Malnutrition is unhealthy: obesity, type 2 diabetes, cardiovascular diseases, some cancers, and premature mortality are reliably associated with poor nutrition. However, literature reveals that some population groups are at higher risk of poor nutrition than others. More specifically, evidence shows that people with low social status are more likely to have poor nutrition than those with higher status, what may contribute to health inequalities. In this article, selected reviews and meta-analyses on social inequalities in nutrition are presented. By showing current data from the Second National Food Consumption Study, the situation in Germany is highlighted. Further, potential causes of social inequalities in nutrition are discussed, drawing on the results of current research. More specifically, socioeconomic and structural deprivation (e.g., poverty, living in deprived neighborhoods) in addition to unfavorable psychosocial (e.g., poor knowledge of nutrition, low levels of social support) and sociocultural factors (e.g., unfavorable nutritional traditions) might be associated with poor nutrition in people with low social status. Interventions promoting nutritional quality in disadvantaged groups should take into account the various influences on nutrition and meet good practice criteria for health promotion. Using three examples of interventions, conceivable concrete measures that can reduce social inequalities in nutrition are presented.