Why supplement?
Carotenoid source
Helps provide a convertible vitamin A source that supports vision and immune function.
Nutritional evidence: EstablishedSupports normal vision
Vitamin A is a key component of rhodopsin, especially for low-light vision.
Mechanism: EstablishedSupports immune function
Vitamin A is involved in the immune barrier and normal immune-cell function.
Nutrition consensus: EstablishedHow to take it
Follow the product label and professional advice.
How oftenStay near the recommended daily intake; do not raise the dose on your own long term.
What to watch
Cautions
People who smoke should not self-start high-dose beta-carotene supplements.
Pregnant people should not self-start high-dose preformed vitamin A; excess can harm the fetus.
People with liver disease or taking vitamin A medicines should ask a doctor first.
· Nausea or headache (high doses)
· Dry skin (long-term high doses)
· Chronic excess can injure the liver and raise intracranial pressure.
Long-term dependenceNot addictive; fat-soluble vitamins can be stored, so high long-term doses carry toxicity risk.