Note: This page summarizes the rationale behind a GiveWell grant to Semilla Nueva as of June 2025, when we made the grant. Semilla Nueva staff reviewed this page prior to publication.
In a nutshell
In June 2025, GiveWell recommended a $175,212 grant to Semilla Nueva to complete a study testing whether their biofortified maize increases iron absorption in school-aged children. Semilla Nueva had funding from USAID's Development Innovation Ventures (DIV) to conduct this study, but that grant was terminated, leaving a funding gap for critical sample analysis and publication activities.
We are recommending this grant because:
- We think biofortification could be a promising intervention for addressing micronutrient deficiencies. What we learn from this study could inform future investigations of biofortification as a potential approach for addressing iron deficiency in Sub-Saharan Africa, where fortification and supplementation may face operational challenges.
- We estimate Semilla Nueva's biofortification program is currently 3-8 times as cost-effective as cash transfers, but our estimate could increase in the future if costs decrease and additional iron benefits are incorporated into our analysis.
- This grant leverages a significant prior investment at a time-sensitive moment. The study samples have already been collected using $260,000 in previous funding from Development Innovation Ventures, a USAID program. However, funding for this program was recently cut, and the samples may degrade if not analyzed by June 2025, making this a time-sensitive funding opportunity.
Our main reservations about this grant are:
- We conducted limited due diligence due to time pressure. The risk of sample degradation meant we had to make this funding decision quickly, without time to review the study protocol in detail or triangulate key claims about the study's broader value.
- We do not have a complete cost-effectiveness analysis for biofortification. We lack a full cost-effectiveness model and estimate of room for more funding for biofortification programs. We also have not analyzed whether maize consumption patterns align with iron deficiency prevalence in geographies where we think biofortification could be well suited to addressing iron deficiency anemia.
Published: September 2025
The organization
Semilla Nueva scales biofortified maize with enhanced zinc, iron, and protein content in Central America and Eastern Africa.1 The organization primarily works in Guatemala but has begun expanding to Eastern Africa through partnerships with One Acre Fund to replace existing seeds with biofortified varieties.2 Semilla Nueva is also exploring additional work in Africa, including collaborations with seed suppliers.3
The intervention
Biofortification involves breeding or genetically modifying crops to have better micronutrient content.4 Semilla Nueva's biofortified maize contains enhanced levels of zinc, iron, and protein. It expects that the biofortified maize should also increase iron absorption.5 This is because the biofortified maize has more iron than unfortified maize and a similar level of phytic acid (the latter reduces iron absorption, so maintaining similar levels while increasing iron content could improve iron uptake).6
The study
This $175,212 grant will fund completion of a study to determine whether Semilla Nueva's biofortified maize increases iron absorption in school-aged children compared to conventional maize.7 The study was originally funded by USAID's Development Innovation Ventures (DIV), but that grant was terminated, creating a funding gap.8 The experiment has already been run - participants were found and randomized, fed with different maize types, and blood samples have already been collected from study participants, but funding is needed to complete sample analysis, data analysis, and publication of results.9
The study aims to measure how much zinc and iron children absorb from biofortified maize compared to conventional maize, using stable isotope analysis of blood samples to track absorption rates. The study population consists of school-aged children aged 10-14 years old in the Western Highlands of Guatemala near Tecpán, Chimaltenango.10
While blood samples have already been collected as part of DIV funding, additional funding is needed to complete sample analysis, data analysis, and publication of results.11 This grant is time-sensitive because the collected samples are frozen but may degrade over time. The biomarkers are expected to remain stable for approximately six months from collection, with a deadline of June 2025 for analysis.12
Budget for grant activities
The $175,212 grant covers activities by two research institutions.13 Semilla Nueva told us that the budget is structured so that the completion of a milestone unlocks a certain amount of funding. While some of the activities below have already been completed, the corresponding portion of the budget was not disbursed.14
University of Colorado Denver ($145,277):
| Milestone | Amount unlocked |
|---|---|
| Complete purification and stable isotope analysis of samples from the bioavailability study | $120,277 |
| Publication draft submitted to an academic journal | $20,000 |
| Participate in public dissemination of findings among relevant stakeholders | $5,000 |
| Total | $145,277 |
Instituto de Nutrición de Centro América y Panamá (INCAP) ($29,935):
| Activity | Amount |
|---|---|
| Conduct information sessions with study participants, recruit and enroll 56 participants, complete field activities and ship samples to CU Denver | $15,000 |
| Clean data, review results, and present initial findings | $5,000 |
| Submit publication draft to academic journal | $5,000 |
| Participate in public dissemination of findings | $4,935 |
| Total | $29,935 |
The case for the grant
We are recommending this grant because:
- We think biofortification could be a promising intervention for addressing micronutrient deficiencies. We think this grant will provide some learning value for biofortification as a potential approach for addressing iron deficiency in Sub-Saharan Africa, where we think we are less likely to find large-scale social protection programs distributing fortified staples and well-established supply chains, which limits the applicability of large-scale fortification and supplementation programs.
- We think Semilla Nueva’s program could be cost-effective. We roughly estimate that Semilla Nueva's biofortification program is currently 3-8 times as cost-effective as cash transfers.15
This estimate is based on an unpublished 2017 analysis that estimated 2.6 times the cost-effectiveness of cash transfers. However, we expect that estimate understates the true cost-effectiveness because:
- The 2017 analysis only included future income benefits for children exposed to the program from ages 0 to 2, which likely underestimates total benefits since children who consume biofortified maize at older ages would also experience improved nutrition and future income.
- It does not reflect the impact that Semilla Nueva expects to achieve by crowding in government funds for seed subsidies, which it thinks will reduce program costs over time.
- The previous analysis only accounts for the benefits of added zinc and protein quality. It does not include possible iron benefits, which this study is designed to measure.
-
We think there is approximately a 20% chance that biofortification will meet our cost-effectiveness threshold (10 times as cost-effective as cash transfers) in the long run because:
- Semilla Nueva estimates costs will decrease by approximately 35% due to economies of scale and expected improvements in yields from their seed breeding program.16
- The grant leverages significant prior investment and is time sensitive. We would be leveraging $260,000 that has already been spent on this study. The samples have been collected and the study infrastructure is in place, but samples may degrade if not analyzed promptly, with a June 2025 deadline for maintaining sample integrity. Semilla Nueva was unable to find alternative funding, so we believe this study would likely go unfunded without this support.17
Risks and reservations
Our main reservations about this grant are:
- We conducted limited due diligence due to time sensitivity. The risk of sample degradation meant we had to make this funding decision quickly. As a result, we have not had time to review the study protocol in detail or triangulate key claims, such as the study's value to the broader research community or the likelihood that samples have already degraded.
- We are unsure about the program’s cost-effectiveness and room for more funding. Our uncertain estimate is that this program could be 3-8x cash, but we do not yet have a full cost-effectiveness model for biofortification. We also don’t have an estimate of room for more funding for biofortification programs in geographies where we think they could effectively address iron deficiency anemia. For example, we have not analyzed whether maize consumption patterns align with areas of high iron deficiency prevalence in Sub-Saharan Africa. It’s also possible that opportunities for government leverage may be limited in Sub-Saharan Africa.
Plans for follow up
We expect to receive preliminary study results by early 2026. These results will inform our understanding of biofortification's potential benefits and our decisions about future funding in this area.
Internal forecasts
For this grant, we are recording the following forecasts:
| Confidence | Prediction | By time | Resolution |
|---|---|---|---|
| 35% | We will make an additional grant to Semilla Nueva's program in the next 3 years | June 2028 | - |
Our process
- Semilla Nueva contacted us in March 2025 through an introduction from Taimaka
- We held two calls with Semilla Nueva and exchanged several emails
- Given the time-sensitive nature of the funding gap, we conducted a limited investigation
Relationship disclosures
None.
Sources
- 1
Our understanding of Semilla Nueva's work comes primarily from the conversations we've had with them. More general information on Semilla Nueva's work can be viewed on Semilla Nueva's website here, with more in depth reports found here.
- 2
Semilla Nueva, Conversation with GiveWell, June 5, 2025
- 3
Semilla Nueva, Conversation with GiveWell, June 5, 2025
- 4
"Biofortification is the process by which the nutrient density of food crops is increased through conventional plant breeding, and/or improved agronomic practices and/or modern biotechnology without sacrificing any characteristic that is preferred by consumers or most importantly to farmers (1). It is recognized as a nutrition-sensitive agriculture intervention that can reduce vitamin and mineral deficiency (2)." Talsma & Pachón 2017
- 5
Semilla Nueva, Conversation with GiveWell, March 12, 2025 (unpublished)
- 6
Semilla Nueva, Conversation with GiveWell, March 12, 2025 (unpublished)
- 7
Semilla Nueva, Bioavailability study budget scenario (May 2025)
- 8
Semilla Nueva, Conversation with GiveWell, June 5, 2025
- 9
Semilla Nueva, Conversation with GiveWell, March 12, 2025 (unpublished)
- 10
“The overall goal of this study is to determine the amount of zinc and iron absorbed from tortillas made with nixtamalized biofortified maize compared to nixtamalized non-biofortified maize. Zinc and iron deficiencies are common in Guatemala, and maize is a staple food throughout the country. This study will demonstrate if utilizing nixtamalized biofortified maize has the potential to increase dietary zinc and iron intake and improve zinc and iron status when compared to diets incorporating traditional maize. The proposed study setting is in the Western Highlands of Guatemala near Tecpán, Chimaltenango, and the population to be studied is school-aged children 10-14 years old.” Semilla Nueva, AMAIZING study protocol, 2024
- 11
Semilla Nueva, Conversation with GiveWell, March 12, 2025 (unpublished)
- 12
Semilla Nueva, Conversation with GiveWell, March 12, 2025 (unpublished)
- 13
Semilla Nueva, Bioavailability study budget scenario (May 2025)
- 14
Semilla Nueva, Conversation with GiveWell, June 6, 2025 (unpublished)
- 15
- To date, GiveWell has used GiveDirectly's unconditional cash transfers as a benchmark for comparing the cost-effectiveness of different funding opportunities, which we describe in multiples of "cash” (more). In 2024, we re-evaluated the cost effectiveness of direct cash transfers as implemented by GiveDirectly and we now estimate that their cash program is 3 to 4 times more cost-effective than we’d previously estimated (more).
- For the time being, we continue to use our estimate of the effectiveness of unconditional cash transfers prior to the update to preserve our ability to compare across programs, while we reevaluate the benchmark we want to use to measure and communicate cost-effectiveness.
- Note that a) our cost-effectiveness analyses are simplified models that are highly uncertain, and b) our cost-effectiveness threshold for directing funding to particular programs changes periodically. See GiveWell's Cost-Effectiveness Analyses webpage for more information about how we use cost-effectiveness estimates in our grantmaking.
- 16
“Driver 1: economies of scale: Most of Semilla Nueva’s costs are fixed (monitoring and evaluation, seed development, advocacy, etc). The subsidy itself is normally less than 20% of our budget. In 2025, for example, off a $5.7M total budget, less than $1M will be for the seed subsidy (of which $650k is paid for by the government). By 2027, we estimate fixed costs will stay at about $6M, with $2M of additional funding for the subsidy (mostly covered by the government). In this way, the total spend for Guatemala (SN and government) will increase less than 25%, while the number of farmers served is expected to nearly triple compared to 2024. Given all of this, we expect that our cost per farmer will decrease 30% between the 2021-2023 averages (which the CEA is built off) and 2027. This is reflected in cell C5 of our updated CEA.
Driver 2: higher yielding biofortified seeds: Our breeding program is getting more efficient at taking leading seeds for a region and breeding them to be nutritious. The new seeds we’ve already developed (with launch in 2026 and full roll out in 2027) will increase yield for farmers by 10-20% and cut costs for seed companies by 10-20% (according to two years of testing data, which is in our bi-annual reports). In our estimates for the CEA we’re conservatively assuming 10% higher yield for the new seeds. This is reflected in cells C9, C16, and C35.
We believe this will simultaneously drive production from seed companies and demand from farmers–while increasing the amount of biofortified maize that each farmer is producing (translating into both more biofortified maize consumed and more farmer income). Sales of our seed increased 89% between 2023 and 2024, and we’re projecting a 120% increase for this year.”
Semilla Nueva, Email to GiveWell, May 29, 2025 (unpublished) - 17
Semilla Nueva, Conversation with GiveWell, June 5, 2025