The madness of George Frideric Handel

It is not recorded what was served, but, having eaten, Handel excused himself from the dinner table, leaving Goupy alone. Time passed and Goupy wondered what had happened to his host. He went to look for him and, upon opening the door to the next room, glimpsed Handel through the window, standing in the back parlour stuffing himself with "such delicacies as he had lamented his inability to afford his friend".

Goupy, a painter and set-designer whose patron was Frederick, Prince of Wales, was not pleased. He left in a fury and set to work with his chalks to wreak his revenge. The result was perhaps the most notorious caricature of Handel, entitled The Charming Brute, which showed the composer of the Messiah with a pig's snout seated at the organ on a barrel of wine, a brace of fowl hanging from the pipes and further supplies stacked behind him. The picture, unsurprisingly, ended their friendship.

David Hunter, a Handel specialist and curator at the Fine Arts Library of the University of Texas in Houston, is more sympathetic. George Frideric Handel, celebrated not only for his glorious Baroque music but also as an interpreter of human character, was, he says, not a moral reprobate but the victim of a pathological condition – a compulsion to eat. That in turn resulted in chronic lead poisoning – chiefly from the quantity of wine he imbibed – which influenced the course of his musical development.

Dr Hunter tells the story of Goupy's unhappy dinner in a chapter he has written for the catalogue of a new exhibition in the house where the events took place – 25 Brook Street, Mayfair, now the Handel Museum. Handel was the first occupant of the house after it was built in 1723 and he died in his bedroom there 36 years later, in 1759. For many years until his death he was blind, suffered paralytic attacks, severe gout and difficulties with speaking and thinking. He was also severely overweight – a rarity among 18th-century musicians.

What was the cause? From a study of the portraits and contemporary descriptions of the composer, Dr Hunter believes he was suffering from binge-eating disorder.

He said: "Handel became obese and it is likely that he could not control his appetite. During his travels in Europe he incurred huge food bills and his first biographer noted that he was 'habituated to an uncommon portion of food and nourishment'. The evidence suggests he suffered from what we would now call a binge-eating disorder, defined in his day as an 'extraordinary appetite' and an 'inordinate extravagant hunger'.

"It was not a moral problem, even though it has been cast as such by commentators. It was more likely something in his genetic make-up. But we can only go so far with retrospective diagnosis. We are very dependent on first-hand accounts of people who knew him."

Early biographers frequently referred to Handel's size. John Hawkins wrote that he was "in his person a large and portly man", adding: "His gait which was ever sauntering, was rather ungraceful as it had in it somewhat of that rocking motion which distinguishes those whose legs are bowed."

William Coxe, referring to Handel's "natural corpulency which increased as he advanced in age", noted a remark of the actor James Quinn that "his hands were feet and his fingers toes".

But perhaps the most revealing is an account by George Harris, brother of James, who was a close friend of Handel's and whose house in Salisbury the composer had visited. Writing in 1743, Harris described seeing him in the park, looking well. "I am told he would probably recover his health again were he not so much of the epicure that he cannot forbear going back to his former luxurious way of living which will in the end certainly prove fatal to him."

Dr Hunter said: "The suggestion is that he had a compulsion or something that manifested itself in compulsive behaviour rather than a physical inadequacy."

His overeating and drinking led to an inevitable consequence: the ingestion of large quantities of lead. Lead poisoning was well recognised among workers exposed to the metal in the 18th century but was often missed in the wealthy who drank and ate in large quantities. Wine was a particular risk. Vintners who wished to import wine faced the problem of keeping it in good condition while it was shipped when barrels could not be relied on to be airtight. To stop the wine turning to vinegar they sometimes added lead shot to reduce the action of bacteria.

Lead was also used to clarify wine and in "sapa", the process of sweetening wine of poor vintage with grape juice boiled in lead vessels. Lead also contaminated beer, cider, gin, food, water and cosmetics, including the white powder used under wigs.

The symptoms of lead poisoning were those which Handel is reported to have suffered: stomach colic, pain, creeping paralysis, confusion and eventually blindness. The toxin also affects mood and may have accounted for Handel's famous ill temper when working with other musicians.

A key moment came in 1737 when, suffering with a paralysed right hand, Handel sought treatment in the spa town of Aix la Chapelles, now known as Aachen. Several months of taking the waters, bathing and resting – and avoiding heavy eating and drinking – worked their magic. His hand was restored, enabling him to play the harpsichord again, and write. The nuns at Aix attributed his recovery to a miracle. It was not a miracle but exactly what you would expect of someone who was suffering from lead poisoning, the effects of which last only as long as exposure to the toxin. Once the poison is removed, the symptoms disappear.

Dr Hunter believes this experience had a lasting effect. "It was partly as a result of the paralysis he suffered and the subsequent cure that he moved more into writing oratorios than operas. His increasing infirmity, his experience of major pain – probably for the first time – and his sensitivity to his own mortality made him more interested in writing about suffering and personal stories than about gods, monarchs and heroes. There is a sense in which you can see the change taking place; there is a greater sensitivity to suffering. Musically it is evident too in his greater use of the minor key."

There followed some of his greatest works including Messiah, Solomon and Israel in Egypt, each supreme examples of the oratorio genre.

His recovery did not last and there were to be many subsequent visits to Aix, each time the symptoms of poisoning overwhelmed him. Each time he found relief as the metal was purged from his system. The score for his final piece of music, Jephtha, written in his own hand, includes the note in German dated 13 February 1751: "Unable to go on owing to a weakening of the sight of my left eye." Yet 10 days later he was able to work again and completed the score by the end of August the same year.

For the last eight years of his life he endured progressively worsening health. On the evening before he died, on 14 April 1759, he announced he would no longer be receiving guests at the house in Brook Street, as by that stage he was "done with the world". Two hundred and fifty years later, it is apparent the world has not done with him.

Handel Reveal'd is at the Handel House Museum from 8 April to 25 October

Tortured geniuses: Composers on the edge

Wolfgang Amadeus Mozart (1756-1791)

The composer suffered from manic depression and died at the age of 35 following a short illness.

Ludwig van Beethoven (1770-1827)

Started to lose his hearing in his twenties. Personal letters confirm that he suffered from depression and alcoholism.

Robert Schumann (1810-1856)

The German composer suffered from depression, widely believed to be the result of syphilis. After experiencing a number of 'visions' he attempted suicide by throwing himself off a bridge into the Rhine. He later admitted himself into an insane asylum where he died two years later.

Pyotr Tchaikovsky (1840-1893)

Although immensely popular during his lifetime, Tchaikovsky was never emotionally secure. His life was punctuated by personal crises and periods of depression, partly due to his suppressed homosexuality and subsequent disastrous marriage. His sudden death at the age of 53 is generally ascribed to cholera, but some believe he committed suicide.

Gustav Mahler (1860-1911)

After the death of his first child, Mahler plunged into depression that was intensified when he was diagnosed with a heart disease.