Smoking and sugar intake are separate but interactive risk factors in Crohn's disease.

Abstract

SUMMARY Previous studies have consistently found strong positive associations between refined sugar intake and Crohn's disease (CD) and recently between smoking and CD. As refined sugar intake and smoking are themselves associated we have enquired about smoking and added sugar intake (AS) and smoking in CD using a postal questionnaire sent to 104 CD patients and 153 community controls. Smoking and AS were associated with one another. After adjusting for AS, smoking showed a significant association with CD with a relative risk of 1.8. After adjusting for smoking habit, AS was also strongly associated with CD in never and exsmokers and in a dose response pattern, with the relative risks for no AS, <50 g/day and >50 g/day being respectively 1.0, 1.8, and 4-6 (X2=12-1; p<0005). No association between CD and AS was evident in smokers. The AS relationship was supported by a separate association between frequency of confectionery consutnption and CD. These findings indicate that while smoking and AS are individually associated with CD combined exposure results in no further increase in risk, suggesting that they may operate through a common mechanism. Increased refined sugar consumption by patients withCrohn's disease (CD) was first reported by Martini and Brandes in 1976 and has since been demonstrated in many studies, although some have suggested that the increased consumption is secondary to the development of CD.'-9 We, and subsequently others, have recently found a strong association between smoking and CD which antedates disease onset."''5 Smoking has previously been found to be positively associated with sugar consumption.'6`7 It therefore seemed possible that the association of smoking or sugar consumption with CD might be due to confounding, that is, any increase in smoking, or sugar consumption, in CD patients might be accounted for by the one habit being associated with the other. We have therefore reapproached subjects from our earlier study with a second questionnaire designed to determine whether the association of smoking and CD was related to increased sugar consumption by smokers with CD.

The effects of vitamin A on cells of innate immunity in vitro

“…Although more risk factors are expected to follow (Barrett et al, 2008;Latella et al, 2010;Nguyen et al, 2006), the role of many these in the pathophysiology of CD, for example, is unclear (Mathew, 2008) and, nevertheless, account for only a fraction of observed CD incidence (Torkamani et al, 2008). Key environmental triggers include dietary factors, food additives or drugs (Cosnes, 2010;Hou et al, 2011a,b;Järnerot et al, 1983;Katschinski et al, 1988;Martini and Brandes, 1976;Silkoff et al, 1980;Thornton et al, 1979), and cigarette smoking (Avidan et al, 2005;Cosnes et al, 2001Cosnes et al, , 1996Kane et al, 2005) while psychological factors may influence disease course (Cámara et al, 2010;Danese et al, 2004;Levenstein, 2002). Significantly, the innate immune system and epithelial barrier function are critical to the pathophysiology of both UC and CD; thus, environmental triggers that influence the intestinal microbiota and modify intestinal barrier function would appear particularly relevant.…”

A review of associations between Crohn’s disease and consumption of sugars

“…Mayberry et al (1980) and Graham et al (1978) used the amount of sugar added to beverages and cereals as a proxy measure of sugar consumption, while a combination of added sugar and frequency of sugar-containing foods was used by Silkoff et al (1980), Mayberry et al (1981) and Penny et al (1983). Katschinski et al (1988) used a combination of added sugar and confectionery consumption. It is doubtful whether these types of methods offer an accurate re¯ection of daily sugar intakes.…”

“…However, there are no details in this short report regarding disease activity, diet methodology, ®gures for sugar intake or re®ned carbohydrate intake. Katschinski et al (1988) used a postal questionnaire to enquire about smoking habits, added sugar intake and confectionery consumption in patients with CD and matched controls from a General Practitioner's list. Sugar intake was not quanti®ed but expressed in 40 g increments.…”

“…Interestingly, despite the patients' claims that sugar intakes had not changed since the onset of symptoms, current intakes of sugars were found to be lower than the intakes recalled for the period before symptoms appeared. Katschinski et al (1988) examined diet as part of a study looking at the relationships between smoking and CD in 104 patients matched with 153 age-and sex-matched controls. The postal questionnaire attempted to quantify intakes of confectionery and sugar added to drinks and cereals.…”

Interaction between Susceptibility and Environment: Examples from the Digestive Tract

“…However, most studies dealing with this subject have only provided indirect evidence of a possible cause-and-effect relationship between specific dietary factors and IBD [69,70,71,72,73]. Fast food has also been reported to increase the risk of CD and UC [74].…”