Stunting reduction in Peru

Food security / migration from higher to lower altitudes
Overall impact: Strong

Impact: 

Positive

Strength: 

Strong

Improved access to food is associated with living at lower (and less remote) altitudes. In Peru, the average household surveyed in the 2016 DHS was located at a substantially lower elevation than the average household surveyed in the 2007/2008 DHS.

Literature Review

Impact: 

Positive

Strength:

Strong

Existing evidence linking food security/improved consumption to child growth is abundant in Peru. Food availability was linked to changes in HAZ in a longitudinal study conducted in urban Peru, and several other studies noted higher household food consumption and expenditure being strongly associated with height gain in children between 1 and 5 years.        

Another study reported that households that were chronically food insecure had children with significantly lower HAZ and poor diet diversity compared to households that were food secure, even after adjusting for co-variables such as age, sex, and socioeconomic status. Animal protein consumption has been associated with household food security and better overall dietary diversity, and improved anthropometry in Peruvian children.       Sobrino, et al. found that residence above 500 meters was a risk factor for stunting in Peru.

Quantitative Analysis

Impact: 

Positive

Strength:

Strong

Unable to analyze using linear mixed effects regression method due to the lack of an appropriate ecological variable.

Using change in elevation (presumably driven by migration) as a proxy variable, the Oaxaca-Blinder decomposition analysis found that food security stood out as a significant predictor of HAZ across age groups and time periods (with the exception of the under-five age group during the 2008-2016 time period).

Qualitative Analysis

Food security was not specifically mentioned (migration was also not mentioned).

Conclusion

In our study, the downward migration of populations from higher altitude communities in the Andes to lower altitude communities from 2007 to 2016 were an important part of child HAZ improvement in Peru. We postulate that this is reflective of better access to more and diverse food.

At the same time, the availability of food increased across Peru. The amount of harvested cereal grains increased from 683,214 tons to 1,236,782 tons in Peru from 1990 to 2016, and the per capita availability of food increased from 1999 - 2016. Over a similar time period, the protein supply increased from 63 - 73 g/capita/day and the availability of animal protein increased from 21 g to 27 g/capita/day. Data from the FAO depicts a decrease in food deficit, and an increase in energy supply adequacy of 52 kcal/capita/day and 121 percent in 2016, respectively. Though speculative, these changes in energy available and overall diet quality may be associated with better overall nutritional status among women and children in Peru.