In 2025, donations made through Mieux Donner directed €357,430 to Helen Keller Intl's vitamin A supplementation programme. Here's what that sum represents, and why GiveWell counts this programme among the most cost-effective it recommends.
Vitamin A is essential for young children's developing immune systems. In low-income countries, diets that lack it leave children vulnerable to common infections: severe diarrhoea, measles, respiratory infections and malaria. These illnesses are mild where ordinary healthcare is available, but they can kill a child who is deficient.
Deficiency also causes night blindness and, in severe cases, permanent loss of sight. The WHO lists it among the leading causes of preventable blindness in children worldwide.
Helen Keller Intl is GiveWell's recommended charity for vitamin A supplementation. Working with health ministries, it runs two distribution campaigns a year for children aged 6 to 59 months. In 2025, 94.4 million capsules were distributed across 14 African countries.
In the countries where Helen Keller Intl works, children aged 1 to 5 make up around 18% of the population. A region of one million people therefore has roughly 180,000 children eligible for vitamin A. In France, the same age group makes up 5.1% of the population: you would need 3.5 million people to find as many children.
These children live in a very different reality from ours. In some parts of sub-Saharan Africa covered by the programme, nearly one child in ten dies before the age of five. Almost every parent there knows a child who has died of diarrhoea, measles or an infection. Vitamin A doesn't cure any of these diseases: it makes them less likely to kill.
Sources: Cochrane 2017, GiveWell. The reductions cited come from meta-analyses of randomised controlled trials.
Here is what the €357,430 directed to this programme by donors giving through Mieux Donner in 2025 means in practice.
Calculation: €1 per capsule (GiveWell, February 2024), 2 capsules per child per year. The monthly figure is an average, as donations are concentrated at the end of the year. The two geographical comparisons have the same number of children but not the same number of people. Children aged 1 to 5 make up around 18% of the population in sub-Saharan Africa, compared with 5.1% in France (3.5 million children out of 69.1 million people, INSEE 2026). For the same number of children, the French population needs to be three and a half times larger.
Vitamin A deficiency doesn't only kill. It also robs children of their sight as soon as the light fades. Night blindness, the inability to see in the dark, is the first visible sign of deficiency. For a child in a village without electricity, that means no more playing, getting around or joining in village life after sunset. If the deficiency persists, it leads to xerophthalmia: ulceration of the cornea and permanent loss of sight. Two capsules a year can prevent this process.
Helen Keller Intl works with the governments of Mali, Niger, Burkina Faso, Guinea, Cameroon, the Democratic Republic of the Congo and Nigeria. These are countries where deficiency is severe and where the expected impact per euro spent is highest.
This is the kind of region where Helen Keller Intl's campaigns take place. It's also the scale of what 2025 donations funded: €357,430 is enough to cover every child aged 1 to 5 in a region like Plateau-Central, an entire region of Burkina Faso, one of the countries where the charity runs GiveWell-funded distributions.
To picture its size, Plateau-Central covers 8,545 km², roughly the size of Corsica. Under-five mortality there remains among the highest in the world, and access to vitamin A-fortified food is very limited.
These stories are published by Helen Keller Intl from the countries where it runs its campaigns, the same countries funded by donations to this programme.
Abdoul Aziz Coulibaly, 4, Mali. From the age of one, Abdoul was in hospital at least twice a month. He also had night blindness: as soon as the sun went down, he couldn't see. His father Alou held out for more than a year before agreeing to the distribution, wary of free programmes. Two months after the first dose, his appetite was back, his night vision had returned, and he barely needed hospital care over the following six months. We tell his story in full in what life is like for a child with vitamin A deficiency.
Source: Helen Keller Intl, From Vitamin A Skeptic to True Believer, 2024.
Aisha Abdullahi, mother, Nigeria. Health workers avoid travelling to this rural village, which is often affected by insecurity. The nomadic community was also wary of conventional medicine. When a Helen Keller Intl team came for a vitamin A campaign, few parents agreed at first. The charity began with informal education sessions to build trust and correct misconceptions before distributions could take place.
Source: Helen Keller Intl, Saving Sight and Lives with Micro but Mighty Vitamin A, 2025.
Baban Kori, mother, Niger. Recorded as part of the vitamin A supplementation programme in Niger, one of the charity's priority countries. What these mothers see day to day, comparing their children's health before and after the distributions, is in line with the epidemiological data.
Astrid Wanja Joe, nursing supervisor, Kenya. Trained by Helen Keller Intl to build vitamin A supplementation into routine visits, Astrid advises mothers on nutrition and the importance of the two yearly doses. She also runs campaigns in schools to reach children who don't attend clinics. Her story shows the charity's other approach: training local health workers so the effect lasts beyond one-off campaigns.
Source: Helen Keller Intl, Saving Sight and Lives with Micro but Mighty Vitamin A, 2025.
A note on method. These stories illustrate well-documented clinical effects of vitamin A deficiency and how they can be reversed. They can't be used to attribute any individual death averted. The effect of supplementation is shown at population level, through 19 randomised controlled trials, not for any one child.
GiveWell, the leading international evaluator for health and poverty, models the cost of averting a death. Its estimate accounts for the marginal causal effect of funding (the possibility that another charity or a government might have funded the campaign instead), the coverage actually achieved and the local mortality context. After these adjustments, the December 2024 grant works out at around $6,600 per child death averted on average.
A French benchmark. A working group of France's Commissariat général à la stratégie et à la prospective values a year of life in good health at around €180,000 (€150,000 in 2013, adjusted for inflation). This is the threshold implicitly used to weigh up reimbursements and public health investments. By that benchmark, French public health decisions would treat €357,430 as worth about two years of healthy life. The same sum given through Helen Keller Intl is estimated to produce several thousand. Find out more about the value of a statistical life.
What these numbers don't tell you. The number of deaths averted is a statistical estimate with real uncertainty. It depends on local mortality rates, the campaigns' actual coverage and the counterfactual scenario used. GiveWell publishes all its spreadsheets: we use its assumptions without adjusting them, and the order of magnitude matters more than the decimal point.
Not every eligible area is covered. In its December 2024 grant, GiveWell identified opportunities it didn't fund, either for lack of budget or because they fell just below its threshold: Côte d'Ivoire, several Nigerian states and expansion projects. Whole regions are ready to start supplementation campaigns as soon as funding arrives.
That's what makes this programme unusual: extra funding doesn't replace existing money, it can open up another area. So each new donation helps protect more children from deficiency.
A donation made through Mieux Donner goes to Helen Keller Intl at no extra cost and qualifies for France's 66% tax reduction. A €100 donation costs you €34 after tax relief, and funds around fifty children covered for a year.
DonateQuestions about the methodology or calculations? info@mieuxdonner.org · mieuxdonner.org
