NEW YORK (CNN) -- In death even as in life, Dr. Benjamin Spock's pronouncements on raising children are sparking sharp debate.

In the newly updated edition of the noted pediatrician's landmark book, "Baby and Child Care," Spock, who died in March, advocates a vegetarian diet for children and urges parents not to give them milk or other dairy products after the age of 2.

But some nutritionists and pediatricians -- including Spock's own co-author -- disagree with his recommendations.

Noted child expert Dr. T. Berry Brazelton, a friend of Spock, went so far as to call them "absolutely insane" in an interview with The New York Times.

"Meat is an excellent source of the iron and protein children need, and to take away milk from children, I think that's really dangerous. Milk is needed for calcium and vitamin D," Brazelton said.

The call for no meat or dairy products for children marks a change for "Baby and Child Care," which was first published in 1946 and has sold more copies in the United States than any book except the Bible. In the first six editions of the book, Spock consistently recommended meat and dairy products for children.

But in 1991, Spock himself embraced vegetarianism at the age of 88, lost 50 pounds and conquered chronic bronchitis. And in the latest edition, he urges parents to start children on the vegetarian road early in life because "when children develop a taste for meats, it is hard to break this habit later on."

"Children who grow up getting nutrition from plant foods rather than meats have a tremendous health advantage. They are less likely to develop weight problems, diabetes, high blood pressure and some forms of cancer," writes Spock.

He also advised that growing kids can get the calcium they need from leafy green vegetables, soy milk and beans, rather than from cow's milk and dairy products, which he says are too high in fat and can aggravate conditions such as asthma and chronic ear infections.

Spock's co-author, Dr. Steven J. Parker, who disagreed with the recommendations, told The New York Times that Spock believed a vegetarian diet had "given him a new lease on life" and that he wanted the latest issue of his book to be "in the forefront" of linking animal-based foods to disease.