Paul E. Johnson, 65, an authority on food and nutrition and a retired staff member of the National Academy of Sciences/National Research Council, died Sunday at his home in Washington after an apparent heart attack.

He had served as executive secretary of the academy's food protection committee from 1954 through 1971, and of its food and nutrition board from 1971 through 1976. Since then, he had been a consultant to the board.

Under Dr. Johnson's tenure, the Food Chemicals Codex, which provides specifications for food grade chemicals, was compiled.

He was a U.S. delegate to the First Joint Conference on Food Additives called by the United Nations Organizations and was a member of the First Joint Expert Committee on Food Additives of the Organizations.

Dr. Johnson also was a nutritionist on U.S. teams assessing the nutrition and food resources of Lebanon, Jordan and Nigeria.

He was a member of the pesticide advisory committee to the Secretary of health, Education, and Welfare, and served on the harzardous materials advisory committee to the Environmental Protection Agency.

He had participated in an Agriculture Department food mission to Europe and served on the food and nutrition liaison committee of the Nutrition Foundation.

Born in Chama, N. M., Dr. Johnson graduated from Park College in Missouri, earned a master's degree from the University of Missouri and received a doctorate from Cornell University.

He served on the staffs of agricultural experimental stations in North Dakota and Louisiara. During World War II, he was a nutrition officer in the Army's Sanitary Corps and saw duty in India.

After the war, he worked as a nutritionist with the Tennessee Valley Authority until coming to Washington in 1954.

He is survived by his wife, Lulu Mae, of the home, and a daughter, Eleanor Anne, of Kensington.