CIA prescribed a proper diet for U-2 pilots to avoid all their “call of nature”

Beginning in the 1950s, the CIA’s U-2 program launched secret surveillance missions against the Soviet Union, China, and other countries. The missions were carried out in utmost secrecy and tightly controlled, so much so that the agency had strict living guidelines for pilots before and after missions.

The U-2 was built with a “relief tube” for urination, since no human could hold their bladder for nine hours. However, the secret aircraft did not have a mechanism for defecation. To get around this problem, the CIA, presumably using registered dietitians, recommended “high protein, low residue” diets to minimize poop creation.

Muckrock, a Freedom of Information Act website, recently posted online the CIA’s “U-2 Pilot Physical Maintenance Control Program.” The formerly top-secret manual includes tips to avoid needing to go toilet at 60 000 feet altimeter.