This paper studies a topic in the triangle of environment, development and health—the effectiveness of the improved cooking solution. While a range of improved cook-stoves (ICS) is available in the market, since decades with a number of new entrants from recent years, adoption is still low in many developing regions, such as sub-Saharan Africa, also because stove performance is sometimes found to be deficient. However, in Nigeria, Africa’s most populous country, few improved cook-stove interventions are on-going. Incidentally, there is little evidence on the effect of improved cook-stoves on different components of health and environmental outcomes in rural Nigeria. This study, using cross-sectional data from Cross River State, the State with the largest forest area in the country, analyzed the impacts of locally designed improved cook-stoves on the environmental and health outcomes of rural women. A sample of four hundred (400) married women was drawn from eight rural communities with the highest concentration of improved cook-stove users. The woman in-charge of cooking in each household was the respondent. Also, in each household, the household head (if different from the primary cook) was interviewed. Using inverse propensity score weighting for data analysis, we found significant fuel and time savings from the adoption of the cook-stove. However, this study found no evidence of the reduction of indoor air pollution associated diseases given stove design and users’ behavior. This underscores the need to revisit the design of the stove and consider users’ cooking behavior in the design.