Evidence brief · Supplement
Vitamin A for Deficiency / childhood mortality
Evidence grade A — In deficient populations
- Overall grade
- Grade A
- Last revised
- 1
- graded outcome
- 1
- reference listed
Assembled by the app from other entries in this library. It adds no evidence of its own — follow the links to the entries it draws on.
1 at grade A — 1 graded row
What is known
Each outcome with its grade (how strong the evidence is, A to D), the size of the effect where the entry records one, and how often studies agree.
- Deficiency / childhood mortalityEvidence grade A
In deficient populations
Largehigh
The evidence in words
The verdict
For deficiency / childhood mortality, Vitamin A earns evidence grade A (large effect, high consistency) — there is real evidence here. In deficient populations
How it might work
Retinal is the light-sensing chromophore in the retina; retinoic acid is a hormone-like regulator of gene transcription governing cell differentiation and immunity. Preformed A is fat-soluble and stored in the liver, so it accumulates — the reason chronic high intake is toxic.
How to use it
Food-first (liver, dairy, eggs, orange and dark-green vegetables). If supplementing, keep within the RDA range; pregnant women must avoid high preformed-retinol doses.
Safety & cautions
Chronic excess of preformed A causes liver damage, bone effects, and, in pregnancy, birth defects. Smokers should avoid beta-carotene supplements. Carotenoids from food are safe (at most, harmless skin yellowing).
Bottom line
A deficiency you fix, not a supplement you stack. Get it from food; avoid high-dose retinol in pregnancy and beta-carotene supplements if you smoke.
How it is used
As the entry records it, from the studies it summarises. Not a recommendation for you — doses that suit a trial population may not suit you.
- Food-first
- Liver, dairy, eggs, orange/green vegetables; supplement only within RDA.
Goes with
- Vitamin ARead the full Vitamin A monographEvidence grade B
Related reading
Entries that share this one's tags or conditions.
- Vitamin A for Lung cancer (beta-carotene, smokers)Evidence grade A — Increased risk — ATBC/CARETEvidence grade A
- Vitamin A: dosage and how to take itLiver, dairy, eggs, orange/green vegetables; supplement only within RDA.Evidence grade B
- Vitamin A: side effects, safety & interactionsChronic excess of preformed A causes liver damage, bone effects, and, in pregnancy, birth defects. Smokers should avoid Evidence grade B
- Andrographis for Common coldEvidence grade B — Severity and durationEvidence grade B
Sources
As this entry records them: title, journal and year. None carries a DOI or PubMed id, so none is linked as a verified paper. Each link searches PubMed for the title; check that what you find is what the entry describes.
- 1.Effect of beta-carotene and vitamin A on lung cancer (CARET) — N Engl J Med, 1996. Search PubMed (opens in a new tab)
Last revised . A grade is this entry's reading of the evidence, not medical advice.