This study assesses the impact of a nutritional intervention aimed at reducing childhood overweight in German preschoolers.

Objective: To assess the impact of a nutritional intervention aimed at reducing childhood overweight in German preschoolers.

Design: Using a cluster-randomized study design with waiting-list controls, we test a six-month intervention administered once weekly by a nutritional expert consisting of joint meal preparation and activities for children and parents like tasting and preparing nutritious, fresh foods. At baseline, six and twelve months, a parent-completed questionnaire assesses fruit and vegetable intake (primary outcomes) and water and sugared drink consumption (other outcomes). Direct measurement assessed BMI, percentage body fat (skin fold thicknesses) and waist-to-height-ratio. An intention-to-treat analysis used random effects panel regression models to assess the intervention effect, adjusted for each child's age, gender, immigrant background and maternal education.

Setting: 18 Preschools from three south German regions. Subjects: Healthy children from three to seven years of age.

Inclusion Criteria:

• Pre-schools were eligible to participate in the study if they were located in one of three predefined regions and had applied to participate in the nutritional intervention module of a state-sponsored health promotion programme 'Komm mit in das gesunde Boot' ('Come aboard the health boat'), with at least fifteen children participating.
• Healthy children in eligible preschools

Exclusion Criteria:

• Age under 3 years or above 7 years
• Serious health problems
• Genetic conditions
• Metabolic diseases
• Acute infectious diseases