Large amounts of vitamin A are found in beef liver and fish liver oils; smaller amounts are in egg yolks, butter and cream. Milk and some cereals are fortified with vitamin A and, per serving, provide about 10 percent of daily needs. And substances in dark green, leafy vegetables and yellow vegetables and fruits are converted to vitamin A in the body.
Annette Dickinson, acting president of the trade group for supplement makers, the Council for Responsible Nutrition, said the Swedish men had an unusually high intake of vitamin A, even though very few were taking supplements. “I don’t think there’s a reason now from the studies we have before us to say that multivitamins containing ordinary amounts of vitamin A are harmful,” Dickinson said. She said that in many multivitamins, much of the vitamin A is in the form of beta-carotene, which studies have shown does not weaken bones. The study had some shortcomings: Blood levels of vitamin A were measured only once, and the participants’ reports of diet and supplement use 20 years later did not match well with their earlier vitamin A blood levels.