Research confirms what I myself—and hundreds of my fasting course participants over the years—have experienced firsthand: that just one week of fasting opens up an extraordinary and deeply well-being–enhancing space, where the body is given the best possible conditions to heal, recover, detoxify, and strengthen our energy levels, gut flora, brain health—and overall well-being.

I can still remember that morning by the North Sea as if it were yesterday. I was 19 years old, a student at Gerlev Sports Academy, taking part in a health-pedagogical programme aimed at building bridges between Eastern and Western body culture, philosophy, and nutrition. As part of the programme, we were to undertake a 10-day fasting retreat.

I thought: “Honestly, Helen, how on earth are you going to get through this?” Mostly because of the asthmatic bronchitis that had followed me throughout my life up to that point, bringing with it constant coughing, mucus, fever, and a breath that never quite seemed sufficient.

But how wrong I was! Already on the third day of the fast, something happened that I would still describe today as one of the most extraordinary experiences of my life. I woke up and suddenly I could breathe freely. Completely freely. No coughing, no mucus, and no constant struggle for air. I rushed down to the sea, and everything felt brighter that morning—the air, the sky, the colors, my mind. And my body, which for the first time felt alive and light.

It was so powerful that I knew I would never be able to let this go again.

A faithful companion throughout life

Since that day, fasting has followed me as a faithful companion—both in my own life and alongside the thousands of course participants I have taught through my fasting courses for nearly 40 years.

I fast myself several times a year, and for me it is a way to reset both body and mind. When I’ve had busy periods, when my memory feels foggy, or when I can sense my energy is flat, I know that a week of fasting gives it all back to me—and more. And I hear the same from my course participants again and again.

As one of them once wrote to me: “I cycled home feeling newborn and high—and just so happy.”

Using a true “Gen Z” expression, I would describe fasting as an amazing piece of next-level self-leadership. Because when we fast, we get to know the body and all its cells. We experience the deep connection between diet, body, and mind—between the gut and brain health—and we discover that we can do more with less. That we don’t need to eat all the time to have energy.

Many of my course participants describe discovering new layers within themselves. As one participant once wrote to me in their feedback: “I went in curious—and came out with something far deeper than just knowledge about fasting.” Another wrote in the same vein: “In this one week, I’ve learned more about the connection between diet, body, and mind than I have from reading countless books over the past five years.”

But why does fasting do us so profoundly good?

The short answer: because we give the body a break. A break from the constant work of digesting, breaking down, and processing everything we put into it. When the body is given rest, it begins to repair itself.

After three days, the body shifts from sugar metabolism to fat metabolism. The liver begins releasing ketones, which travel to the brain and help repair synapses. Tissue repairs itself, connective tissue releases tension, and the body feels lighter and more supple. Many course participants describe how old joint pains ease and energy returns. As one put it: “I feel joints that suddenly move without pain. My brain has had quiet pauses—completely free of background noise.”

And research confirms it. A major study from Queen Mary University of London (2024) followed 12 healthy participants who fasted for seven days. The researchers took daily blood samples and observed how the body shifted gears. After just two days, participants began using fat stores for energy—but the most striking changes occurred after three days. At that point, blood proteins changed significantly across the entire body—from the brain to the major organs. This revealed a whole-body response that supports the health of all the body’s major organs (Source: Queen Mary University of London – link to the study here).

A fasting program can also do something else remarkable—if you at the same time make sure to create an alkaline surplus in the body, for example through vegetable juices and broth, as participants in my fasting courses receive. Most of us carry an excess of acid stored in our muscles and tissues. This makes us tired and stiff, and eventually the body has to draw calcium from bones and teeth to neutralize the acid. When the body is supplied with alkaline elements during fasting, it can eliminate the acid through urine, skin, stool, and breath. The result is that we feel lighter, stronger, more mobile, and more energized.

And the effects of fasting don’t stop at the physical level. Body and mind are closely connected—and when we fast, processes are set in motion on both planes. In our fat stores, we don’t only keep energy, but also stored memories: trauma, grief, stress, and heavy experiences. When we burn fat, we gain the opportunity to let go of these as well. Psychologically, this is healing because we release accumulations that often build up during busy, stressful periods. That’s why many people experience becoming clearer, happier, and freer.

A holistic experience—for body, mind, and consciousness

There are many ways to fast—but in my course Fast dig fri – find ind til din kerne, which I have developed and refined over four decades, you are offered a holistic experience that speaks to the whole human being—body, mind, and consciousness. The course is grounded in my experience as a psychologist, yoga teacher, mindfulness instructor, my training in functional medicine, and my own 40 years of fasting practice. This allows me to combine knowledge of the body and nutrition with deep insight into the psyche, so participants gain both a powerful physical experience and a deeper health-psychological understanding of what unfolds along the way.

During the courses, we fast on organic vegetable juices, herbal teas, and broths that give the body the best possible conditions to eliminate toxins and regain balance. Each day includes gentle yoga, meditation, relaxation, massage, and foot baths—and several times a day I give health-psychological talks that provide participants with insight into how fasting affects the body’s physiology, psychology, and overall well-being. The structure is firm, but the atmosphere is caring, which means that most participants experience energy, calm, and clarity rather than hunger.

And then there are the surroundings. My fasting courses are held at Eriksen Instituttet, my own newly renovated place, Skovgården, set in beautiful natural surroundings on the island of Als—right next to Denmark’s longest coastal forest, Nørreskoven, and close to the sea. Here, there is space, calm, silence, and a natural setting that in itself supports the processes participants go through. Many experience truly slowing down, releasing stress, and recharging their batteries—with self-insight, joy, and energy that extend far beyond the five days we spend together.

Read more about my fasting courses—and see what my past participants have to say about them

Sources: Study identifies multi-organ response to seven days without food