In September 1966, Ley took a leave of absence from his position to become director of the Bureau of Medicine of the
Food and Drug Administration and on July 1, 1968, he was appointed
Commissioner of the Food and Drug Administration by President
Lyndon B. Johnson. Ley served as FDA commissioner for only a year and a half; he was ousted in December 1969. Amidst the growth of the
environmental movement and its concern with chemicals, pressure mounted on the government to restrict the use of cyclamate. In October 1969,
Department of Health, Education & Welfare Secretary
Robert Finch bypassed Ley and the FDA, and removed the GRAS designation from cyclamate, banning its use in general purpose foods but keeping it available for restricted use in dietary products with additional labeling. In October 1970, a year after Ley left, the FDA banned cyclamate completely from all food and drug products in the United States. Dr. Ley was ousted from his Commissioner post on December 12, 1969, and was replaced by
Charles C. Edwards.
Reviews of his tenure In accepting Ley's resignation, Secretary of HEW Finch praised him as a "gifted scientist and a dedicated public servant," saying that he had "coped strenuously with an unwieldy agency". In September 1982, interviewed for the oral history program of the FDA History Office, Maurice D. Kinslow, Chairman of the committee and author of the final draft of the July 1969 "Kinslow report" characterized Dr. Ley as Commissioner: "Since I reported to him [Dr. Ley] as a District Director and subsequently took on the special assignment [Kinslow Report], I had a lot of personal contact with him. I found him to be a very honest, decent person to work for. I respect Herb Ley; he was very different that either
George P. Larrick or
James L. Goddard [Previous FDA Commissioners], but I'm convinced he was dedicated to the best interests of the American public. And indeed, I believe that he got into significant trouble during his last days in the agency during the fall of 1969, in connection with the banning of
cyclamates because he did what the Secretary told him to do (to not discuss the matter within the FDA). He was a good soldier." ==After the FDA==