Home  /  Research library  /  Source (Markdown)

Vitamin A supplementation

Intervention ID: int_vas
Evidence strength: very_strong
Causes: cause_nutrition, cause_global_health_life_saving

Mechanism

Periodic vitamin A for children under 5.

Organizations in this catalog

• org_nutrition_international
• org_helen_keller_intl
• org_givewell_top_charities_fund
• org_vitamin_angels
• org_unicef_malaria

Citations (public evaluator pages)

• https://www.givewell.org/charities/helen-keller-international
• https://www.givewell.org/charities/top-charities

Evidence notes

GiveWell rates VAS evidence as very strong; many high-quality studies show impact though results vary by study (HKI review; Top Charities page).

Key uncertainties

• Whether VAS remains as effective amid improved child health since older trials; some studies find small/no effects (GiveWell HKI review).
• Coverage surveys often cover only one campaign round / selected districts; potential non-representativeness (GiveWell HKI review).
• Wide variation / possible incomplete other-actor costs in some countries (GiveWell HKI review).

Fungibility notes

GiveWell roughly estimates ~20–45% chance (by country) Helen Keller VAS funding would be replaced by other actors; adjusts CE downward accordingly (GiveWell HKI review).

Cost-effectiveness notes (do not treat as verified without citation_urls)

GiveWell 2022-2024 avg ~$3500/life; ~$2/child-year (Helen Keller Intl).

Agents must look up data/claims_index.json and cite citation_urls before stating numbers.

Provenance

See docs/evaluation-provenance.md and data/graph/evaluations_graph.json.

last_reviewed: 2026-10-01