Re. the link between smallholders' participation in export markets and food security.
To the broader question: there is strong evidence that the removal of trade barriers leads to improved food security—particularly through the prevention of food price spikes. (See, for example, Kym Anderson and Johan Swinnen’s presentation on “How can trade improve food security in sub-Saharan Africa?” at http://fsi.stanford.edu/multimedia/how-can-trade-improve-food-security-sub-saharan-africa-0 or my own paper, “Feed the Future Learning Agenda Literature Review: Expanded Markets, Value Chains and Increased Investment” at http://agrilinks.org/library/feed-future-learning-agenda-literature-review-expanded-markets-value-chains-and-increased).
There is also evidence that smallholder market participation in general is key to poverty reduction. (See, for example, “Smallholder market participation: Concepts and evidence from eastern and southern Africa” by Christopher Barrett.) The impacts on smallholder farmers of engaging in export agriculture of course depend on the specific market structures and integration mechanisms. Ashraf, Giné and Karlan provide a cautionary tale of depending on a single buyer in “Finding Missing Markets (and a Disturbing Epilogue): Evidence from an Export Crop Adoption and Marketing Intervention in Kenya.”
But well-structured export development initiatives, that strengthen multiple market channels and ensure an equitable sharing of risk, can substantially increase incomes, which can be invested in ways that strengthen food security. ACDI/VOCA’s projects in support of smallholder production of specialty coffee in Ethiopia, birds eye chilies in Malawi, and cocoa in Vietnam—to name but a few—have allowed small-scale farmers to increase their incomes, accumulate assets, and diversify their livelihoods to increase their household food security.
Data on impact on diet seems to be much harder to find. It is an area that we at ACDI/VOCA are investing in now—and we would love to hear from others who have measured nutritional improvements as a result of incomes increases. We know, of course, that even when dietary diversity increases, the inclusion of unhealthy food groups means that this does not necessarily improve nutrition. And we all know anecdotally that incomes alone don’t lead to nutritional gains, but that nutritional education, improved sanitation, health services, etc., are also required. So smallholders’ inclusion in market-oriented production can be part—but will not be all—of the solution to food security.