A Combined Healthy Lifestyle Index in Assessing the Relationship with Irritable Bowel Syndrome: Better Prediction of the Disorder

Irritable Bowel Syndrome (IBS) is one of the most common gastrointestinal disorders worldwide. Symptoms of IBS include chronic or recurrent abdominal pain or discomfort associated with abnormal bowel habit [1]. IBS was prevalent approximately in 10-15% of different population groups and was found predominantly in women [2]. Several important factors are involved in etiology of IBS including disrupted gut microbiota function, immunological dysfunction, food intolerance, altered gut motility, psychological distress factors and genetic predisposition. Several investigations have evaluated the relationship between lifestyle-related factors and IBS. Numerous modifiable risk factors, including poor dietary intakes, physical inactivity, smoking, having high level of distress and obesity, have been studied in association with the disorder; however, findings were conflicting. For example, in an internet survey of general population in Japan, positive relationships were found between physical inactivity, insufficient sleep, meals irregularly, insufficient intake of vegetable and meat and being highly susceptible to stress, as independent predictors, with IBS symptoms [3]. However, smoking -as a risk factor for IBS- was not taken into account in that study. Another survey has also documented that children with IBS were susceptible to stress and had impaired sleep and eating habits [4]. In Lebanese adults, being water pipe smoker and alcohol consumer were associated with a higher prevalence of IBS; while cigarettes smoking, and physical exercise were not significantly associated with IBS occurrence [5]. Individuals with IBS in London habitually had more intake of sodium and low intake of fiber, selenium and iodine, as well as having low scores for diet quality [6]. However, a cross-sectional study among IBS patients in the United Kingdom showed that the balance of energy macronutrients was favorable, intakes of selected micronutrients significantly exceeded the reference nutrient intakes [7]. Another investigation in Sweden found the same results in IBS patients compared with control group from a nation-wide dietary survey [8]. Most of these studies have focused on the relation of a certain