The prevalence of undernourishment in India – the percent of people consuming insufficient calories to meet their energy requirements – has been rising steadily since the mid-1980s. Paradoxically, this period has been one of robust poverty reduction and rapid economic growth. The reasons for the apparent reductions in calorie consumption underlying increased undernourishment have been the subject of intense debate both within India and internationally. This paper critically reviews this debate, finding that is has taken place outside of the context of India’s recent nutrition and epidemiological transitions, which appear to have brought with them increased, not decreased, food consumption. The debate has also taken place under the unchallenged assumption that the data on which the conflicting trends are based, collected as part of the country’s Household Consumption and Expenditure Surveys (HCESs), are reliable. The paper provides supporting literature and empirical evidence that one key factor driving the measured calorie decline is incomplete collection of data on food consumed away from peoples’ homes, which is widespread and rapidly increasing. The India example shows that complete measurement of this food source in the HCESs of all countries is vital for accurate measurement of undernourishment and, indeed, poverty at national, regional and global levels.