His great size and his continued growth in adulthood was due to hypertrophy of his pituitary gland, which results in an abnormally high level of human growth hormone.
He was born on February 22, 1918 to Addie Johnson and Harold Franklin Wadlow. By the time he was in kindergarten, he was 5ft 4 inches tall. He outgrew his dad by his 8th birthday.
Trying to maintain a normal life, Robert enjoyed collecting stamps, photography, and become the world's tallest Boy Scout at 7'4", when he was 13 years of age. Later, he became a member of DeMolay and the Masons.
On July 4, 1940, during a professional appearance at the Manistee National Forest Festival, a faulty brace irritated his ankle, causing a blister and subsequent infection. Doctors treated him with a blood transfusion and emergency surgery, but his condition worsened, and on July 15, 1940, he died in his sleep at age 22.
Wadlow's funeral on July 19. He was buried in a 10-foot-long (3.0 m), half-ton coffin that required twelve pallbearers to carry and was interred in a vault of solid concrete. It was believed that Wadlow's family members were concerned for the sanctity of his body after his death, and wanted to ensure it would not be disturbed or stolen.
- By the time he graduated from college, he was 8ft 3in.
- When he was 13, he was also the world's tallest boy scout at 7ft 4in.
- Despite the fact that he had little feeling in his feet, he never used a wheelchair.
- He wore size 37AA shoes, which could cost up to $100 per pair.
- His clothing required 3x the regular amount of cloth.
- Over 40,000 people attended his funeral when he died.
- He was very fond of his mother, Addie Johnson.
- When he was five, he wore clothes that would fit a regular sized 17-year-old boy.
- Despite Robert's size, all of his family members were of normal height and weight.
- Robert was entombed in a coffin 10 feet long and weighing 1,000 pounds, requiring a dozen pallbearers and eight other assistants.
- Upon the death of Robert Wadlow, his family had almost all of his belongings destroyed. They didn’t want collectors to purchase his clothing and other items to be displayed as any kind of "freak" memorabilia.
- He showed no indication of an end to his growth even at the time of his death.
- One year before his death, he passed John Rogan as the tallest person ever.
- His middle name, Pershing, was in honor of the World War I General Pershing, then commanding officer of the European conflict.