Dr. Robert L. Vought, 70 an epidemiologist and retired official of the National Insitutes of Health, died Friday in a Sarasota, Fla., hospital after a heart attack. He had moved to Florida in November 1978.

He was chief of the metabolic dieases epidemiological unit at the National Institute of Arthritis, Metabolic and Digestive Diseases for 17 years before retiring in 1978.

Dr. Vought was an authority in epidemiology, metabolic diseases and iodine metabolism.

A native to Bradford County, Pa., he came to Washington during his youth and graduated from Eastern High School. He earned his medical degree at Syracuse University and a master's degree in public health at Johns Hopkins University.

During World War II, he helped direct Army typhus control programs in Guatemala and Ecuador. He retired from active duty in 1947 with the rank of lieutenant colonel.

Dr. Vought joined NIH in 1961 after spending six years as medical coordination director of Bristol Labs in New York City. Prior to that, he had practiced medicine and worked as a public health officer in New York State. He had taught at Columbia University's School of Public Health from 1951 to 1955.

He was the author of more than 40 technical works on iodine metabolism and diseases of the goiter.

Dr. Vought was a fellow of the American Public Health Association and a member of both the American Thyroid Association and the Society of Epidemiological Research.

He is survived by his wife, Florence, of the home in Sarasota; three daughters, Linda Taylor of Richmond, Va., Martha Richcreek of New Carrolton, and Helen Zunt of Nokomis, Fia., and nine grandchildren.

The family suggests that expressions of sympathy be in the form of contributions to the American Heart Association.