índice de Paridad Poder de Compra Nutricional: comparación de los precios calóricos entre dietas habituales y saludables

objective: develop the index of nutritional purchasing power parity (nut3-cio) as an instrument to compare the caloric costs of a healthy versus an unhealthy diet between regions or cities in a country over time. methods: indices of caloric prices were constructed and the "law of one price" was used to derive the nut3-cio index. caloric inflation rates were obtained using basic descriptive statistics. the nut3-cio was applied in the major cities of mexico during the period from january 1996 to december 2010. results: the statistical behavior of the nut3-cio revealed that, in mexican cities, products for a typical diet are less expensive than products for a healthy diet. the findings showed a cyclical behavior to the index, a high correlation between inflation for the typical diet and inflation for the market basket, and a high persistence of prices. conclusions: the nut3-cio index makes it possible to periodically compare the price differential of two types of diets-typical and healthy-between cities in a single country. this instrument could help health authorities identify the cities where it is easier or more difficult for consumers to access a typical or healthy diet in terms of cost. furthermore, it makes it possible to estimate the percentage adjustment necessary in each city to attain levels of nutritional purchasing power parity.