It’s difficult to know how to categorise Mayrlife. Is it a hotel? Well, it certainly has beautiful rooms in a picturesque location. But to stop there would be to considerably undersell the property. Is it a wellness retreat? There are yoga classes and a gorgeous spa. But the offering is also about as far removed from anything as woo-woo as crystal healing as I can imagine. Is it a medical clinic? The place is staffed by doctors and specialist practitioners. But you definitely don’t have to be sick to get a lot out of a stay here.

On its own website, Mayrlife calls itself variously a ‘medical spa’ and ‘medical retreat’, and promises a ‘transformative journey to optimised living and longevity’. This could mean many things, but, at Mayrlife, it means an incredibly tailored approach to achieving optimal gut and digestive health – and, as a consequence, improving and extending overall health and longevity. Rebel Wilson is a vocal fan, visiting numerous times during her recent weight loss journey, while Kendall Jenner also recently popped in for a post-Paris Fashion Week pick-me-up.

Based on the work of Dr F.X. Mayr, Mayrlife teaches the principles of Modern Mayr Medicine: a science-based approach to health that encompasses detox, nutrition, and lifestyle changes, and aims to give guests a blueprint for sustainable long-term healthy living, long after they’ve returned home. The first step on this journey is to visit the clinic in Austria to experience ‘the cure’ – an intense 7-10 day fasting gut cleanse, complemented by tailored treatments, tests and plenty of downtime – with the idea being that guests leave with a fully reset digestive system, a flourishing gut microbiome, and armed with enough information about both themselves and the Mayr method to keep it up at home.

It also means rules. Lots of rules. While my shorter four-day stay doesn’t allow for the full Mayrlife gut cleanse – a process that involves, among other things, carefully timed laxatives that take at least a week to do their thing – I am still warned to prepare in advance for what is to come. A week before arrival a set of instructions lands in my inbox highly recommending that, to ease myself in before the cure proper, I should abstain from caffeine, sugar and alcohol, drink at least two litres of water a day, and get at least eight hours of sleep per night. So far, so sensible. Then things get a little tricker: eat little or no dinner, and no raw foods after 4pm. Considering I’m someone with a schedule that means at least twice a week I don’t eat until well past 10pm, this was going to be trying.

Having been given little context for these instructions but trusting the process, a week later, cure prep (more or less) achieved, I arrive in Altaussee and receive my first induction into Mayr medicine. The no dinner thing? Our modern habit of skipping breakfast and then eating large meals in the evening is terrible for the digestive system, which should be resting and rejuvenating overnight, not trying desperately to break down a steak and a glass of red wine when your body needs calories least. Likewise with raw foods: they’re difficult to digest and, if eaten too late, will simply sit in the digestive system fermenting, leading to bloating and gastric distress. In other words, stop having salad for dinner.

Perhaps somewhat counterintuitively for a clinic that offers a fasting cleanse, food is incredibly important at Mayrlife. Tailored nutrition plans are ‘prescribed’ by the team of doctors, so my next port of call is a consultation that will, among other things, decide how, when and what I eat during my time here.

My personal physician, medical director Dr. Melanie Gatt, is a bright, bubbly and extremely healthy-looking woman who could be the poster girl for converting to a Mayr lifestyle. Being in my mid-30s with no major health complaints to speak of, our consultation is fairly straightforward: I am quizzed about my lifestyle and eating habits, measured, weighed, have my heart rate and blood pressure taken and undergo myodiagnostic testing for all the major intolerances. This manual form of intolerance testing sees powder forms of different common aggravators placed on the tongue to trigger muscular responses, which are measured by pushing your arm or leg against the tester's’ Muscles stayed nice and strong? You’re all good. Found yourself with a limp noodle for a bicep? You’ve got some dietary changes to make.

I escape relatively lightly with intolerances to white flour and peanuts – both of which I’m informed can be corrected by abstaining for six months. Being a generally active person, I’m also put on the most lenient of meal plans, which at Mayrlife are graded from 0 (essentially three soups a day) to 2 (more substantial meals for breakfast and lunch, soup for dinner). Regardless of your grade, calorie restriction is a given. The aim is not weight loss – although for many it’s a happy side effect – but rather to induce periods of hunger, as this is when the gut is able to focus on repairing itself rather than digesting food.

Given all this, I probably don’t need to tell you that the restaurant here is unlike any other hotel restaurant I’ve ever visited. A beautiful light-filled space with vast windows overlooking the manicured grounds and lake beyond, the first thing I notice is the quiet. No chatter of happy diners, no clinking of glasses, no music. The latter is true throughout Mayrlife; you won’t hear any muzak in the lifts or whale song while you’re getting a massage, and there’s a strict ban on taking phone calls in any communal spaces. It could be eerie but, with the chatter of birdsong in the distance, is in fact wonderfully peaceful.

Back in the restaurant I’m shown to my assigned seat, where I’ll be expected to return for all my meals. Each guest is given a number, clipped to a basket in which to keep your various mealtime supplements, which staff use to look up your specific dietary requirements. Don’t, I am (half-jokingly) warned during induction, try to bribe the staff into giving you banned items – they’ve seen it all and they will not have it.

Meals come with yet another set of instructions. No water 30 minutes before or after eating (it dilutes the stomach acids); keep talk to a minimum, take your time and focus on what you’re eating (hence the lack of music), and chew each mouthful at least 50 times (much, much harder than it sounds). It helps that the food is genuinely delicious and incredibly inventive, with head chef Stefan Mühlbacher devising ingenious ways to impart flavour into ingredients deliberately chosen for their monotony and easy digestibility.

Onions and garlic, universally banned for being common digestive irritants, are replaced with fennel and a naturally garlicky, omega-3 rich camelina oil. Meals are also dairy-free and low carb with a big emphasis on vegetables and soups; eggs are served at breakfast on alternate days only; and twice a day you’ll be given a ‘chew trainer’ – a deliberately hard roll made from quinoa, spelt, or other healthy grains designed to aid in the goal of 50 chews per mouthful.

Portions are small but, I’m told, follow the instructions, and you won’t feel hungry. I manage to stretch each meal out to around 45 minutes, giving my brain time to register what I’m eating, and miraculously it works. I find myself neither hungry nor experiencing cravings during my entire stay.

It helps, I suspect, that days are scheduled so as to leave little time to think about hunger. As well as treatments prescribed by your doctor, a weekly programme of classes, talks and workshops is available to every guest. Mornings begin with a light workout class, while guests are also encouraged to take a dip in, or a stroll around, the lake, explore the fairytale village of Altaussee, or join group activities including yoga, e-biking, paddleboarding, hiking, cooking classes, and evening lectures from the doctors.

Alternatively, a state-of-the-art spa features a salt water swimming pool and expansive array of saunas, steam rooms and infrared pods, while each guest is kept busy with a bespoke itinerary of treatments, tests and appointments designed to address their individual needs. During my stay I am variously sent for a detoxifying liver wrap and foot bath (slumber-inducing levels of relaxation), cryotherapy (decidedly less so), a massage (more sports therapy than Swedish), hypoxytraining (a form of altitude training that oxygenates the blood while lightly mimicking the effects of gas and air), a 3D body scan to assess my posture, and metabolic profiling. There’s also an appointment with the on-site nutritionist, who leaves me with a personalised 10-point plan for optimal meal distribution, recommendations for a more alkaline diet, instructions for managing cravings with bitter drops, and better alternatives to my usual protein and vitamin supplements.

Dinner is served strictly between 5.30pm and 7pm each evening so, while the gym and spa remain open after this, most guests are safely confined to their rooms by 8pm. It’s safe to say this is far from my usual holiday routine, but at Mayrlife this downtime comes as something of a relief. The routine here requires participants to take in a lot of information and, while nothing feels particularly arduous, it’s genuinely surprising how tiring a day of being poked and prodded at can be. Happily my room, with its light wood furnishings, cosy seating area, vast king-size bed, and private balcony overlooking the dramatic Alps beyond, is a lovely setting to which to retire for a sleep-inducing herbal tea and early bed time.

Which is all well and good – but does it work? In a word, yes. I started noticing both visible physical changes by day two, by day three my lower belly pooch, which I’d long put down to inevitable post-20s weight gain, had all but disappeared as my inflammation cleared up, and by the time I left it felt as if my entire body had deflated. I’ve now been home for nearly a month and, while not all aspects of the Mayr way of living are easy or practical for modern schedules, I’ve stuck to as much of it as I’ve found possible. I haven’t had caffeine for nearly a month, white flour and peanuts are firmly banned, and I’ve reorganised my meals so that I rarely eat dinner – and I’ve never felt better. I sleep well, I have more energy, I rarely feel bloated or uncomfortable and even my hangovers are noticeably less debilitating (well, we can’t be good all the time…).

Many clients discover Mayrlife when more traditional Western medicine fails them and, while they undoubtedly have much success in helping these patients, it’s almost the reverse of what the team here is trying to achieve. Don’t come to Mayrlife for a quick fix. They’re not interested in helping you lose a few stubborn pounds before a big event. They want to set you up with a long-term lifestyle that is just as much about prevention as it is cure. Consider me a convert.

Programmes start at €2,990 (approx. £2,570) and include all treatments and food, for a minimum duration of seven days. Rooms start from €460 (approx. £395) per night based on single occupancy. Visit mayrlife.com.

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