Vitamin A is a group of fat-soluble retinoids essential for vision, immune function, cellular communication, and reproduction. While critical for health, its role in longevity is primarily about preventing deficiency. For well-nourished individuals, high-dose supplementation with preformed Vitamin A (retinol) does not confer additional healthspan benefits and can be toxic, potentially increasing all-cause mortality.
Verdict
Avoid supplementation unless deficient; obtain from a balanced diet.
HEALTHSPAN IMPACT
Experimental
RISK LEVEL
High
EVIDENCE GRADE
A
MONTHLY COST
$5 - $15
Protocol
- Supplementation is generally not recommended for healthspan unless a clinical deficiency is diagnosed.
- Dietary intake is preferred, aiming for the RDA of 700-900 mcg RAE daily.
Flags
- Toxicity (hypervitaminosis A) from preformed Vitamin A is a significant and well-documented risk.
- High intake is teratogenic and should be avoided during pregnancy.
- Beta-carotene supplements have been linked to increased lung cancer risk in smokers.
- Obtain from a balanced diet rather than relying on high-dose supplements.
- Interacts with retinoid drugs (e.g., isotretinoin) and drugs affecting fat absorption.