Objective: To assess the association between nutrition and health in an adult urban homeless population. Design: Cross-sectional ± nutritional state (body mass index (BMI), triceps skinfold (TSF), upper arm circumference), dietary habits (food frequency), socio-demographic data and self-stated diseases were assessed. Setting: Four sites for homeless people in Kiel and Hamburg, Germany. Subjects: Sample of 75 homeless people (60 males, 15 females) aged 19±62 years. Results: A lack of food was not found in the majority of the homeless. Seventy-six per cent of the study population showed a normal dietary pattern. Critical food groups were fresh fruit and vegetables, rice and noodles. However, 52 or 29% of the homeless were malnourished (i.e. they were below the 25th or 5th percentile of arm muscle area). In addition, 22.7% of the homeless were obese (i.e. BMI>30 kg m 22 and/or TSF>90th percentile). Almost two-thirds of the population suffered from at least one chronic disease (prevalence of nutrition-related disorders 33.3%, gastrointestinal disorders 32.0%, dental diseases 22.7%, psychiatric disorders 18.7%, wasting diseases 6.7%). Smoking (prevalence rate 82%), drinking alcohol (51%) and drug abuse (20%) were frequent among homeless people. Food intake was not related to nutritional state, the prevalence of chronic diseases or addiction habits. By contrast, a poor nutritional state was associated with drug abuse and the prevalence of wasting diseases. Conclusion: Prevention of nutritional problems should be directed to health-related problems such as the prevention or treatment of chronic diseases and addiction habits.