In order to define the effectiveness of interventions addressed to poverty reduction and the degree of effect that the economic determinants have in the nutrition in rural and poor areas of low-resource countries, we performed a revision based on publications indexed to Medline (accessed by PUBMED) and the Cochrane Library (CL) up to year 2005. We chose the studies about interventions/programmes of family economic improvement that have as objective to reduce the malnutrition and those addressing malnutrition determinants. The methodological quality of the researches was evaluated according to the criteria and classification of the CL, and we selected three articles about effectiveness of economic interventions in the malnutrition and eleven articles about economic determinants of malnutrition. We found that the upgrading of the family income can improve the malnutrition while enhancing the acquisitive power of the homes and the number of calories taken, especially amongst the poorest. Nevertheless, the production and availability of the food, the distribution of the expenses inside the homes, the environmental sanitation, inequity, the educational level and the lack of time of the mother, the distribution of provisions inside the houses and the urbanization, among others, influence the nutritional status, allowing overestimation or subestimation of the impact of the family outcomes in the nutrition.