[en] Background: Supplementing young children’s diets with small-quantity lipid-based nutrient supplements (LNS) may prevent growth restriction, but the optimal amount of zinc to include in these products is uncertain. Objectives: To assess zinc-related functional responses among young Burkinabe children who received LNS without or with varied amounts of zinc, and to compare these outcomes among children who do or do not receive LNS and selected health services. Methods: In a partially masked, placebo-controlled, randomized trial, 34 communities were assigned to immediate (II) or non-intervention (NI) cohorts. 2469 eligible II children were randomly assigned to 1 of 4 groups to receive LNS containing 0, 5 or 10 mg zinc (and placebo tablet) or LNS without zinc and 5 mg zinc tablet from 9 to 18 months of age. The daily ration of LNS was 20 g which provided 118 kcal along with 20 other micronutrients in addition to zinc. Weekly morbidity surveillance was conducted at children’s homes; malaria treatment was provided for confirmed malaria, and ORS for reported diarrhea. Children in NI (n = 797) received neither supplements nor illness treatment. At 9 and 18 months, length, weight, mid-upper arm circumference (MUAC) and hemoglobin (Hb) concentration were measured in all children. Results: Reported adherence was 97 ± 5% for LNS and tablets. Mean baseline Hb was 89 ± 15 g/L, and 91% were anemic (Hb <110 g/L). At 18 months, change in Hb was greater in II cohort than NI (+8 vs -1 g/L, p<0.0001), but 79% of II were still anemic (vs. 91% in NI). During the 9 month follow-up in the II cohort, the incidence of diarrhea and malaria was 1.15 ± 1.18 and 0.55 ± 0.54 episodes per 100 child-days, respectively and did not differ by intervention group. At baseline, mean length-for-age z-score (LAZ), weight-for-length z-score (WLZ) and MUAC were -1.21 ± 1.10, -0.99 ± 1.05 and 133 ± 12 mm, respectively, in all groups combined. Mean length, weight and MUAC were significantly greater at 18 months in II children (p<0.0001) compared to NI, but did not differ by II group. Stunting prevalence at 18 months was 39% in NI and significantly lower (29%) in II cohort (p<0.0001). The prevalence of moderate acute malnutrition (MAM; defined as 115 mm ≤ MUAC < 125 mm) was significantly lower in II cohort at 18 months (7.1% in II vs 11.1% in NI, p = 0.001), but did not differ by II group. The difference in MAM prevalence between II (7.8%) and NI (10.5%) was marginally different (p = 0.058) when MAM was defined as -3 ≤ WLZ < -2. Conclusions: Providing 20 g of LNS daily with or without zinc along with malaria and diarrhea treatment significantly increased hemoglobin concentration and growth and reduced the prevalence of anemia, stunting and MAM in this population. (author)