Babies who take zinc supplements for two weeks show a clear rise in zinc levels in their blood, while those who don’t take supplements show little change.
Evidence from Studies
No evidence studies found yet.
What Would Prove This
Per GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this claim, ordered from strongest to weakest.
Whether zinc supplementation at 20 mg/day consistently raises serum zinc levels across diverse infant populations, accounting for formulation, baseline status, and duration.
A systematic review and meta-analysis of all randomized controlled trials measuring serum zinc levels before and after 7–14 days of zinc supplementation (10–20 mg/day) in infants aged 6–24 months, stratified by formulation (sulfate, bisglycinate, acetate) and baseline zinc status.
Whether 20 mg/day zinc supplementation reliably elevates serum zinc levels in infants with confirmed deficiency.
A double-blind RCT with 150 infants aged 6–14 months and baseline serum zinc <70 mg/dL, randomized to 20 mg/day zinc bisglycinate or placebo for 14 days, with serum zinc measured at baseline, day 7, and day 14 using standardized atomic absorption spectrometry.
Whether daily zinc supplementation leads to sustained higher serum zinc levels over 6–12 months in infants in low-resource settings.
A prospective cohort study measuring serum zinc levels monthly in 500 infants aged 6–24 months receiving daily zinc supplements (20 mg/day) versus 500 matched controls not receiving supplements, over a 12-month period in a region with high zinc deficiency prevalence.
Whether infants receiving zinc supplements have higher serum zinc levels than non-supplemented infants at a single point in time.
A cross-sectional survey measuring serum zinc levels in 1,000 infants aged 6–18 months, comparing those reporting daily zinc supplementation for ≥7 days in the past month to those who did not, adjusting for age, diet, and recent illness.
Whether a single infant shows a marked increase in serum zinc after supplementation.
A case series reporting serum zinc levels before and after 14 days of 20 mg/day zinc supplementation in 5 infants with documented deficiency and poor dietary intake.