A number of Asian countries, among them India, Malaysia, Singapore and Thailand, are making big bucks from the rapidly growing market for medical tourism, which may be worth US$100 billion a year by 2015.
Some government health services have even begun to go into the business of arranging medical travel for their own nationals to get them more cheaply and quickly in another country.
Costs of treatment are a powerful draw. A heart bypass operation costs US$113,000 in the US, but only US$10,000 in India, US$13,000 in Thailand and just US$3,250 in Mexico. A hip or knee replacement is about US$48,000 in the US, but less than a quarter of that price in India, Thailand, Malaysia, Singapore or Poland.
With such low prices, many patients must be tempted to get on the next flight for a new hip or heart. But medical tourists should look before they leap.
Japanese clinical academic Professor Mikako Hayashi warned this month that medicine needs to move away from a curative model, which gives immense power and profits to special interests and big drug companies, towards a healthier and cheaper preventative regime.
"Government and business leaders should be more aware of the economic boost that can come from healthy workers," Hayashi said. "National health systems are going broke and crippling countries with debt because they have a stupid business model.
"I tremble when I look at the United States. They spend more, and yet Americans are less healthy than people in other developed countries. Their system is twisted to benefit the rich and powerful, but that comes at a tremendous cost to the economy and society as a whole."
Recent figures show that the US spends US$2.6 trillion a year on health care - 17.6 per cent of its gross domestic product, or US$8,233 per capita. Other rich countries typically spend about 9-11 per cent of GDP. Yet by any measure - whether life expectancy, infant mortality or deaths from disease - Americans are less healthy. Japan, with health spending of 9.5 per cent, has the healthiest, longest-living people.
Jill Hodges, lead editor of a recent book entitled Risks and Challenges in Medical Tourism, notes that people travel abroad for medical treatment for a variety of reasons, not just for cheaper operations.
"Medical tourists travel from the US to central and South America for affordable treatments, from the UK to India for shorter waits, from Nigeria to Europe for quality services."
But she may be whistling in the dark with her hopes that sending patients for cheaper bariatric surgery in Colombia or cancer treatment in Singapore "could reduce our overall health care tab, and that global competition potentially could encourage greater efficiency in the US".
The US suffers from the strong grip of huge but inefficient health insurance companies and powerful medical interests, which have raised spending, but caused millions of poor Americans to fall through the health safety net. The power of the medical lobbies was seen in debates over President Barack Obama's efforts to bring affordable health care to ordinary Americans.
There is no doubt about the growing scale of medical tourism, but much dispute about the hard numbers. Hodges writes of "hundreds of thousands of individuals travelling to and from every continent for care every year" and puts the value of the business at US$20 billion to US$35 billion. German professor Helmut Wachowiak says it is worth up to US$60 billion and is growing at 20 per cent a year.
That does not include the costs of flights or other expenses in going for treatment. The growing business of medical tourism has even spawned a website, mymedholiday.com 
The business is so big and booming that the Organisation for Economic Co-operation and Development recently published a 55-page review of it.
It said: "Whilst there is an increasing amount written on the subject of medical tourism, such material is hardly ever evidence based," adding that "We can narrow down the numbers of medical tourists worldwide as lying somewhere between 60,000 and 50 million!"
The OECD showed that many common medical operations cost as little as 10 per cent to 25 per cent of US prices in India, Thailand, Singapore, Mexico and Poland. It said cheap flights and the explosion of information via the internet are helping to promote medical tourism. But there should also be a health warning attached to medical travel.
Its promoters include not only doctors and hospitals in host countries, but websites, insurance companies, brokers, financial services firms, travel and hospitality services companies, the media and the advertising business.
Unlike in a patient's home country, where doctors or a health service function as gatekeepers, patients going abroad normally have to take decisions via the internet without a chance to check outcomes or infection rates. Medical tourism providers get paid for performing their services, not for improving health.
The best medical tourism providers are excellent, such as the Bumrungrad or St Louis in Thailand, or Raffles in Singapore, but the quality of others varies.
The OECD report tries to establish a common platform on which standards and regulations may be based, not least to ensure that patients' treatments can be checked and spread of disease and hazardous micro-organisms prevented. But its report concludes that "there is a pressing need to explore further as to whether medical tourism is virus, symptom or cure".