when they start getting symptoms. Trouble is neither they nor their doctors are likely to link these symptoms to gluten – not until significant damage has been done.
People with coeliac disease can exhibit a huge range of intestinal and extra-intestinal symptoms – see chart A and B below. These can easily produce a symptom picture that overlaps with other conditions, making diagnosis complicated and misdiagnoses all too common.
These, however, are only the most common symptoms. Before reading on take a moment to skim through the staggering list of symptoms and conditions that appear on the NICE recommendations for coeliac testing. (BTW – don’t expect your GP to have read these!)
If you took a look at the NICE guidelines, you won’t be surprised that in the UK an estimated 76% of coeliac cases go undiagnosed [ref].
The delay in diagnosis is reported to range from 4.5 years to 9.0 years. Patients may present on numerous occasions to both primary and secondary care without coeliac disease being considered. – Adult coeliac disease, BMJ 2007
Also, many are misdiagnosed, for example as suffering from irritable bowel syndrome (IBS). This is bad news as untreated coeliacs are at markedly increased risk of developing other diseases including multiple autoimmune diseases, cardiac problems and cancers.
[EDIT 28 June 2015]
The consequences of undiagnosed CD include not only underachievement and a 5-fold higher risk of non-Hodgkin’s lymphoma but also a 4-fold increase in all-cause mortality. – Aristo Vojdani, ISRN Allergy, 2011
Patient Case 1 – Late diagnosed coeliac with multiple early symptoms
How far does the damage go?
Many people assume, incorrectly, that coeliac disease is a mild condition – akin to food intolerance – but even when well controlled with a gluten-free diet it markedly increases risks of many other diseases. When untreated, the risks are even higher. Medical research into coeliac disease has burgeoned in the last twenty years and currently nearly one hundred new papers are published each month! Here are just a few such papers that indicate the range of problems linked to coeliac:
- Neurological effects: Increased Neuropathy Risk in Celiac Disease
- Hormonal effects: Increased rates of pregnancy complications in women with celiac disease
- Skeletal effects: Bone Microarchitecture Impaired in Active Celiac Disease
- Cardiovascular effects: Impaired aortic function in patients with coeliac disease.
- Gastrointestinal effects: The coeliac stomach: gastritis in patients with coeliac disease.
Furthermore, other autoimmune diseases are common among coeliacs – in one study [ref] of 381 adult patients the prevalence of concomitant autoimmune disease was 21%, including:
- dermatitis herpetiformis
- type 1 diabetes mellitus
- Crohn’s disease
- autoimmune hepatitis
- ulcerative colitis
It’s a simple fact: no other ubiquitous food is responsible for so many health problems for so many people – and we are still only considering the 1% tip of the iceberg.
Patient Case 2 – A grain-free diet helped resolve multiple symptoms
Why people with self identified gluten sensitivity may not be able to get a coeliac diagnosis
With the rise in popularity of the gluten-free diet, many people have experienced significant, sometimes unexpected, improvements in their health following gluten exclusion. However, they then find themselves in the difficult position of being required to go back on gluten for six weeks (knowing they will feel dreadfully ill again) so that they can receive the coeliac antibody tests and/or have a duodenal biopsy. If they remain gluten-free the tests are likely to produce a false negative, yet without these tests they are extremely unlikely to be diagnosed as coeliac. You can read a real-life story of TV actress Caroline Quentin who found herself in just this double-bind by clicking on the image below.
When gluten-free is not enough
Many coeliacs who go on a strict gluten-free diet do not recover fully. As mentioned above, those whose symptoms do not improve are considered refractory – and can have a very poor prognosis. However, there is another group where a standard ‘gluten-free diet’ is insufficient – those whose symptoms do improve, but who on biopsy show evidence of continuing intestinal damage. Whilst their symptoms may have improved, they are at risk of going on to develop overt refractory coeliac disease or other complications over time.
It is recognised that at least 5% of childhood cases have incomplete intestinal recovery after 2 years on a gluten-free diet, which can lead to significant malnutrition affecting growth and development. In the case of adult coeliacs, a 2010 study [ref] found very high numbers without intestinal recovery on follow-up. Among 241 cases who were checked, more than half had incomplete recovery, regardless of whether they had only partial or complete villous atrophy at their initial diagnosis.
The most obvious explanation would be lack of adherence to the diet – although in this study population adherence was considered very good. Even so, it underscores the importance of coeliacs being scrupulous in gluten avoidance. Hardly easy when, as one recent study found, approximately 20% of products labelled ‘gluten-free’ actually contained gluten above the limit of 20 mg/kg!
These results may be of concern, as gluten sensitivity is known to vary among celiac disease patients.
– Lee et al, Journal of food protection (Oct 2014)
To underscore the importance of trace gluten in ‘gluten-free’ products, in a 2013 study long term coeliac patients that had not recovered on a gluten-free diet after an average of 3 years were placed on a ‘Gluten Contamination Elimination Diet’. This diet avoided all commercial gluten-free products and common gluten contaminated foods, allowing only:
…brown and white rice; all fresh (no frozen, canned or dried) fruits, vegetables and herbs; fresh meats, poultry, fish and other non-processed protein sources. Unflavored, unseasoned dairy products are introduced on week 4.
All cereal grains aside from rice are prohibited. Processed cheeses, lunch meats, ham, bacon or other such processed, self-basted or cured meat products are not allowed.
– Justin R Hollon et al, BMC Gastroenterology, 2013
[Now that’s nearer to what I call a gluten free diet!] Of the seventeen patients that stuck to the diet, fourteen had complete resolution of symptoms.
Whilst contamination of gluten-free grains can be a problem, in some cases the persistence of symptoms or intestinal damage is because coeliacs are reacting to other grains such as corn (maize) [ref] or oats [ref], which are considered ‘safe’ for coeliacs as they do not contain gliadin. These grains are common in many of the so-called ‘gluten free’ products, so coeliacs on a standard prescribed GFD may be consuming these in significant amounts.
A substantial fraction of pediatric CD patients seem to not tolerate oats. In these patients, dietary oats influence the immune status of the intestinal mucosa with an mRNA profile suggesting presence of activated cytotoxic lymphocytes and Tregs and a stressed epithelium with affected tight junctions.
The idea that oats and corn can harm some coeliacs is not widely appreciated, yet it is less surprising when one considers that these crops are all part of the same botanical family of grasses – the Poaceae. This is an area that has received little attention from researchers to date, but makes the case for a paleolithic diet – which eschews all grains, not just wheat, rye and barley – all the more compelling.
A gluten-free diet can benefit non-coeliacs
First degree relatives of coeliacs are at heightened risk of developing the disease. However, even relatives who are symptom free may benefit from a gluten-free diet. In a 2014 study, screening for endomysial antibodies was performed on first degree relatives of known coeliacs, and those that were positive, but symptom free, were randomised to a normal or gluten-free diet. Those on the gluten-free diet benefited “as measured by extensive clinical, serologic, and histologic parameters”. The authors point out that:
This randomized approach showed that subjects who thought they were asymptomatic experienced improvement in several objective disease scores upon adopting a GFD. These findings… suggest that the patients may in fact have accepted mild symptoms as normal and recognized them as abnormal only later when on the diet. [Gastroenterology, 2014]
In other words, there are people who are not classified as coeliac, yet have been living with gluten related health problems, but are unaware of their symptoms. They only realise once they try a gluten free diet and find they feel better.
Patient Case 3 – A relative of a coeliac who benefited from a gluten-free diet
And with this last study, we have left the tip of the gluten iceberg where coeliac disease exists and are beginning our descent into the murky sub-surface world where gluten’s effects spread out into a much larger proportion of the general population.
Next week: PART 2 – Non Coeliac Gluten Sensitivity
- At least one percent of the population has coeliac disease, and the numbers have increased in the last twenty years. Three quarters of coeliacs remain undiagnosed. You cannot predict if it will be you next.
- Coeliac is an incredibly complex disease with a high rate of misdiagnoses.
- The co-morbidities associated with coeliac disease are serious and far reaching indicating multiple pathological effects of wheat, gluten or grains in general.
- Many people who are excluded from a formal coeliac diagnosis may benefit from a gluten free diet.
- A grain-free, not just gluten-free diet, is the only guarantee of lifelong protection.
I was reading an article in the Wall Street Journal, entitled “Is a Paleo Diet Healthy?” which is based around two opinion pieces: on the “Yes” side is naturopathic physician Kellyann Petrucci, whose argument is supported by recent studies and scientific evidence. The counter argument, in the “No” camp comes from Professor Marion Nestle, who relies almost entirely on unsupported assertions such as:
What we know for sure is that the fundamental tenets of nutrition are variety, balance and moderation. The fewer kinds of foods consumed, the greater the chance of nutrient deficiencies. So while it is certainly possible to eat healthfully on a paleo diet, restricting whole groups of relatively unprocessed foods can make this more challenging.