- There is growing epidemiological evidence for an causative link between diet and the inflammatory bowel diseases, Crohn’s disease and ulcerative colitis, which are increasing in incidence around the world in parallel with increasing westernisation of societies. Because of this it has been suggested that the inflammatory bowel diseases are lifestyle diseases.
- Meat and certain fats have been implicated particularly in their causation.
- Fruits, vegetables and fibre appear to be protective.
- Anecdotally there is a growing number of people claiming to have cured their IBD by changing their diet. One diet that has received attention online is the low fat raw vegan diet championed by David Klein (author of Self-Healing Colitis and Crohn’s), who claims that 90% of patients heal in 3-8 weeks, but has not formally published his results.
- Only one small dietary intervention study has been carried out to date, which showed a significant beneficial effect for a semi-vegetarian diet (meat no more than once per fortnight, fish no more than once per week)in Crohn’s disease. 94% of those following the diet remained in remission at 2 years, compared to 33% of those not following it. However this was neither randomised nor controlled. There has been a call (by Professor J. Rhodes at the University of Liverpool in 2013) for more such studies that are bigger and better designed.
- Current dietary advice for patients may involve trials of the elimination of wheat or dairy, or the six-food elimination diet. Meat exclusion is never advised.
- Current short term dietary advice when symptomatic includes the low-residue diet, which is the exact opposite of what the evidence suggests would be beneficial for preventing relapse. Indirect negative messages are also being given out in the form of unhealthy hospital food. This is likely to confuse patients and impair their efforts to eat more healthily.
- There has also been a call for dietary advice based on best available evidence (again, from Professor Rhodes). This means that patients should be made aware of the results of research that has been done, even if those results are not conclusive. To speak metaphorically for a moment, if the weather vane is currently pointing north, we should advise heading north, unless or until the wind changes. After all, if we do what we have always done, we will get what we’ve always got…
Natural Hygiene and Self Healing Colitis and Crohn’s
Recently I came across a book entitled Self Healing Colitis and Crohn’s by David Klein (1). The book is based on the principles of Natural Hygiene: a system of thought that holds that the human body is a self-healing biological system, operating according to certain physiological laws, that given the right conditions will work to rectify whatever challenge to its integrity it faces.
No great surprises so far: we know that the human body has the ability to heal wounds and mend broken bones, and contains a complex immune system that seeks to deal with disease-causing bugs and remove cancer cells.
We also know that sometimes it fails. Sometimes the bones are too broken, the bugs too many or too virulent, the tumour cells too rapidly dividing. Sometimes it needs help, and I have no problem with this.
But (and it is a big BUT), we don’t really understand why sometimes it succeeds and sometimes it fails. We don’t know how to predict whether it will succeed or whether it will fail. Who will live, and who will die.
This makes us afraid, and fear begets a knee-jerk response to treatment: we (doctors) treat early, and we treat aggressively; we assume that everyone is the one who will die. We rarely allow the bodies of our patients the time they need to heal; we rarely watch and wait; we rarely employ masterful inactivity as a treatment strategy. Increasingly we fear that if we let patients go out into the big wide world without having done everything we conceivably could, one of them won’t come back for review because they will be dead. Or they won’t come back for review because they are neglectful of their own health, or do not realise the danger they are in – and then, shortly afterwards, they will be dead.
Because the medical paradigm is always to treat immediately, we never allow time for the body to heal itself, nor do we pay any attention to the needs of the body that, when met, allow it to complete this task effectively.
Superficially, many of the assertions of Natural Hygiene seem not dissimilar to what many now think of as lifestyle factors in health and disease. A good diet, adequate sleep, avoiding harmful addictive substances, taking plenty of exercise, maintaining our mental and emotional good health, breathing clean air and drinking clean water, and avoiding exposure to harmful chemicals and radiation: few people would argue with these basics.
Except that Natural Hygiene suggests that the good diet the human body needs for fully functioning immunity is a low fat (<10% of total calories from fat) raw vegan diet that obtains the majority of its calories from fruit and the majority of its minerals from green leafy vegetables (this being the diet our bodies originally evolved to consume). Suddenly we are being significantly challenged. Add to this the view that harmful addictive substances such as caffeine, alcohol, nicotine and sugar, as well as the opioid breakdown products of gluten (in wheat) and casein (in dairy products), should be excluded completely, and you have a position that is extremely challenging indeed to the status quo (the food industry, the pharmaceutical industry, pubs, cafes, butchers, bakers, our cultural heritage and the nurturing food our mothers made us). That is before we add in any discussions about pesticides, electromagnetic fields, or the definition of plenty.
The low fat raw vegan diet excludes all of the foods on the six food elimination diet (wheat, soya, nuts, fish, dairy and eggs) and also excludes meat and all foods requiring cooking to make them palatable (e.g. rice and potatoes). This is more-or-less the diet I am currently consuming and it is not difficult, although it does require some adjusting to. It consists of large amounts of a wide variety of nutrient-dense fruits and vegetables, particularly salad vegetables and leafy greens. It may also include raw carrots and sprouted legumes. My children consume a supplemented (with a B12-containing multivitamin and DHA/EPA capsules) high-raw, though not exclusively raw, vegan diet and are in excellent health. They are growing normally without excess weight and neither of them has ever been in hospital, or taken (or needed) any medications other than Calpol. It might be simple good luck of course (touch wood), but I am inclined to think there may be more to it than that. The diet is flavourful and palatable to both adults and children alike: children particularly love to eat sweet, ripe fruit, which they are naturally attracted to. They rarely reject it, and it always makes me feel very sad to see parents rationing fruit – taking it away from their children or telling them off for eating too much of it. Dishes can be simple or complex, with options to suit most palates and budgets. They may include fresh juices, soups, dips or smoothies, and slightly more fat (e.g. from avocado, coconut, nuts and seeds) for younger children.
This week I have seen about three or four young people between the ages of two and thirteen who consume no fruits or vegetables at all. They are extreme cases, but sadly not that unusual in modern western society. It is rare for me to meet a young person who regularly hits the government’s minimum target of five portions of fruits and vegetables per day, let alone exceeds it. Perhaps they do exist, but they are not coming to the hospital – but equally this may simply represent the general diet for our population of children.
David Klein claims to have been cured of his ulcerative colitis by employing the diet and lifestyle recommendations of Natural Hygiene. He now runs the Colitis and Crohn’s Health Recovery Center in the US. He claims to have treated thousands of patients, and that over 99% of them have healed. On his website (2) he states that:
“About 90% of our clients who follow my guidance heal up within 3 to 8 weeks, depending on their condition and how well they apply program.”
David Klein is not a medical doctor (he has a background in engineering), and seems relatively untroubled by any imperative for facts or figures to back up his claims. He neither quotes any scientific evidence nor appears to be seeking it (a shame, because hard data would make the world of difference to patients), and his book could even be a complete work of fiction. However the many positive testimonials in it and scattered across the internet do suggest otherwise, and they are bothering me. The theoretical plausibility of the basic assertions of Natural Hygiene (if not some of the more creative explanations for its observed effects – it is one thing to establish that it works, entirely another to establish why it works) is bothering me. It seems to me to make sense.
Meanwhile the medical profession, and the profession of gastroenterology in particular, does not appear to be too bothered by what causes IBD (and therefore the factor or factors that must be removed or eliminated in order for healing to take place), and there seems to be no suggestion that it could ever be anything other than a chronic, life-limiting condition that relapses and remits but never goes away, requiring immediate and potentially lifelong treatment with unpleasant drugs with an impressive array of side-effects.
There is an obvious paradox in using immunosuppressants to treat a condition resulting from excessive activity of the immune system (inflammation). In health, inflammation is part of the body’s efforts to rid itself of foreign invaders. Generally these are recognised by proteins on the surfaces of bacteria or viruses, and it is no coincidence that it is also proteins that are responsible for food allergies (which are inappropriate immune responses to foreign proteins). Excessive dietary protein (more than 12% of total calories) has been implicated in animal studies in the promotion of tumour development (this was particularly demonstrated using the milk protein casein), and the consumption of animal protein (which may be recognised as foreign to the organism precisely because of its similarity to our own protein) more generally has been implicated in the development of autoimmune conditions such as rheumatoid arthritis. Consumption of acidic animal protein has also been shown to increase calcium excretion in the urine, increasing the production of kidney stones and (it has been suggested) resulting in the positive correlation between calcium consumption (mostly from dairy) and rates of hip fracture (resulting from osteoporosis) that exists globally.
A low fat raw vegan diet contains between 5 and 10% of total calories from plant proteins (8-10% being our physiological requirement as demonstrated by nitrogen balance studies, while intake for those consuming a western diet is between 11 and 22%), so a plausible mechanism exists for its putative action. By removing potentially pro-inflammatory proteins from the diet, and at the same time providing large quantities of antioxidants and phytochemicals required for optimum functioning of the immune system, the body is given the best opportunity of achieving healing and best health. Whether the condition is being triggered by an infectious agent or a pro-inflammatory protein, the immune system is required to respond to this invasion. As long as the causative agent remains present, the immune system will remain on high alert. High inflammatory markers do not tell us that the immune system is breaking down or malfunctioning. They tell us that it is working all out to rid the organism of threat. Something is triggering this, even if we do not know exactly what that something is.
In our unit most Crohn’s disease patients start their treatment soon after diagnosis with Modulen feeds. Modulen IBD is made by Nestlé (hardly the greatest ethical record in the world – not to be relied upon either to provide products in the patient’s best interests or to tell the truth) and is a 100% casein-based protein powdered formulation that provides 15% of total calories from protein, 43% from carbohydrates (27% sugars) and 42% from fat (25% MCT). They consume only this for several weeks, and many of them do get better. Of course, this is not a long-term solution, and once remission is achieved all patients return to their “normal diet”. After a while most of them relapse, and eventually they move on to more aggressive drug treatment.
Why does Modulen IBD work? It is hypothesised that it gives the GI tract a rest, by providing nutrients in an easily absorbable form (small molecules such as sugars rather than starches for example). Of course an equally plausible theory is that aetiological agents present in the “normal diet” are removed when feeds are started, thus allowing healing. At the end of treatment these agents are reintroduced and eventually relapse occurs (as you might expect if our hypothesis is true). Because no sustainable dietary solution is provided, cure is impossible.
I cannot understand how you can treat diseases of the GI tract without paying close attention to what is being fed into that tract. Most of our hospital patients are being fed terrible food. Even by conventional standards, chicken nuggets, chips, fish fingers, baked beans, and the like could hardly be regarded as nutritionally adequate.
I am not making an argument here for a dietary/alternative approach to treatment to the exclusion of all pharmaceutical or surgical approaches, which have their place. But I do believe that to subject children and young people to drugs and operations with serious side-effects and life changing results (as for the four patients I have been involved with recently who are facing the possibility of colectomy) without so much as discussing dietary options, let alone giving them a fair (and ideally properly evaluated) trial, is – well let’s just say it’s not a great thing to do. If it was my child I would be asking for a gastrostomy in order to feed them huge quantities of blended/juiced raw fruits and green vegetables. Assuming they were refusing to drink my concoctions of course! I am not joking.
Within the medical profession I may be perceived as radical in my views, but I remain fiercely committed to the value of good quality scientific evidence for any intervention. That said, I am gravely concerned by the very substantial effects of the most insidious, unrecognised and significant form of bias in scientific research: the bias that informs which studies are done, and which are not.
There is a very great difference between a lack of evidence for an intervention, meaning good quality studies have been done and shown no effect, and the lack of evidence resulting from the fact that no studies have ever been done. Currently, most medical research focuses on drug development, because drugs can be sold at a profit, thereby more than covering the costs of their development. By and large the field of nutrition as a therapeutic intervention has received little to no attention at all, since healthy diets and healthy people profit no-one. This realisation has led to something of a crisis of faith for me as regards scientific “proof”. What claims can now be believed? According to a BMJ survey, 13% of UK based scientists or doctors are aware of colleagues intentionally altering or fabricating data during their research or for the purposes of publication. And having spent some time critically appraising papers for this blog, I am increasingly aware of how design influences data and how data can be misconstrued, either by the researchers themselves or by the media and other professionals who prefer a certain interpretation.
I do not think I am being naïve in raising this issue – I do understand the clinical difficulties involved in talking to patients about diet. I talk to almost all my patients about diet, and recent reactions have included shrugging of shoulders, bursting into tears, and getting angry and defensive. All of these reactions highlight the scale of the problem, and to some extent explain the avoidance of the issue by most doctors.
But whether or not patients are willing to consider the role of diet as a contributing factor to their poor health and overt disease (some will, and some will not), doctors should. We should consider the biological needs of the human organism, and the effects of failing to provide for those needs in terms of the failure to maintain biological integrity that we call all manner of diseases: that we currently treat as multiple independent entities. We must consider the issue of host susceptibility as much as we consider the virulence of bugs or the aggressiveness of cancer cells.
IBD in Asia
Apparently our medical colleagues in India have noticed a rise in rates of IBD in recent years. Not so long ago this was a condition that was rarely, if ever, seen.
A recent systematic review (Prideaux et al., 2012) (3) has highlighted the rapidly increasing incidence of IBD in Asia over the past two to four decades. There is also an increased incidence in migrants from Asia to the West. Increased contact with the West, westernisation of the diet, increasing antibiotic use, improved hygiene, vaccinations or changes in gut microbiota were suggested as possible explanations for this change. On the subject of diet specifically, the article has this to say:
“Changes in lifestyle in Asia during the last two decades have resulted in a more “westernized” lifestyle, with increased consumption of refined sugar, fat and fast food. Several of these dietary factors, such as linoleic acid (4) and animal protein, have been associated with an increased risk of IBD, particularly UC, in healthy women in Western studies […] Dietary studies in Asia have mainly been conducted in Japan. In a case control study, Western foods (such as margarine) were significantly associated with an increased risk of UC (5). Increased intake of polyunsaturated fatty acids, particularly n-6 polyunsaturated fatty acids, and animal protein parallel the increased incidence of CD in Japan (6) […] A more recent case-control Japanese study showed that a higher consumption of sweets, sweeteners, fats, fatty acids and oils were associated with an increased risk of CD and UC (7).
IBD and Animal Protein
In 2004 a prospective cohort study (8) that recruited 191 patients with UC reported the odds ratio* of relapse for the top tertiles of intake of all meat (OR 3.2, 95% CI 1.3-7.7) and red or processed meat (OR 5.19, 95% CI 2.1-12.9), compared to the bottom tertiles. They concluded that high meat intake is associated with likelihood of relapse, but that further studies are needed to determine if reducing intake would reduce relapse frequency.
*[N.B. the odds ratio is the ratio of the odds of getting the disease in those exposed to a particular factor (in this case meat) compared to those not exposed (or not exposed so much). If there were no difference between the two groups the odds ratio would be 1. If (as here) the odds of getting UC in those consuming lots of meat was three times that of those consuming little, the odds ratio would be 3:1, or simply expressed as 3)
In 2010 the relationship between protein intake and IBD incidence was reported for a prospective cohort of 67,581 French women aged 40-65 years (9). “High protein intake, specifically animal protein, was associated with a significantly increased risk of IBD. (hazard ratios for the third vs. first tertile and 95% confidence interval being 3.31 and 1.41-7.77 (P trend=0.007), and 3.03 and 1.45-6.34 (P trend=0.005) for total and animal protein, respectively). Among sources of animal protein, high consumption of meat or fish but not of eggs or dairy products was associated with IBD risk.”
Also in 2010 a retrospective case-control study of 83 new cases of IBD (41 UC, 42 CD) and 160 healthy controls, for the 61.4% of cases who did not modify their diet prior to diagnosis (on the basis of symptoms), reported that “moderate and high consumption of margarine (OR=11.8 and OR=21.37) was associated with ulcerative colitis, whilst high consumption of red meat (OR=7.8) and high intake of cheese were associated with Crohn’s disease.” (10)
In 2011 a systematic review of dietary intake and the risk of developing IBD (11) reported that “the incidence of inflammatory bowel disease (IBD) is increasing. Dietary factors such as the spread of the “Western” diet, high in fat and protein but low in fruits and vegetables, may be associated with the increase.”
“Nineteen studies were included, encompassing 2,609 IBD patients (1,269 Crohn’s disease (CD) and 1,340 ulcerative colitis (UC) patients) and over 4,000 controls. Studies reported a positive association between high intake of saturated fats, monounsaturated fatty acids, total polyunsaturated fatty acids (PUFAs), total omega-3 fatty acids, omega-6 fatty acids, mono- and disaccharides, and meat and increased subsequent CD risk. Studies reported a negative association between dietary fiber and fruits and subsequent CD risk. High intakes of total fats, total PUFAs, omega-6 fatty acids, and meat were associated with an increased risk of UC. High vegetable intake was associated with a decreased risk of UC.”
Data from the Nurses Health Study, published in 2013 (12), which followed up 170,776 women over 26 years, concluded that “long-term intake of dietary fiber, particularly from fruit, is associated with a lower risk of Crohn’s disease but not ulcerative colitis”. Regarding Crohn’s disease, they reported that: “compared to the lowest quintile of energy-adjusted cumulative average intake of dietary fiber, intake of the highest quintile (median of 24.3 g/day) was associated with a 40% reduction in risk of CD (multivariate HR for CD, 0.59; 95% confidence interval [CI], 0.39–0.90). This apparent reduction appeared to be greatest for fiber derived from fruits; fiber from cereals, whole grains, or legumes did not modify risk.”
In the UK most people do not eat enough fibre (the average intake is 12.8g/day for women and 14.8g/day for men). The recommended average intake for adults is 18g (NSP) per day (13). For comparison a low fat raw vegan diet can provide upwards of 40g/day depending on calorie requirements and assuming these are met. If you take the view (as I do) that a raw vegan diet most closely approximates the natural diet of the human species (debatably +/- very small/occasional amounts of raw animal matter such as insects, raw eggs or fresh, wild-caught meat, constituting not more than a few percent of total calories), then any amount of fibre less than this is going to be inadequate and ultimately result in disease.
It has been suggested that one mechanism that might explain these observed effects is the reduction in beneficial bacteria in the intestine brought about by the consumption of animal protein and animal fats (14). Another theory, also discussed in the Nurses Health Study paper, is an effect of fibre consumption on the maintenance of intestinal barrier function (15, 16), preventing the adherence, translocation and penetration of bacteria under normal conditions.
IBD and Diet on YouTube
Tonight I have been watching YouTube videos made by people who claim to have healed their IBD with diet. The internet is an interesting thing. Ten years ago we could never have known these people existed. Now they are rambling away into their phones while watching the match, and telling their stories. What new kind of evidence is this? Could there be any science to it? Could one take a scientific approach, and search for, say, ulcerative colitis and diet on YouTube and see what comes up – what are the diets people are saying have worked for them – are so excited about that they are moved to broadcast to the world? Should we be listening, and designing studies around our findings? It might be a new and interesting form of qualitative research, which seeks to dissect narratives and identify recurring themes. There are different kinds of knowing in the world – different kinds of evidence. Theories may be just that, but I always come back to the immortal words of my A-level chemistry teacher (said with a thick Glaswegian accent): “science is about models girls”. She went on to explain that in science we never know anything for sure, nor should we ever claim to. We just keep constructing models and testing them against reality. When they don’t hold up, we refine them and hopefully move them a little bit closer to the truth. Big studies are great, but in the absence of big studies perhaps we can do little studies – studies of even one individual, where we really listen to what they are saying.
This is not an unbiased list – it has been cherry-picked for my own interest – but here are a few such stories, that it may be worth paying attention to. What is going on here?
My Healing Journey (from ulcerative colitis to true health) Pt 1
My Healing Journey (from ulcerative colitis to true health) Pt 2
Ulcerative Colitis Cured By Raw Food
Heal Crohn’s disease and Colitis Naturally!
Health Crisis to Healing, My story.
Ep:134 Crohn’s disease?? GO RAW! Take control of your health!
Crohn’s Disease Cured & 20 Kilos Weight Loss Raw Till 4
Best Diet to Heal Crohn’s Disease and Top Foods You Must Avoid
Super Juice Me with Jason Vale
“No illness which can be treated by diet should be treated by any other means.” – Maimonides [Medieval Jewish Philosopher and Physician]
Today I came across the following video on Dr Michael Greger’s website NutritionFacts:
Dietary Treatment of Crohn’s Disease: http://nutritionfacts.org/video/achieving-remission-of-crohns-disease/
In it Dr Greger reports on a non-randomised, non-controlled intervention study carried out in Japan, in which 22 Crohn’s disease patients were asked to eat either their normal diet or a Japanese-style semi-vegetarian diet for two years (17). 16 patients followed the diet and six did not. There was a highly significant difference between these two groups (p=0.0003) for rate of relapse at two years. The remission rate was 94% (15/16) at two years for the semi-vegetarian group, compared to 33% (2/6) for the omnivorous group. The authors reported that to the best of their knowledge this was “the best result in relapse prevention” ever reported. The authors conclude that:
“this study shows that a semi-vegetarian diet is safe and has a preventive effect against relapse of Crohn’s disease […] This supports our notion that IBD is a lifestyle-related disease that is mediated mainly by a westernized diet. The concept that IBD is a lifestyle-related disease is lacking in present practice. We believe that without introduction of this concept, a major breakthrough in the prevention of relapse in Crohn’s disease is not attainable […] Our new findings require verification in large, randomized, controlled clinical trials.”
I think these conclusions are a little premature given the extremely small scale of the study and its lack of either randomisation or a control group. However it seems to be the only such study in existence at all, and the results are sufficiently suggestive to warrant further research. It lends further support to my earlier theories, and as the authors point out, the intervention is entirely safe and without side-effects. Personally I would prefer to study a plant-based (at least wholly vegetarian, or ideally vegan) diet that is low in fat, protein and refined carbohydrates and high in whole/raw foods, for optimal results, but of course a balance would need to be achieved between likelihood of success and likelihood of compliance. Focusing on what to include rather than what to exclude may be helpful in this regard. Attention to education and motivational support would be necessary, as well as correlating results with actual dietary composition (dose-response) achieved rather than simply to allocated group.
Of course in real clinical practice I would prefer to offer families information about the dietary components that it is hypothesised may be responsible for their child’s disease, and then have a supportive goal-setting conversation with them about what they consider realistic and would like to achieve. Goals may change over multiple consultations, with progress towards dietary change being made in a two-steps forwards, one-step back fashion over a period of time. This is quite different to the random allocation to a prescribed diet model necessary for a clinical trial. However it would be possible to randomly allocate patients to either normal diet or supportive counseling with the aim of encouraging the ultimate adoption of a certain pre-defined recommended diet. Blinding would of course not be possible, as with all trials of dietary interventions.
The Low-Residue Diet
It is worth noting here that the diet I am suggesting above, for long-term remission of IBD, is the polar opposite of the low-residue diet that is commonly recommended for consumption during a flare. The low-residue diet limits high fiber foods such as whole grains, nuts and seeds, raw or dried fruits, and vegetables. It includes refined flour products (e.g. white bread/rice/pasta), meat, milk and eggs, margarine, mayonnaise, honey, plain cakes and biscuits, ice-cream, and well cooked fruits and vegetables that have been peeled and de-seeded, or soft fruits such as bananas, avocado or melon.
Overall this diet is likely to be a disaster for healing IBD. It excludes everything the body needs (phytonutrients, antioxidants etc.) and includes all the foods that have been positively correlated with IBD rates. I am not sure if there is any scientific basis for it or if it has been developed empirically based on cumulative patient experience, but almost certainly it sacrifices genuine long-term healing for short-term symptom relief. Focusing on soft, non-acidic fruits, steamed/pureed vegetables and fresh raw fruit and vegetable juices and smoothies would strike me as better advice for those who have active ulceration and inflammation, until symptoms subside.
Evidence-based Dietary Advice for Patients
I was interested to discover a paper published in 2013 jointly by the Department of Gastroenterology, Institute of Translational Medicine, University of Liverpool, and the Department of Dietetics at the Royal Liverpool University Hospital (18), quoted on Dr Greger’s video entitled “Preventing Crohn’s Disease with Diet”: http://nutritionfacts.org/video/preventing-crohns-disease-with-diet/
The authors conclude that “there are some clear signals that diet is relevant to IBD pathogenesis, yet frustratingly little good evidence from interventional studies. Published guidance provided by professional bodies varies considerably between different sources and is often based on consensus of opinion rather than evidence […]
There is little evidence from interventional studies to support specific dietary recommendations. Nevertheless, people with IBD deserve advice based on ‘best available evidence’ rather than no advice at all, although dietary intake should not be inappropriately restrictive. Further interventional studies of dietary manipulation are urgently required […]
There is a clear need for greater priority to be given to the conduct of high-quality interventional studies of dietary manipulation in IBD so that we can obtain a much clearer understanding of the associations between diet and IBD.”
They summarise that for Crohn’s disease patients a diet low in animal fat, processed fatty foods and insoluble fibre can be recommended, with supplemental vitamin D. For UC a diet low in meat and margarine can be recommended. They raise the usual concern regarding calcium intake to justify the continued consumption of dairy products, despite the positive correlation with hip fracture and the negative effect of a high protein diet on calcium balance mentioned above.
And to summarise my thoughts, I believe that we should be having robust conversations with patients about radical dietary change (and offering the necessary support, education and monitoring, and plugging them in to well designed clinical trials) – before we commence drugs with significant side-effects or remove their colons.
1) Self Healing Colitis and Crohn’s, 4th Edition. David Klein 2014.
2) The Colitis and Crohn’s Center: http://colitisandcrohnscenter.com/health-facts/health-facts-99-success-rate/ Accessed on 27th July 2015.
3) Inflammatory bowel disease in Asia: A systematic review. L. Prideaux et al. Journal of Gastroenterology and Hepatology, Vol.27(2012);p.1266-1280.
4) Linoleic acid, a dietary n-6 polyunsaturated fatty acid, and the aetiology of ulcerative colitis: a nested case-control study within a European prospective cohort study. Tjonneland A. et al. Gut 2009 Dec;58(12):1606-11. doi: 10.1136/gut.2008.169078. Epub 2009 Jul 23.
5) Dietary and other risk factors of ulcerative colitis. A case-control study in Japan. Epidemiology Group of the Research Committee of Inflammatory Bowel Disease in Japan. Kurata JH. J. Clin. Gastroenterol. 1994; 19: 166–71.
6) Epidemiologic analysis of Crohn disease in Japan: increased dietary intake of n-6 polyunsaturated fatty acids and animal protein relates to the increased incidence of Crohn disease in Japan. Shoda R et al. Am. J. Clin. Nutr. 1996; 63: 741–5.
7) Dietary risk factors for inflammatory bowel disease: a multicenter case-control study in Japan. Sakamoto N et al. Inflamm. Bowel Dis. 2005; 11: 154–63.
8) Influence of dietary factors on the clinical course of ulcerative colitis: a prospective cohort study. Jowett SL et al. Gut, 2004 Oct;53(10):1479-84.
9) Animal protein intake and risk of inflammatory bowel disease: the E3N prospective study. Jantchou P. et al. American Journal of Gastroenterology.
10) Pre-illness changes in dietary habits and diet as a risk factor for inflammatory bowel disease: A case-control study. World Journal of Gastroenterology 2010 September 14; 16(34):4297-4304
11) Dietary intake and risk of developing inflammatory bowel disease: a systematic review of the literature. Hou JK et al. Am J Gastroenterol. 2011 Apr;106(4):563-73. doi: 10.1038/ajg.2011.44.
12) A prospective study of long-term intake of dietary fiber and risk of Crohn’s disease and ulcerative colitis. Ananthakrishnan A.N. et al. Gastroenterology 2013;145:970-977
13) British Nutrition Foundation – Dietary Fibre: http://www.nutrition.org.uk/nutritionscience/nutrients/dietary-fibre.html Accessed on 1st September 2015
14) Missing environmental factor in inflammatory bowel disease: Diet-associated gut microflora. Inflammatory Bowel Disease August 2011;Vol.17, No.8
15) Dietary clues to the pathogenesis of Crohn’s disease. Pfeffer-Gik T. and Levine A. Digestive Diseases 2014;32:389-394
16) Translocation of Crohn’s disease Escherichia coli across M-cells: contrasting effects of soluble plant fibres and emulsifiers. Roberts C.L. et al. Gut 2010;59:1331-1339
17) Lifestyle-related disease in Crohn’s disease: Relapse prevention by a semi-vegetarian diet. Chiba M. et al. World Journal of Gastroenterology 2010 May 28;16(20):2484-2495
18) Review article: evidence-based dietary advice for patients with inflammatory bowel disease. E. Richman and J.M. Rhodes. Alimentary Pharmacology & Therapeutics 2013;38:1156-1171