Baseline characteristics of cases and controls at study enrolment.

<p>NA; not applicable.</p><p>CD, Crohn's disease; IQR, interquartile range.</p><p>*Civil marriage or living with a partner.</p>†<p>Missing data for 3 cases and 2 controls.</p>‡<p>At least some tertiary education.</p><p>Baseline characteristics of cases and controls at study enrolment.</p

Environmental risk factors over three age intervals; 0–5 years, 6–10 years and 11–18 years.

<p>*OR odds ratio adjusted for age at study enrolment, ethnicity and gender, and 95% confidence interval. Subjects who responded ‘do not know’ were excluded from analysis.</p><p>Environmental risk factors over three age intervals; 0–5 years, 6–10 years and 11–18 years.</p

Patient Medical and Surgical Management and Extraintestinal Manifestations (EIMs).

<p>*Statistical analysis excludes black patients.</p>†<p>Excludes 15 patients with insufficient records of medical management.</p>‡<p>Excludes 12 patients with incomplete records of surgical dates.</p>§<p>Other EIM disorders included; ankylosing spondylitis and primary biliary cirrhosis.</p

Montreal Classification Scheme.

<p>*Upper gastrointestinal (GI) modifier (L4) can be added to L1–L3 when concomitant upper GI disease present.</p>†<p>B1 category should be considered “interim” until a pre-specified time has elapsed from time of diagnosis. Suggested time period is between 5–10 years.</p>‡<p>“p” is added to B1–B3 when concomitant perianal disease is present.</p

Environmental exposures during infancy.

<p>*Subjects who responded ‘do not know’ were excluded from analysis.</p>†<p>Adjusted for age at study enrolment, gender and ethnicity. The odds ratio in the above table was obtained from the logistic regression models, where the environment risk factors were modeled by case/control group.</p><p>Environmental exposures during infancy.</p

Demographic and Baseline Characteristics of Patients.

<p>IQR, interquartile range; IBD, inflammatory bowel disease.</p><p>*Statistical analysis excluding black subjects. No subjects reported being of Indian or Asian ethnicity.</p>†<p>Age at study enrolment missing for 1 Cape Coloured subject.</p>‡<p>Civil marriage or living with a partner.</p>§<p>At least some tertiary education.</p>a<p>Smoking status at diagnosis; data missing for 5 subjects. Smoking status at study enrolment; data missing for 7 subjects.</p>b<p>Family history IBD defined as parents, siblings or offspring.</p

Patient Phenotype According to Montreal Classification Scheme.

<p>*Statistical analysis excludes black patients.</p>†<p>Adjusted for gender, smoking and duration of symptom onset.</p>‡<p>Adjusted for gender, smoking, age of onset and duration of symptom onset.</p>§<p>Adjusted for gender, smoking, disease duration and age of onset (as appropriate).</p>a<p>Age at study enrolment; data missing for 1 Cape Coloured subject.</p>b<p>Disease location was not confirmed by upper endoscopy, ileocolonoscopy or small bowel imaging for 2 Cape Coloured subject at diagnosis and 1 Cape Coloured subject at study enrolment. Overall, no subjects had upper gastrointestinal disease</p>c<p>“p” is the perianal modifier added to B1–B3 when concomitant perianal disease is present.</p

Volume of sales of select leading categories of packaged foods, 2010, and rate of increase 2005–10.

<p>Source: Euromonitor 2011 <a href="http://www.plosmedicine.org/article/info:doi/10.1371/journal.pmed.1001253#pmed.1001253-Euromonitor1" target="_blank">[17]</a>.</p>*<p>in thousand tonnes, except for ice cream, which is million litres.</p

Hypothesized link between Big Food and the consumer food environment.

<p>Hypothesized link between Big Food and the consumer food environment.</p