After periods of progress, prevalence of undernutrition has been increasing in many low- and middle-income countries (LMICs) since 2015. At the same time, with an increase of obesity rates a second burden has been imposed on people living in LMICs. Many common drivers of both forms of malnutrition led to a double-duty call for action to fight undernutrition and obesity simultaneously and with combined resources. The joint effort is of utmost importance, more than ever in light of increasing food insecurity and poverty caused by the COVID pandemic. However, studies of the growing body of obesity interventions have not thoroughly incorporated an impact evaluation of undernutrition, and a comprehensive literature review is missing. To systematically review obesity interventions in LMICs, main relevant databases have been used. We found that deliberate attention to undernutrition is yet rare which calls for a continuous emphasis of the double-duty focus shift.