Max Schmulson, MD Laboratorio de Hígado, Páncreas y Motilidad (HIPAM) Departamento de Medicina Experimental Facultad de Medicina-Universidad Nacional Autónoma de México (UNAM) Hospital General de México
	Enrico Corazziari, MD Universitá Sapienza Rome, Italy
	Dan Dumitrascu, MD University of Medicine and Pharmacy Iuliu Hatieganu Cluj-Napoca, Romania
	Carlos Francisconi, MD Associate Professor; Department of Internal Medicine, Faculty of Medicine, Universidade Federal do Rio Grande do Sul. Chief of the Gastroenterology Division, Hospital de Clínicas de Porto Alegre-Brazil
	Shin Fukudo, MD, PhD Department of Behavioral Medicine Tohoku University Graduate School of Medicine
	Ami Sperber, MD Department of Gastroenterology, Tel-Aviv Medical Center. Faculty of Health Sciences, Ben-Gurion University of the Negev-Israel
and the Rome Foundation International Liaison Committee.

Very interesting data about diet and irritable bowel syndrome (IBS) in different parts of the world were presented at the IBS Global Perspective Conference jointly organized by the Rome Foundation and the World Gastroenterology Organisation and at the symposium of the International Foundation for Functional Gastrointestinal Disorders, both of which took place in Milwaukee in April 2011. It has always been known that diet triggers IBS symptoms, but the idea that no matter what people eat, diet is always related to this disorder, is intriguing.

For example, in Asia, IBS patients have more irregular eating habits than individuals without bowel symptoms or even patients with other functional bowel disorders ¹. Studies analyzing the relationship of IBS symptoms ² and sensorimotor responses ³ to meals have provided strong evidence for this. However, analyses of possible associations between food contents and IBS symptoms are scant. Japanese cuisine is comprised primarily of rice, fermented soy bean, vegetables and fish. The Korean diet includes rice, baked beef, and spicy vegetables. Chinese cuisine varies depending on the specific district, but consists mainly of rice, pork, vegetables and sea foods fried with oil. In Southeast Asian countries the diet is based mainly on rice and spicy curry with fruits and meats, while in India wheat or rice, milk, spicy curry and meat are  staples. Although there are no specific items of foods that can be associated with IBS symptoms, capsaicin-rich foods, oily foods, wheat, and alcohol are considered to be aggravating factors. Studies from Japan have shown that, in IBS patients, complete fasting for 10 days induces symptom relief ⁴, as well as improvement in duodenal and colonic motility, visceral perception and mucosal inflammation ⁵.

In Israel, as in other geographical areas and cultural groups, IBS patients are often convinced that their abdominal symptoms are related to food and eating. The Israeli diet is a form of a Mediterranean diet with high amounts of salads and fruits as well as legumes such as chick peas and tahini, and dairy products. These are associated with the prevalence of complaints on bloating and flatulence. In addition, patients often ascribe their symptoms to spicy food. Friday evenings and Saturdays (the Jewish Sabbath) are days in which families gather and enjoy meals together. These are often heavy meals and people tend to overeat. As a result, it is commonplace to hear complaints about abdominal discomfort and aerophagia at the beginning of the week after the Sabbath, although this clinical impression has not been studied formally.

Israelis are avid Internet users. In terms of IBS and food, they are exposed to disinformation, which has led to the adoption of elimination diets, including the recent popularity of gluten-free diets in patients without any evidence of gluten intolerance. Patients often go to practitioners of naturopathy and are given recommendations for very strict diets, in some cases for supposed intestinal Candida infestation. The latter is encountered often by physicians who treat IBS patients (personal communication), but has not been documented in formal research.

Food avoidance is also frequently reported by Italian patients with functional bowel disorders. The widespread use of dairy (mozzarella, ricotta, and cappuccino) and flour-based food (pasta, pizza) in a country with a high prevalence of lactose and gluten intolerance is an inevitable cause of food avoidance. The prevalence of lactose intolerance is 50% in northern Italy, and 70% in southern Italy, and the prevalence of celiac disease in Italy in general is about 7%. However, many other patients avoid lactose or gluten in the erroneous belief that they are intolerant to these food components. Only 75% of patients who claim that they are lactose intolerant have a positive lactose hydrogen breath test ⁶. Many  other patients avoid lactose, gluten-based diets and other types of foods on the basis of unreliable intolerance tests that are popular and  available in the country ⁷.

In central and eastern Europe the diet is traditionally and predominantly based on meat, bread, potatoes, saturated fat and vegetables. In southern areas of Eastern Europe (Greece, Croatia) the Mediterranean diet is common. In former communist countries, including Russia and other ex-USSR states, less antioxidants are consumed in comparison with western countries and the salt  intake is high ^8-9. This dietary  pattern is reflected in high cardiovascular mortality, but with respect to IBS, there are no scientific data that link symptoms to specific foods.  Diarrhea and constipation are aptly attributed  to the type of food consumed, to food intolerances, allergies, etc., but this refers to non-functional conditions such as lactose malabsorption, celiac disease, megacolon, etc. Some patients believe that food may trigger bloating and flatulence. Therefore, patients may also avoid specific food items that they consider responsible for their symptoms, but epidemiological data exist only for functional dyspepsia, not IBS.

In Greek-Orthodox populations, Russians, Romanians, Bulgarians, and Greeks observe the fasting period between Easter and Christmas. Their fasts are stricter than those of Catholics and may involve a totally vegetarian diet for several weeks. However, there are no studies to date that have looked at the effect of fasting on IBS symptoms.

Alcohol consumption in Eastern Europe is heavy, mainly among men. Although spirits with an alcohol content of 40 percent or more, as well as beer and wine, are frequently consumed, patients do not attribute their symptoms to alcohol.

IBS patients in Latin America also associate their symptoms to food ingestion. In México, for example, in a nationwide multicenter study designed to characterize the bowel habit subtypes, patients reported that fatty foods, spicy or highly seasoned foods, and legumes (beans), were most frequently associated with triggering or exacerbating IBS symptoms ¹⁰. No differences in food attributions were associated with bowel habit subtype. In contrast, artificial sweeteners do not appear to be related to symptom generation, in contrast to what has been reported from other parts of the world. Fermentable oligosaccharides (fructans and galactanes), disacharides (lactose), monosacharides (fructose and polyols) (FODMAPs), the highly fermentable and poorly absorbed short chain carbohydrates that have been related to symptoms in  patients with functional gastrointestinal disorders ¹¹, have not been investigated in Latin America. Nevertheless, it is a common observation in clinical practice that patients who chew gum sweetened with fructose and sorbitol report symptom exacerbation, mainly bloating, cramps and diarrhea.

Lately, a blood test for “food intolerance” has become very popular in Mexico. Patients get a list of “foods to which they are intolerant” and follow very strict elimination diets, in accordance with the results. After a period of time they find that there is no improvement in their symptoms and abandon these diets. Celiac disease is very uncommon in Mexico, with a prevalence estimated at less than 1% in the general population so it is not cost-effective to investigate it in patients with IBS ¹². In contrast, in other Latin American countries like Argentina where it is more common, it is worth investigating. Remember that the effectiveness of Cialis (Tadalafil) has been proven by many tests: from the technologically advanced verification standard to empirical researches. For better absorption of it should be taken on an empty stomach as recommended at Mount Sinai Urology CME. It dissolves in the stomach very quickly, almost immediately after the intake. The highest concentration of Cialis in blood plasma is achieved two hours after the drug intake. Also, you don't have to count and monitor the intake of food, as the absorption doesn't depend on the mealtime.

In Brazil, the largest country in the region, the food types most blamed for triggering IBS symptoms, vary by geographical region. For example, palm oil is culturally part of northeastern Brazilian cuisine but is rarely used in the southern states because it is used to cook “heavy” foods. Many of these beliefs have their origin in taboos that have been passed on for generations. Examples of these are that older people cannot eat “heavy” foods, watermelon ingested with wine provokes “indigestion” (meaning severe dyspepsia), fried eggs at dinner are “dangerous” for the health (also implying GI symptoms), and fat, pork and chocolate are “bad for the liver”. It is worth mentioning that many IBS patients complain that everything they eat makes them feel sick to the stomach and they attribute the subsequent “liver malfunction” as the cause of their functional symptoms ¹³.

In conclusion, no matter where you live or what you eat, diet is related to IBS symptoms. It is possible that food intolerance may play a role,  but popular beliefs make a significant contribution to the phenomenon of food avoidance in these patients. Further studies are necessary to  confirm possible associations between foods and IBS in all regions of the world. Optimally, a collaborative multinational study would provide the most interesting and reliable data.

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