The Nutri-Trend-Study 2000 conducted by Nestlé Suisse SA and supported by the Swiss Federal Office of Public Health collected data on body weight and height of a random sample (n = 1004) of persons aged 18-54 years living in Switzerland. 3% of participants are underweight (BMI < 18.5 kg/m2), 26% overweight (BMI 25-29.9 kg/m2), 5% obese (BMI > or = 30 kg/m2) and 66% are of normal weight (BMI 18.5-24.9 kg/m2). Nutritional knowledge and attitudes of the BMI-groups do not differ substantially. All groups but especially participants with a BMI of 25+ should be better informed about the health consequences of an unbalanced diet. Furthermore they should be encouraged to adopt a physically active lifestyle and a healthy diet to remain within the BMI-range of normal weight or to reduce overweight.