Flying to Bangkok for nip-and-tuck surgery or an operation that can be done at a fraction of the cost back at home is becoming old hat. India, Malaysia and Singapore are also promoting so-called medical tourism. Bangkok is in front in terms of patient numbers. Market leader Bumrungrad claims to be the world's busiest international hospital, with 400,000 foreign admissions last year. Mind you, I'm not complaining about having high-quality medical care on my doorstep. When I got a fish bone stuck in my throat this year, Bumrungrad hospital did a fine job of removing the offending object. My private room was better than some hotels I've stayed in during my travels in Asia. But a more tantalising glimpse of medical progress can be found across town at Bangkok Hospital's new heart centre. Not only do their American-educated cardiac surgeons have access to the latest technology and training, they offer something out of the ordinary: stem-cell therapy. The procedure uses stem cells grown from samples of the patient's blood, which are processed at a laboratory in Israel and flown back to Bangkok. The cells are then injected into the patient's heart. It is an experimental technique that is only performed in a few countries, and is usually offered to patients with severe heart failure, whose only alternative is a transplant. Stem cells are controversial, not only in the US, where there are strict limits on their use, but also in South Korea, where test results have been faked, discrediting claims in favour of stem-cell therapy. Bangkok Hospital, however, doesn't use embryonic cells, which generate the most controversy from campaigners who say embryos are human life. It is hard to see what is wrong with using your own blood to grow cells that have the potential to become blood vessels or other body parts. Scientists in Asia seem to have far fewer qualms about dabbling with the building blocks of human life than their counterparts in the United States, where science has become increasingly politicised under the influence of Republican-leaning Christians. Thailand considers itself a religious nation of mostly Buddhist worshippers, but theology doesn't interject in scientific practice. Over the past year, Bangkok Hospital has successfully treated more than 40 patients using stem-cell therapy - mostly Americans willing to travel overseas for a procedure that isn't licensed at home. It is a far cry from mainstream medical tourism, but another side to Bangkok's sophisticated health sector.