Peptan Blog



09 Apr 2024

Unlock the potential of intermittent fasting for both body and mind with insights from renowned lifestyle-focused physician Jerk W. Langer, M.D. In his latest book, ‘Fasting without hunger’ (‘Faste uden sult’ in Danish), Langer delves into the science behind intermittent fasting, its benefits, and practical tips for getting started.

What is intermittent fasting?

‘It’s quite simple: the definition of intermittent fasting is having an eating window and a fasting window. One common method is the 16/8 approach: eating in an 8-hour slot and fasting for 16 hours without any caloric intake. For many, this just means skipping breakfast: morning can be a hectic time, with work, rushing kids off to school, and more, so skipping breakfast is the easiest choice. This means your eating window, from lunch to evening, is about eight hours.’ 

What are the benefits of intermittent fasting?

‘From all my research and experience, the answer is simple: you just feel better. If we look at the brain chemistry of a person who starts intermittent fasting, we see a metabolic shift. If you don’t eat in the morning, that means there’s no sugar, so your body doesn’t use it to burn energy. Instead, it uses fat, while the brain and heart use ketones – an alternative fuel the body creates when glucose isn’t available. When the brain uses ketones, they have a stimulating effect. That’s what so many people experience through intermittent fasting. I spoke to one famous Danish writer who was writing a novel: she told me she was more creative when she switched to intermittent fasting. 

‘As well as the mental boost, we see a physical shift too. Consuming fewer calories can be better for health and weight loss. And, of course, fasting is not a new thing. Followers of the world’s major religions throughout history have all practiced fasting, and in ‘pre-scientific times’ it was widely considered a beneficial treatment. The benefits must have been clear to our ancestors, too.’  

More on ‘Fasting without hunger’ (‘Faste uden sult’) 

Drawing from scientific research and client experience, Jerk Langer’s latest book offers a fresh perspective on the diverse benefits of intermittent fasting. Whether you’re seeking increased energy, more effective weight management, or improved overall health, this guide explores the possibilities of intermittent fasting. It includes personal success stories and delicious anti-inflammatory recipes too. ‘Faste uden sult’, written by Jerk W. Langer. Published by POLITIKENS FORLAG 

What are the challenges of intermittent fasting? 

‘The big elephant in the room is hunger. In one survey, people said they fear hunger more than almost anything! Going without food in the morning can be unbelievable. But I can tell you, from experience, that it’s always much easier than you fear.  

‘In the first week of starting intermittent fasting, your appetite hormones might make you feel hungry. You can tackle this by either diving straight into skipping breakfast altogether, or gradually reducing your eating window by 30 minutes at a time. The book suggests using distraction techniques to overcome hunger, as hunger pangs usually last only 2-3 minutes. It’s like adjusting to a new time zone – initially, you might feel disoriented and hungry, but after about a week, your body gets used to it.’ 

How can I get started with intermittent fasting? 

‘Of course, if you try it and you don’t like it, just start eating breakfast again. As I always say, the most important thing is eating healthy food – fasting can just be an extra tool in the toolbox. I always stress that intermittent fasting is not necessary, or even suitable, for everyone. It’s just one more option that I suggest, and that needs to be balanced with a healthy, nutritious diet. If it sounds like something you would like to try, here are some suggestions:  

  • Slow down your eating pace: 

It takes about 20 minutes for your brain to register fullness. Eating quickly could lead you to consume more than you need before you’ve had the time to realize you’re satisfied. Avoid overloading yourself with too much food; you can still feel satisfied with smaller portions.  

  • Follow an anti-inflammatory diet: 

Whether fasting or not, the best way for most of us to eat is through what I call an anti-inflammatory diet. It’s similar to the Mediterranean diet, full of plant-based foods and fish for essential omega-3 fatty acids. However, it’s worth noting what I call the “collagen paradox” – the healthier your diet gets, like with an anti-inflammatory plant-based diet, the less collagen you consume through your food, because collagen comes from animal sources. That’s where the potential need for supplementation comes in. 

  • Remember, intermittent fasting isn’t a short-term diet, but a lifestyle change:  

It’s not about strict calorie counting or temporary dieting, but rather about consistently eating healthily every day. That is what can help you to prevent the weight regain commonly seen with traditional diets. It’s a sustainable, human approach to health, not a cycle of yo-yo dieting.’ 

How do collagen peptides support intermittent fasting?  

‘One thing that people find tricky with intermittent fasting is how it relates to their workout and exercise routine. In reality, fasting has the best results if combined with exercise.  

‘When combining intermittent fasting with exercise and a healthy diet, which I often suggest, it’s important that the body gets the nutrients it needs to stay fit and prevent injuries. Here, the “collagen paradox” I mentioned earlier comes in, meaning the body might not be getting the collagen it needs. This is why I often suggest taking collagen peptides to supplement a healthy diet, which help to support the key structures in our body like connective tissues, bones, joints, cartilage, muscles, and ligaments – letting us stay physically fit, get the full gain from fasting, and live a healthy lifestyle.’ 

Any final thoughts on your own experience with intermittent fasting? 

‘Now that intermittent fasting has been part of my lifestyle for a while, I don’t even check the clock anymore. I’m not strict about it—I’m no saint, and nobody needs to be. If I feel like indulging in some red wine or ice cream, or if I’m out with friends and want to extend my eating window, I go for it. It’s all about balance, following the 90% rule—most of the time, I make reasonable choices, and then about 10% of the time, I allow myself to indulge and just enjoy being human. There’s always room for fun and spontaneity.’ 

About Jerk W. Langer 

Jerk W. Langer is a lifestyle-focused physician, public speaker, and science communicator, based in Copenhagen, Denmark. Jerk is a lecturer at the University of Copenhagen, Faculty of Health and Medical Sciences, as well as in postgraduate education for general practitioners. 

Recent articles

75 items

24 Apr 2024


In weightlifting, where every ounce of strength counts and the margin for error is slim, athletes are pushed to their limits. How do they succeed? We spoke with weightlifting phenomenon, Olympic hopef...

15 Apr 2024


Meet Danielle Gommers-Vriezema, a Dutch former Olympic judoka, who now coaches the Netherlands’ visually impaired (VI) judo team. Equipped with a degree in Nutrition & Dietetics, certifications in l...

13 Mar 2024


Paula Ellis (@paulaellisfit) is a specialist in the core pillars of a healthy lifestyle—nutrition, training, and psychology. She’s also an influencer, nutrition expert, and Key Account Manager at ...

15 Feb 2024


At Rousselot’s ‘On the Road to Win’ event, Nick Morgan, Managing Director and Consultant at Nutrition Integrated, shared valuable insights into the growing sports nutrition market and the exci...


15 Dec 2023


What do some of the leaders in the field of physical activity and health say about the benefits of taking collagen peptides supplements? Check this recent Spanish podcast with Dr. Alberto Sacristán (...

10 Nov 2023


In the second part of our interview with mobility expert Jerk W. Langer, MD (@jerk.w.langer), Jerk offers insight into the power of exercise, the benefits of collagen peptides, and ‘the collagen par...