Buenos Aires, Nov 10 - Some 400 clowns and doctors skilled at clowning took part in an international conference in Buenos Aires to present scientific evidence, backed by their own experience, to show why laughter was healthy.

The third International Congress of Hospital Clowns, which was held Nov 7-8 in the Argentine capital, brought together artists and health professionals from around the world who combine humour with health care, the Spanish news agency EFE reported.

"All over the world there are doctors who work with the art. Some put on clown noses and some don't. But in almost all regions, in Europe, the United States and Latin America, there are hospital clowns at work," said Argentina's Jose Pellucchi, artistic director of Payamedicos (Doctor-Clowns).

The organization has some 500 members, mostly doctors, specially trained in how to clown around with hospitalized patients to help them get better.

In European countries and the US, for example, there is a growing trend in medical centres to hire professionals with this comedic-therapeutic profile.

According to Pellucchi, using the clown's art in health care goes back to ancient Greece, where people with manic episodes were taken to see theatrical dramas, while those suffering depression were treated to comedies.

"There are pictures from the beginning of the 20th century that show the presence of clowns in hospitals. But the technique got a big boost from the movie "Patch Adams", the doctor said.

In the 1998 film Robin Williams plays Patch Adams, a US doctor who promoted "laugh therapy" and was responsible for making the technique a part of modern medicine.

Among other positive effects, Pellucchi said that his organization has studies showing that, after doctor-clown treatment, patients' blood pressure drops by 13 percent.

Among the lecturers at the congress was Argentina's Alejandro Gruber, who for years has worked in Israel where he founded a company of hospital clowns as part of a project that also encourages integration, since Palestinian and Israeli patients who are admitted share the same rooms.

Also taking part in the Buenos Aires meeting was the group of "Clowns No Perecederos" (Non-perishable Clowns), made up of 50 artists, an organization founded during Argentina's severe economic crisis of 2001-2002.

"People felt guilty about laughing and also, because of the severity of the crisis, they couldn't go to shows because they had no money. That's when we decided to put on shows where the price of a ticket would be some non-perishable food item that would be donated to children's dining rooms. That way people could laugh guilt-free," Cristina Marti, founder of Non-perishable Clowns, told EFE.

The artist, who trains clowns, said that "getting laughs, causing pleasure is very healthy", but added that there are significant differences between ordinary clowns and hospital clowns.

"There are a lot of things a hospital clown cannot say or do, while an ordinary clown is allowed to do whatever he comes up with. He doesn't have so many things to be careful about as he would in front of a patient in a precarious state of health," Marti said. (IANS)