(1) retinol in animal foods is vitamin A classes, found in animal liver, cod liver oil, eggs, dairy and other animal foods;
(2) carotenoid pigment found in a small amount of flying fruit and vegetables;
(3)-carotene into the human body can be converted to vitamin A;
(4) and more vegetables have carotene content Hu Luoka, spinach, leek, canola, celery leaves' tomatoes, peppers, squash and so on.
In vitamin A, vitamin anti-cancer effect is most prominent carotene, eat more foods containing carotenoids is beneficial to humans.
Anticancer effect of vitamin, carotene itself is non-toxic, has no side effects accumulate, does not cause poisoning. Liver is very rich in vitamin A, but its existence is a form of vitamin A palmitate enzyme hydrolysis in the body after the formation of vitamin A into the blood, excessive consumption may lead poisoning, it should not be too fresh animal liver.
Vitamin anti-cancer effects, such as serving of vitamin A pills, adult day one that had enough (content of 25,000 international units), if the long-term large numbers of vitamin A, the daily dose of more than 30,000 international units of toxic reactions may occur , headache, bone pain, loss of appetite, fatigue, irritability and other symptoms, so do not take vitamin A as possible, we should not eat any, to take under the guidance of physicians, for reasonable and safe.