It is an auspicious year for Buchinger Wilhelmi’s two wellness clinics. The group’s German facility is celebrating its 70th anniversary, while its Spanish outpost will turn 50 in September. Buchinger Wilhelmi is the world’s largest privately-owned clinic dedicated to the science of therapeutic fasting. Around 6,000 guests, from more than 60 countries, check in each year.

Founded by Dr Otto Buchinger, a medical doctor, philosopher and pioneer of medical fasting, the clinics are now run by Leonard and Victor Wilhelmi, Buchinger’s great-grandsons. Leo, aged 35, runs the German clinic; Victor, 37, manages the Marbella base. Their mother, Dr. Françoise Wilhelmi de Toledo, is in charge of the scientific elements of both clinics.

“In a world that is spinning faster and faster to the point of derailing, we want to be a safe haven for those who wish to regenerate and get in touch with themselves,” says Leonard.

The clinic’s extensive teams comprise doctors and therapists, who span an array of specialisms from fasting to medicine to nutrition to diabetology, and an array of massage therapists, counsellors, nutritionists and personal trainers.

Last year, I visited Buchinger Wilhelmi’s German facility, which overlooks Lake Constance in Überlingen. I booked to follow its 12-day fasting programme and was so impressed by the results that I arranged to visit the sister clinic in Marbella for 10 days earlier this year. Having fasted on my previous visit, I was keen to try Buchinger Wilhelmi’s calorie-controlled, high-nutrition diet. My personal Buchinger doctor suggested I try a diet of 1,200 calories a day. At this level, I would enjoy the benefit of weight loss while enjoying three delicious meals a day, most of which are made from ingredients supplied from within a 30km radius. I ended up having some of the best food I have ever eaten, anywhere.

Buchinger Wilhelmi Marbella, founded in 1973, is nestled between the Sierra Blanca mountains and the Mediterranean Sea. After gliding up the white marble steps, you enter a space that has the serenity of a monastery, the luxury of a five-star hotel and the efficiency of a top-grade medical facility. There is a hushed, almost meditative, atmosphere.

The main building is a classic Spanish-style hacienda, flowers tumbling from balconies above terracotta arches. There are three buildings that house the bedrooms and therapy rooms. My bedroom suite is more luxury hotel than medical clinic, with exceptional views from a private balcony towards Marbella and the sea. The only clue that you are in fact in a clinic are the bedside emergency bells to call the nurse and the four types of brightly-coloured bottled therapeutic water. Unsurprisingly, there is no minibar.

While this is definitely not a boot camp, there are a few rules. No smoking. No mobile phones in public areas. No children, no animals, no loud music. You don’t have to sign up for activities, but, if you are in the mood, you can choose between yoga, Pilates, Qi Gong, gymnastics, water aerobics, tennis, art therapy, cooking classes and regular informative talks on all subjects relating to health. Every evening, there is some kind of entertainment. There are also daily excursions to the beach and Marbella Old Town.

Before starting any therapies or diets, each guest has a blood test, which is analysed, and then a consultation with a designated personal doctor and, together, you devise a plan. My doctor advised hydrotherapy massage for low blood pressure and, to help combat my extensive list of allergies, colonic irrigation and acupuncture. To assist with poor circulation and water retention, I was booked on a course of lymphatic drainage massages.

Food-wise, you can choose between a low-calorie, seasonal and organic diet, intermittent fasting, or full fasting (depending on the length of your stay). Fasting is a three-dimensional experience; physical, spiritual and inspirational. Every religion uses fasting to prepare for an event, during which they typically assemble their communities for a spiritual practice. Buchinger Wilhelmi doesn’t have a religious colouring but it does use the metabolic state to enhance life. During fasting, sensitivity to and appreciation of nature, books, music and smell is enhanced and more accessible.

With 70 years of clinical experience and 20 years of medical data points from which to draw, Buchinger Wilhelmi has published hundreds of studies that look at the science of fasting. Indeed, the Wilhelmi family has invited professors from Ivy League universities to visit their clinics and, in collaboration with the institutions, has produced numerous papers and scientific journals.

Fasting, says Buchinger Wilhelmi, is proven to stimulate autophagy and detox enzymes, resulting in a deep cleansing of cells and tissue. At the same time, fasting reduces cholesterol and inflammatory processes, alleviates pain and improves mobility. Fasting can promote weight loss, reducing the risk of Type 2 diabetes by improving insulin sensitivity. Buchinger Wilhelmi also believes that fasting can improve brain function, protect against age-related cognitive decline, and even extend human lifespan – as has already been proven in animal studies.

“Fasting is the most powerful nonpharmacological and non-invasive intervention in the medical world,” says Dr Wilhelmi de Toledo, who believes that fasting can also ‘de-block’ certain traumas that we often plaster over with alcohol, nicotine, food and other drugs.

In 2023, Buchinger Wilhelmi Marbella witnessed the length of average stays increase from around 10 days to more than 14 days, although there are some guests that book in for over 40 days. A high percentage of guests return annually, some twice a year, and many come on their own, it being the perfect place to unwind in insolation, keeping yourself to yourself. One therapist told me that she is now working with the grandchildren of one of her first clients.

This is a family-run business that really does foster a sense of community. The staff, some of whom have been working here for 30 or 40 years, all confess to a deep attachment to the place. You can see affection in the positive atmosphere that pervades the clinic. It shows in the quality of the food and it spills over into the therapy rooms.

As I checked in, full of the stresses of everyday life, I witnessed outgoing guests hugging staff. When it was time for me to leave, clear-headed and much better equipped to deal with those stresses, I ended up hugging everyone I had met.

Now, when was the last time you did that on checking out of a hotel?

10-day fasting programmes from £8,340 per person; non-fasting stays are available from £218 per night, visit buchinger-wilhelmi.com

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