Development of low-cost sample diets for adults living in rural areas of Lebanon using linear programming models -

Abstract

Food price is a main factor affecting food choices, and hence has a major impact on health, particularly in markets where nutrient-dense healthy foods are more expensive than energy dense nutrient-poor foods. Subsequently, the question of how much a nutritious diet costs is of concern, especially among low-income individuals. In Lebanon, diet quality can be jeopardized in the food insecure, even in those living in rural areas. Linear Programming (LP) is a mathematical technique that has been used in the field of nutrition to design nutritious yet affordable diets and to identify the impact of cost constraints on diet quality and diversity. The aim of this study was to use a Linear Programming approach to develop a food basket for men and women, 19-50 years of age, living in rural areas of Lebanon. An LP model was designed on MS Excel 2010, based on data from previous research conducted among rural Lebanese populations. The model included prices of food items and of composite Lebanese dishes, as well as their nutritional composition per 100 grams. The model was run for two main objective functions; (1) to meet energy needs and (2) to minimize energy intake; while respecting a set of consumption constraints and cost constraints in order to attain a balanced, affordable and culturally acceptable diet. Results showed that using a rural Lebanese food list, it is possible to attain an affordable and healthy food basket while respecting cultural habits. However, when a very low cost diet was modeled, the resulting food quantities obtained were illogical. The current study is in agreement with previous research highlighting the importance of consumption constraints during LP modeling. In addition, it showed that using the rural Lebanese diet as a basis for consumption norms, there was an association between food prices and diet quality. In fact, the addition of the cost constraint increased the caloric contribution of refined grains and solid fats and added sugar to the diet.