The public image of President John F Kennedy - whose 50th assassination anniversary is to be commemorated with a wreath-laying ceremony at Arlington National Cemetery in Virginia - was one of health and vigour.
The youngest man ever elected president in 1960, Kennedy christened a "Camelot" era of human rights and economic progress for the world's number one power. Crystallised by his assassination, the myth still endures today, together with that image of mesmerising youth and male beauty.
But few people suspect that behind that mask of strength and shape was a very sick man.
An article published in Annals of Internal Medicine by Dr Lee Mandel in 2009, which analyses the massive volume of medical records at the John F Kennedy Presidential Library and Museum in Boston, explores "the most complex medical history of any US president".
As a young man, Kennedy was diagnosed with Addison's disease, a condition hidden from the media and denied by his physician in the 1960 presidential campaign. Mandel implied that the president suffered a rare disorder called auto-immune poly-endocrine syndrome type 2 (APS-2), which can lead to Addison's disease, hypothyroidism and other glandular diseases.
Addison's, which occurs when the adrenal glands do not produce enough hormones, was diagnosed when Kennedy was 30. In September 1947, the then congressman Kennedy collapsed on a visit to the UK. A physician told Kennedy's friend Pamela Churchill: "That young American friend of yours, he hasn't got a year to live."
The symptoms of Addison's lead to fatigue, extreme weakness and substantial weight loss - all experienced by Kennedy before starting he went into therapy.
But the condition, categorically denied by Dr Janet Travell during the presidential campaign, was not all Kennedy was going through. The president also had hypothyroidism. Symptoms include depression, a puffy face and joint and muscle pains.
The combination of the two is explained by APS 2, also known as Schmidt syndrome, a condition in which the body cannot produce several essential hormones, leading to serious problems with their sex glands, pancreas and digestive system.
Two of Kennedy's relatives had similar diseases. His younger sister Eunice, who died at 88, had Addison's disease. His son, John F Kennedy Jr, had Graves disease.
The list of Kennedy's medications is shocking. On a typical day, Kennedy was taking ascorbic acid (500mg) twice a day; hydrocortisone (10mg); prednisone (2,5mg) twice a day; methyltestosterone (10 mg/d); liothyronine sodium (25mg) twice daily; ﬂudrocortisone (0.1 mg/d); and diphenoxylate hydrochloride and atropine sulfate, 2 tablets as needed.
Testosterone, in particular, was taken daily by Kennedy during his entire presidency - and on several occasions increased to 25mg/d.
His doctors claimed that the president was taking testosterone to keep his weight up. He also suffered from gastrointestinal symptoms (cramps, diarrhoea, inability to gain weight) for most of his life - further proof that he was a victim of autoimmune conditions.
But JFK enjoyed a good level of privacy, almost secrecy, compared to politicians in the NSA scandal era, and these findings were not known by the general public.
"Kennedy had more medical issues than most of us were aware of," said Mandel, a specialist in internal medicine and an amateur historian.
"But he got the job done despite all of those conditions. I admire the man."