(Cost-)Effectiveness of SLIMMER Diabetes Prevention Intervention

Inclusion Criteria: * Age 40-70 years * Impaired fasting glucose (IFG; i.e. venous plasma glucose concentration ≥6.1 and ≤6.9 mmol/l) during the past 5 years, according to the GP registration database OR diabetes risk score ≥7 as calculated from the Diabetes Risk Test * Willing and able to participate in the intervention for at least 1.5 years * Dutch speaking Exclusion Criteria: * Known diabetes mellitus * Any chronic illness that makes 1.5-years survival improbable, interferes with glucose tolerance, or makes participation in a lifestyle intervention impossible * Patients with any severe cardiovascular disease (this also includes history of cardiac dysrhythmia), unless GP gives agreement * Medication known to interfere with glucose tolerance * Any mental or physical disability that will hinder participation in the lifestyle intervention * Severe psychiatric disease * Patients who showed bad compliance in the past * Participation in another regular vigorous exercise and/or diet programme, i.e.: * Intensive exercise programme: any exercise programme offered by a physiotherapist and/or patients sporting at least 3 times a week at their own initiative. * Intensive diet programme: patients who visited a dietician at least 3 times during the last year.