I have been following this discussion with much interest, and would like to request some further clarification because it is critical for all of us to understand this fully.
Carlo, it seems to me that the critical point in your methodology is the second one, whereby you "estimate the proportion of individuals (not only adults) whose average caloric intake over the year falls below their specific caloric requirement".
Could you explain how exactly this is done? This would appear to be a really difficult task given the data availability in various countries..
In India, for example, the National Sample Survey (NSS) data give us estimates of consumption (money spent) on various food categories, from which calorie consumption can be derived at the household level, not for individuals within the household. To get the latter, other assumptions would have to be made, and these are socially and regionally different because of different intra-household patterns of gender and age discrimination across regions, cultural groups and classes. Therefore in India we do not treat the NSS data as a useful source of individual (rather than household) food consumption, and rely instead on other outcome indicators like BMI from other surveys like family health surveys for individual nutrition.
Then there is the further issue of deriving the different calorie requirements specific to occupations. To get this would require using the unit-level data from the NSS data and making further assumptions about likely calorie requirement for different types of occupation as well as hours worked etc. I have had research students who try to do this, it is a Herculean task even for one state within India, much less India as a whole. So I would very much like to know how you derive these estimates for so many developing countries and thereby for the whole world.
Many thanks for sparing the time to educate us on these matters,
All very best regards,
Professor Jayati Ghosh
Jawaharlal Nehru University
New Delhi, India