A tan and a few souvenirs were the most people used to bring back from a beachside holiday in an exotic overseas locale. Now, it's possible to come back through customs with a new set of boobs or a new hip. Medical tourism is a rapidly growing industry, especially in Asia and South America, where many Westerners now travel for a range of health treatments, from simple elective cosmetic procedures like teeth whitening to major and potentially life-saving surgeries like organ transplants. Even rehabilitation from drug and alcohol addiction can be done offshore - The Cabin, a luxury rehab in Chang Mai, Thailand, is popular with Australians, and boasts rocker and Kate Moss-ex Pete Doherty as a former client.

The less-discussed cousin of medical tourism is 'wellness' tourism - the health retreats and alternative therapies that can also find a market with tourists looking for physical and spiritual renewal rather than just cocktails and room service on their holiday. While most wellness tourism consists of pretty benign practices that will probably leave guests feeling amazing as they board the plane home - an organic diet for a week, some yoga, some remedial massage - others involve treatments that skirt the boundaries between a wellness treatment and a medical treatment, such as extreme detoxes, enemas, supplement and hormone regimes, laser skin treatments, or acupuncture.  

There's nothing inherently wrong with medical and wellness tourism. These kinds of experiences can be a win-win for both Western guests and local economies. Who wouldn't prefer a high quality of care at a decent price and the chance to recover in a luxury suite in a tropical paradise? Especially when it's compared to the long-waiting lists, cramped wards and miserable food that many people experience in their local public hospitals.

Plus, there's a definite possibility of positive impact on local economies in developing countries - less 'brain drain' of doctors and nurses overseas, improved quality of local hospitals, more jobs opportunities for local young people who can seek careers in medical and wellness industries, and increased spending in general within the tourist economy, as medical and wellness tourists often also eat, drink, sightsee and shop just like regular tourists.

But there are a number of concerns raised by the rapid rise of this global industry. In general, the globalisation of health care can intensify inequalities both in sending and destination countries. It may mean that those who can afford to travel overseas for treatment do, decreasing the motivation for public investment into local health systems for the rest of us. It can also mean increased disparities at medical tourism destination sites, if the best quality staff and treatment centres become exclusively 'foreigners only' or simply far too expensive for local patients.

Regulations around health and medicine also differ around the world, often leaving a worrying legal and ethical grey area when people cross borders for treatments they can't access at home. Commercial surrogacy for example, and sex-selection through IVF, where parents can screen embryos to choose a son or a daughter, are both banned in Australia, prompting people to seek these reproductive options overseas in countries like India and Thailand. This has led to tragic cases like Baby Gammy, who made headlines last year. Debate still rages on 'reproductive' tourism, especially international surrogacy. It undoubtedly provides parents with the children they so desperately want, but are the costs and risks for the locals involved too high?  

Even with 'wellness' treatments, which are usually far less invasive than traditional medical treatments, regulatory frameworks for the training of therapists, hygiene standards and the use of potentially harmful ingredients in treatments can be patchy or even non-existent depending on the context, leaving clients open to injuries, infections and allergic or toxic reactions. Something as simple as a spa pedicure can leave you open to an incurable infection like Hepatitis C, and though this can also happen in salons right here in Australia, the prevalence of hepatitis and therefore the infection risk is far greater in many of our favourite Asia-Pacific holiday destinations.

So where does this leave all of us who are thinking about a detox retreat or a little nip and tuck the next time we book a trip overseas? Like any decision about your health, the answer is research, research, research. Medical and wellness treatments overseas can be affordable and provide fantastic quality (often even better than at home). But the potential health and legal risks have to be thought through.

Are the 'all- natural' diet supplements you stocked up on in Peru legal to bring back into Australia? Will your health insurance cover any complications that arise back in Australia after your cosmetic surgery in Thailand? What kind of training and hygiene standards does the salon doing your Botox in Bali adhere to? And on top of these questions about your personal safety are the big questions about whether you can be an ethical or sustainable medical tourist - what will the impact of your trip be on the local people at your destination, and on the equity of health care globally?