The Cost of the Diet is predominantly used as a general advocacy tool to inform discussions about food, dietary diversity, nutrition and livelihoods.
As the software can calculate the cost of a nutritious diet for up to 6 seasons, the results can offer a unique perspective on seasonal changes in the price and availability of foods, identifying periods where households may be vulnerable to high food prices which affect their ability to afford a nutritious diet. This offers an insight for nutrition and health programme developers to assess when nutrition and food security interventions may have the greatest impact.
The foods selected by the software can also help to understand which nutrients are the hardest to obtain from locally available foods. The software can identify the foods which are the least expensive sources of energy and nutrients. This information could be used to design nutrition and food security interventions aimed at improving the nutrient quality of the diet, promoting the least expensive sources of nutrients or increasing the availability of the currently expensive food groups, which in turn, could reduce their market price.
For example, in Burera district, Rwanda, avocado was identified as a cheap but rich source of energy, fat, vitamin C, soluble B group vitamins, folic acid and copper whilst yoghurt was identified as the cheapest source of vitamin B12, meeting 96% of total needs for the family and calcium providing 80% of the total need for the family.
Estimating the affordability of the diets by wealth group using income and expenditure data from the Household Economy Analysis can be used to identify the wealth groups most at risk of insufficient economic access to a nutritious diet and therefore most at need of food security or nutrition interventions.
This vital information on the affordability of the diet can also be used to estimate the size of cash transfers for social protection programmes intending to have an impact on nutrition. For example, a Cost of the Diet analysis in Lindi district, Tanzania, found that families in the poorest wealth group could not afford a nutritious diet, estimating that 115% of their total income would need to be spent to meet their energy and nutrient requirements.
One of the most innovative aspects of the cost of the diet software is that potential interventions can be modelled to estimate their impact on improving the quality and the affordability of the diet. These results can be used to inform and influence policies and programmes in both nutrition and food security and can contribute to both advocacy processes and debates at local, national and global levels.
For example, a Cost of the Diet analysis in Pakistan found that iron and zinc requirements could not be met by local foods for a 9-11 month old child. The impact of giving this child a sachet of micronutrient sprinkles twice a year for 30 days, six months apart on the quality of the diet was modelled. The software estimated that all the nutrient requirements for the child could be met and the cost of the diet could be reduced by 60% as a result of this intervention.
Regular cost of diet assessments in an area could also be used help understand changes in food and nutrition insecurity in a particular context and therefore act as an early warning indicator within food security and nutrition early warning systems.
A cost of diet analysis is most useful when chronic undernutrition and micronutrient deficiencies have been identified as nutritional problems and when the availability or affordability of nutritious foods are likely to be among the underlying causes.