A recent internal initiative within CGIAR sets out to "strengthen alignment and accelerate impact in biofortification." SPIA has generated evidence on this topic, and a recent meeting with CGIAR funders suggested real appetite to deploy this evidence in the service of this new initiative. This is the spirit in which ex-post, rigorous evidence is meant to be used: not only as a verdict delivered after the fact, but as an input that informs what comes next.
SPIA’s evidence base on this topic comes from the first wave of country studies (in Bangladesh, Ethiopia, Uganda and Vietnam) and rigorous causal impact studies. From these, a consistent picture of biofortification has emerged: one that does not fit neatly into either a success story or a cautionary tale. It is both.
What's working?
A causal study in Uganda (Macours, Mallia and Okello, 2025) found measurable height-for-age gains in children in households where the parents had been trained to grow orange-fleshed sweet potato and to feed it to them in their first two years of life. This is worth highlighting because the recurrent issue across the CGIAR portfolio isn’t (at least in most cases) whether biofortification can work under certain conditions, but rather when/where those conditions are met and allows farmers and households to benefit.
Mixed results
SPIA’s evidence on the scale at which these conditions are being met is mixed across countries and crops. To cite a few examples: in Uganda, SPIA’s nationally representative survey and DNA fingerprinting found orange-fleshed sweet potato in roughly 3% of sweet-potato-growing households, against modelled projections of 43% adoption.
Given the positive impacts on child nutrition, this is a particularly tough result to take. In Ethiopia, adoption of the same crop sits below 1% and has drifted downward over recent survey rounds. Quality protein maize, bred for higher lysine and tryptophan, turns up in 41% of the sampled maize in Uganda, but only in 1.5% of maize-growing households in Bangladesh, and practically none in Ethiopia. When it comes to zinc-enriched rice, ~2% of DNA-fingerprinted Boro plots in Bangladesh were found to be growing it.
Room for improvement
There are several considerations underneath these reach trends, and each is an area that newer initiatives could build on.
First, reach is often mismeasured. In Uganda, the HarvestPlus projections severely overstated reach. The lesson is not that projections are not important or useful; in fact they remain indispensable where real-time data is scarce. That said, they require periodic validation and ground truthing against ex-post, independent evidence. Deciding when and how to ground truth, at what cost, and at what cadence, is a design question that a new biofortification initiative must tackle.
Second, farmers may not always know they’re growing biofortified varieties. As in the case of Bangladesh, improved seeds are often sold under the names of older, established varieties or outright mislabeled, meaning farmers may unknowingly purchase them. The same pattern appears elsewhere: in Uganda, 34% of farmers with a DNA-confirmed released variety reported what they were growing as “improved” (while the others called it “traditional” or didn't know). This means that if the adoption of biofortified varieties remains invisible, self-reported monitoring will systematically misattribute it.
Third, seed systems play a major role in the reach of biofortified varieties. In Uganda, fewer than a third of bean samples from grain markets (the channel most farmers use) retained a distinct varietal identity, compared with around four-fifths at Quality Declared Seed outlets. In fact, seed quality loss begins almost immediately, revealing a fundamental weakness in the breeding and/or seed multiplication processes. So a farmer trying to buy a biofortified variety may not even receive one. Similarly, in the case of vegetatively propagated crops (like OFSP) the challenge to keep planting material in drought prone areas is yet to be addressed adequately, making farmers often lose their planting material.
Fourth, how farmers perceive and prioritize different traits matters. In Bangladesh, the zinc-enriched wheat variety that has high adoption is also blast-resistant, which is a trait farmers can see and value directly. When a nutritional trait is bundled with other visible traits, adoption could follow more readily. Conversely, as in the case with OFSP in Uganda, consumers disfavor other bundled traits of OFSP (dry matter content in particular) so these questions of taste and texture dominate decision making about which varieties to grow and therefore what household members eat. In addition, it may be hard for households to observe the role OFSP can play in better nutritional outcomes for their children as this plays out over a long period and is influenced by many factors.
None of this argues for or against biofortification. What SPIA evidence points to is a far more nuanced picture which suggests that: a) reach be measured reliably, b) farmer awareness be treated as part of the design rather than an afterthought, c) seed-systems and quality control be strengthened, and d) visible traits that are favored by farmers be bundled with invisible ones for greater adoption.
These are exactly the kinds of priorities a future CGIAR initiative building on existing evidence is well placed to take forward.
Have questions or comments about this article?
Write to spia@cgiar.org. We would welcome the opportunity to engage on this topic further.
