Dietary fibers including resistent starch, RS, and arabinoxylans, AX, have been shown to have anti-inflammatory effects and to change the composition of the faecal micro flora in the colon.

In this unblinded dietary intervention cross-over study 20 subjects with metabolic syndrome are randomized to two types of diet intervention: a low and a high fiber diet. The participants are subjected to endoscopy before and in the end of each intervention.

Dietary fibers including resistent starch, RS, and arabinoxylans, AX, have been shown to have anti-inflammatory effects and to change the composition of the faecal micro flora in the colon.

In this unblinded dietary intervention cross-over study 20 subjects with metabolic syndrome are subjected to two types of diet intervention:

1. a western style diet, WSD, with a low fiber content and
2. a healthy carbohydrate diet, HCD, a high fiber diet. Between the two 4-weeks diet is a wash-out period of four to eight weeks. The participants are subjected to endoscopy with tissue samples before and in the end of each intervention. Fecal and blood samples will be collected at the same time.

We hypothesize that a high content of resistent starch and arabinoxylans increases colonic butyrate concentration, changes colon's mucosal immune system and the microbiota.

A small pilot study will be carried out on 12 healthy volunteers in order to obtain a reference to participants with metabolic syndrome. The healthy volunteers will be subjected to an endoscopy but no dietary intervention.

Inclusion Criteria: At least 3 out of 5 following criteria:

• Central obesity (Female > 80 cm, Male > 94 cm)
• HDL cholesterol (Female < 1,03 mmol/L, Male < 1,29 mmol/L)
• Bloodpressure (> 130/85 mmHg)
• Fasting Blood Glucose > 5,6 mmol/L

Exclusion Criteria:

• Diabetes
• Gastrointestinal disease
• Serious liver, heart or kidney disease
• Anticoagulation treatment
• Anaemia
• Corticosteroid treatment
• Waist circumference above 130 cm
• Alcohol or drug addiction
• Pregnancy or lactation