Dr. Giacomo Zanello, University of Reading, holder of an IMMANA Grant on Developing Methods to Improve Nutrition Assessment by Measuring Energy Expenditure
Can wearable activity devices shed light on nutritional requirements of the poor?
Wearable devices and activity bracelets have become popular electronic gadgets for gym-goers and people pursuing a healthy and active lifestyle. Our research shifts the paradigm around the technology embedded in these gadgets. Can wearable devices be used to better assess the nutritional requirements of farm households living in low and middle income countries where undernutrition prevails?
Our recently awarded IMMANA grant will build and expand on a recently published article in Development Engineering that aims to develop assessment methods taking advantage of new accelerometry-based technologies.
Benefits of accelerometry devices
Scaled-up empirical measurement is possible thanks to recent advances in these rugged devices that are suitable for use in the context of rural and agricultural occupations. Worn by respondents in the waist area throughout the day, these devices facilitate non-intrusive data collection and do not require users’ input. They record high frequency data on the intensity of movements, which can be converted into calorie expenditures. Such technology enables us to scale up empirical measurement of energy expenditure in rural populations that cannot be achieved with conventional methods.
Measurement of energy expenditure required for agricultural and livelihood activities, with accelerometry devices, can be used together with food intakes data to assess the prevalence, depth and severity of undernutrition in rural areas in developing countries. It can also shed light on intra-household gender-differentiated labour allocation and energy expenditure patterns associated with interventions aimed at increasing agricultural productivity (e.g. adoption of new agricultural technologies or practices). Finally, they can provide an empirical assessment of the link between agricultural development interventions and nutrition outcomes for different members of rural households.
New insights into energy expenditure of rural households in Ghana
The published paper reports on the protocols adopted and the findings from a pilot study in northern Ghana involving 40 respondents wearing accelerometry devices for a week. We show how integrating energy expenditure data from wearable accelerometry devices with data on activity and time-use can provide a window into agricultural and rural livelihoods in developing country contexts that has not been previously available for empirical research. The method adopted allows for a robust and precise assessment of gender-differentiated intra-household allocation of labour in rural households.
Our findings confirm some of the anecdotal facts about agricultural and rural livelihoods, but the study also provides several new insights. While the overall daily energy expenditure for men is greater than for women, we find that women consistently maintain higher physical activity levels than men through the course of the day. Men and women spend a similar proportion of their time on economic activities – the greater proportion of time that women spend on domestic activities appears to involve a trade-off against opportunities for social interactions. Agricultural and rural livelihoods are dominated by “light” and “moderate” activities rather than by “vigorous” activities. Daily energy expenditure for both men and women is substantially lower than the norm (2,900 kcal per day) used for computation of the poverty line in Ghana. While the sample in our study is not representative of rural Ghana, the results suggest that any assessment of poverty based on a normative calorie requirement of 2,900 kcal per adult equivalent per day may overstate the incidence of poverty or calorie deficits among the rural poor in Ghana.
Our IMMANA project – measuring the gap between energy intake and expenditure to inform policies and programmes
The ongoing IMMANA scale-up project is undertaken in collaboration with Tufts University, USA, the National Institute of Rural Development and Panchayati Raj in India, and with the University for Development Studies in Ghana. It brings together interdisciplinary expertise in food economics, nutrition and agricultural and rural development and experience in survey design and data collection in developing country contexts.
This new study will scale up the experience we gained with the pilots and will follow farm households in India, Nepal and Ghana across the whole agricultural season - from land preparation to harvest – and across different agricultural systems.
Our aim is to determine the extent of any gap between energy intake and expenditure to better inform policies and programmes designed to address undernutrition. The applications of the methodology developed through this research will facilitate a better understanding of multiple nutritional issues of almost 800 million people currently estimated as food insecure.