The first relief: there is coffee. The cave-dwellers inspiring the version of the paleo regime on offer at Hotel Ola, a stone’s throw from Split airport, clearly needed their morning pick-me-up as much as I do. Also, they obviously appreciated a modest glass of wine now and again, which is surely fair, given that grapes can be hunter-gathered and fermented, can’t they?

As this might suggest, I’ve come to Croatia not because my body is a temple, but because it’s a two-up, two-down (with chunky ground-floor extension) in need of a little loving restoration. Some of the decor is a bit worse for wear, and the fuses keep blowing. Before long, this corporeal frame I call home will reach its half-century, and I’d rather it did so with its hinges oiled. Can a few days of a Mediterranean version of the paleo diet – in which carbs are reduced, proteins and healthy fats increased, processed food eschewed and fruit and vegetables abound – set me on the road to wellness?

To Trogir, then, a beautiful town on the Adriatic coast, both a Unesco world heritage site and, naturally, one of the filming locations for Game of Thrones, where it appears as Qarth, “greatest city that was or ever will be”. I’m not sure about that, but certainly the evening I spent wandering its labyrinth of narrow marble streets, all heaving with stalls, made me determined to return at greater length.

Hotel Ola is a short distance away, through the tiny settlement of Seget Donji, and each of its 50 rooms has a balcony with a direct sea view. Only open a few months, the hotel is quiet, spacious, immaculately clean and deeply soothing: the vibe is less frivolously indulgent spa than sophisticated battery-recharging station. Though this retreat is not one without its challenges …

Perhaps the greatest of these is the most innocuous sounding: the two-hour walk along the “Route of Health”, with its bucolic vineyards and olive groves. I should have been alerted to its rigours by the route’s other name, Napoleon’s Road (the French emperor annexed Dalmatia in the early 1800s); certainly the penny dropped once I looked up and saw a line of virtually unbroken verticality. Suffice to say that it took very much longer to ascend Mount Vlaska than it did to return to sea level – and I didn’t even get all the way to the top to the 13th-century church of St Elias. To make matters worse, my guide didn’t once break sweat or seem out of puff; but like everyone else I encountered during my stay he was unfailingly charming and patient. I particularly admired his tactful habit of pointing towards objects on the horizon to facilitate frequent rests.

Of course, I felt marvellous once it was over, and it had the additional advantage of making my other exercise sessions – early-morning yoga and gym-based training – look like a (flat, leisurely) walk in the park. Once again, the instructors could not have looked more kindly on me – one even encouraging my clearly fantastical dreams of completing a 10k run before I hit 50.

If I had less luck chatting to Ruzica Jukicic, Ola’s head chef, it wasn’t because of a lack of will and bonhomie on both our parts, but rather a language gap (she had more English than I had Croatian). But another staff member materialised to interpret, and so began my paleo/LCHF (low carb high fat) cookery lesson, which saw such unfamiliar ingredients as carob flour, psyllium, chia seeds and pickled samphire emerge as a variety of breads, puddings and delightful canapés.

The menu leans heavily towards the gluten free, but it’s more enjoyably viewed as an excellent use of local produce, including a herb and vegetable garden. Fish and seafood are particularly good, especially the “Trogir barrel” – sardines rolled in almonds and served on slivers of beef tongue and fresh tomato sauce – and the chargrilled octopus with baby broad beans and a homemade mayonnaise. Puddings, Dalmatian wine and a large terrace on which to eat and watch the boats go by sweep away any longing for chips.

Indeed, those in pursuit of a hair shirt would probably find Hotel Ola a little too easygoing, although there are more rigorous weight loss and detox programmes on offer. Nobody, after all, forced me to have a wonderful Decléor facial, or a full body scrub, or to sit by the rooftop pool reading my book and gazing at Croatia’s myriad pine-topped islands.

However, Hotel Ola presented a rather lovely reset, and I felt significantly better, more rested and even a little slimmer at the end of my five-day stint. Admittedly, I went from Split directly to Italy, where I attended a wedding of such epic largesse – and such monstrously delicious plates of carb-heavy pasta – that I returned to London too fat to do up my seat-belt on the plane.

But what are you going to do? Go to Tuscany and eat carob bread? The point is, as the healthy love telling you, it’s about adjusting your habits over a lifetime. And, a month or so on, I have. I now go to yoga and Pilates classes five times a week, swim regularly and eat more fish and vegetables. Chia seeds, not so much. But Rome wasn’t built in a day.

Way to go

The seven-night Paleo Programme at Hotel Ola costs from £1,710pp based on two sharing, including full board, flights, transfers, tailored paleo diet, lecture and consultation, two medical examinations, classes, treatments and massages
(thehealthyholidaycompany.co.uk)