12 Intermittent Fasting Benefits Proven by Research

Dieser Artikel basiert auf wissenschaftlichen Studien

Intermittent Fasting | Keto | Benefits | Conclusion | FAQ | Research

After one of the intermittent fasting health benefits was awarded the Nobel Prize in Medicine, fasting has taken the world by storm.

Finally, intermittent fasting is socially acceptable. Therefore, one no longer gets strange views when refusing donuts in the break room. Pensioners try it, and doctors recommend it.

Also, the health benefits of intermittent fasting are proven by research. But how to apply intermittent fasting correctly to achieve those health benefits?

Are there different benefits that are especially suitable for your preferences and your individual daily life?

What Is Intermittent Fasting?

During intermittent fasting, you eat within a certain period; during the rest of the day, you don’t.

Various forms of intermittent fasting exist, but eating within about 8 hours is the most popular. Conversely, this means that during 16/8 intermittent fasting, you are not eating for 16 hours a day.

How It Works

During 16/8 intermittent fasting, you only eat between noon and 8 p.m. According to this, the body fasts for 16 hours, whereby 8 hours have already elapsed while sleeping.

Therefore, during the day, you have an 8-hour window in which you eat and one in which you don’t.

However, you can individually change the eating period as you wish. For example, you eat between 2 and 10 PM.

Nevertheless, I always tried to keep sleeping within the 16-hour fasting period. This way, only 8 hours of fasting are left during the daytime.

Moreover, your body, particularly the stomach and gut, can rest properly during this time.

Since you sleep 8 16 hours, you only have to skip breakfast and snacks. And Voila! Reaping the health benefits of intermittent fasting is that easy.

Although this one is very sticky, that you wouldn’t have enough energy for the day without breakfast is a myth disproven by research.

Because the body gives you a lot of stress and growth hormones in the morning, you quickly get enough energy for the day.

For this reason, our bodies wake us up in the morning. You will find more details about hormones in the health benefits of intermittent fasting.

intermittent fasting benefits

What to Eat and Drink

Whether it is proteins, carbohydrates, or fat, eating is prohibited during the 16-hour fasting period. Why?

Three processes in the body can break the fast. Each of the three macronutrients stimulates one of them: AMPK release.

However, drinking is allowed during intermittent fasting.

Therefore, you can drink the following drinks while intermittent fasting without the fear of breaking the fast:

  • Black tea
  • White tea
  • Green tea
  • Herbal tea (check for sweeteners/candied fruits)
  • Oolong tea
  • Black coffee
  • Black decaffeinated coffee
  • Diluted apple cider vinegar
  • Mineral water
  • Lemon water (a splash of lemon or lime)
  • Water with orange or cucumber slices

Although a splash of unsweetened almond milk does not always break the fast, I would advise against additives. You can find the relevant details in my ultimate guide to coffee on intermittent fasting.

Ketogenic Diet

For fast results, combine intermittent fasting with keto.

Because the process of fat burning – ketosis – is the same for both keto and intermittent fasting, they do well with one another.

Yes, you hear correctly. Despite rumors about its danger, ketosis is an entirely natural process in the human body that helps humanity survive.

Ketosis means nothing but that the body has broken down its carbohydrate stores and instead uses the stored body fat to produce energy.

In this sense, low-carb and mostly keto try to get fewer carbohydrates and proteins and more fat into your diet.

As a result, the storage hormone insulin is drastically lowered, which enables fat burning and prevents fat building.

Since the keto diet tries nothing else than to reap the same health benefits as intermittent fasting through nutrition, keto, and intermittent fasting do so well together.

Although you break the fast with a meal, you are still in ketosis due to the ketogenic diet and partially in fasting mode.

Therefore, the health benefits of intermittent fasting can be even more significant if you combine it with a ketogenic diet:

  • No side effects like headaches, stomach upset, keto flu
  • Sustainable energy and performance without switching between glucose and fat-burning
  • Better fat burning because you get ketosis faster through intermittent fasting

What Are the Benefits of Intermittent Fasting?

Nature has designed human beings to go for many days without food. Otherwise, humanity would not have survived harsh winters and food scarcities.

Accordingly, the world record for fasting is 382 days (Stewart et al. 19731).

Although we no longer have to do so in our world of abundance, indigenous peoples often do not eat for several days, even today.

Even if we no longer need fasting as a survival mechanism, we can benefit from the practical and health benefits of intermittent fasting:

1. It’s Damn Simple

Diet advice is more contradictory than ever before. One time you should eat less fat, then more. Once you do not eat carbohydrates, then you should feast on them. Some swear on vegetables, others on animal products. Who still has a clear view?

Intermittent fasting, however, is foolproof.

The classical 16/8 intermittent fasting only has two rules:

  • No breakfast
  • No snacks

That’s it. Health can be that simple.

Accordingly, you eat lunch at noon and dinner at 8 p.m. When thirsty, you drink (mineral) water, tea, or coffee without sugar, milk, or sweeteners during fasting.

That’s all you need to know – the simpler the rules, the better you can implement measures into your everyday life.

2. Intermittent Fasting Works Without Exercise

The first questions with diets are: Will it work? How much weight can you lose? How much exercise is necessary?

Fasting, on the other hand, is once again simple. After you eat nothing, energy must come from your energy storage. And as long as you don’t cheat and trigger an insulin reaction, the energy comes from stored body fat.

Furthermore, intermittent fasting can be increased anytime, which does not work with diets. If you follow a strict keto diet, you can hardly become more ketogenic.

Although there is a possibility!

And that is again fasting because the ultimate ketogenic diet uses only stored body fat for energy production. And that’s fasting.

Moreover, with fasting, you can still fast for a more extended period or more often, which means there are hardly any limits to the health benefits of intermittent fasting.

That is an unbelievable advantage of fasting over all diets out there.

Moreover, current studies prove intermittent fasting fights visceral fat more effectively than low-carb diets. And this without exercise (Catenacci et al. 20162).

3. It’s Cheap as Hell

Intermittent fasting is not only free, but you also make a profit. Think about the drastic decline in shopping costs and the elimination of snacks.

The food industry has hammered us with stupid ideas about health and weight loss over decades:

  • You have to eat six times a day
  • Snacks are healthy
  • Many meals a day boost metabolism

Although breakfast is the most important meal of the day for the food industry, it helps nobody else.

Furthermore, with intermittent fasting, you don’t have to hunt for organic meat or wild and carefully caught yellowfin tuna with as little mercury contamination as possible.

Moreover, “organic” does not always mean better because even in organic farming, you can still use the wrong feedstuff (i.e., grains for cattle).

Since you don’t have to buy a gym membership, expensive equipment, or outfits, this benefit of intermittent fasting will impact your bank account.

4. It Saves Tons of Time

The food industry loves nutritional advice associated with several meals a day. Why?

Although real home-cooked food is where you know what’s inside, its preparation takes time. Since no one can cook six times a day, you have to grab processed food when eating several times a day.

With intermittent fasting, however, you know what you are getting:

  • It’s simple, comfortable, and flexible
  • You don’t have to precook or portion
  • You don’t eat chemical additives you don’t know about

Fasting saves time because no time has to be spent on shopping, preparation, cooking, and cleaning up. Thus, it’s a great way to make your life easier.

Just skipping the unnecessary breakfast saves 30-45 minutes.

Moreover, it’s completely flexible. Accordingly, I often decide to skip lunch when I want to be incredibly productive.

Because, if we are honest with ourselves, lunch with all its opportunity costs burns about two hours. Also, you are more flexible when it comes to appointments and business trips:

  • Fast food avoided
  • Time and money saved
  • Productivity increased

5. Intermittent Fasting Induces Autophagy

Fasting activates autophagy, a cleansing mechanism that replaces dysfunctional cells with new ones and detoxifies the body.

Accordingly, autophagy activates the body’s self-healing power by removing harmful and toxic compounds and recycling damaged proteins.

Because this natural detox fights cancer, diabetes, liver, and autoimmune diseases, the discovery of autophagy was awarded the Nobel Prize in Physiology or Medicine in 2016 (Levine et al. 20173).

Since it also slows down the aging process, autophagy is probably one of the most significant health benefits of intermittent fasting.

6. It Improves Inflammation and Longevity

Like the reduction of carbohydrates, intermittent fasting brings good results in treating age-related diseases.

While a low-carb diet only reduces carbohydrates, intermittent fasting also reduces the consumption of proteins, which positively affects longevity in general.

With this in mind, most modern diseases, such as arteriosclerosis or type 2 diabetes, are characterized by excessive growth.

In addition to autophagy, reducing inflammation in the body enormously contributes to the anti-aging effect of fasting.

Ketosis during fasting lowers blood sugar and insulin levels, which reduces inflammation markers and free radicals that cause disease.

Accordingly, a current study named extended life expectancy a significant health benefit of intermittent fasting (Catterson et al. 20184).

7. Fasting Increases Lean Mass

Intermittent Fasting 16/8 is nothing new among bodybuilders. Accordingly, peak fasting, fasting for 14 to 18 hours daily, is an old and well-proven strategy for muscle building.

Also, bodybuilders train during this fasting period for the best results. Because contrary to conventional belief, intermittent fasting does not let the muscles atrophy.

When fasting, the body also wins energy from proteins. But those originate from damaged cells (autophagy), not from the muscle mass.

Moreover, the body releases growth hormones to ensure you don’t lose muscle during the fast. This way, the body protects lean and bone mass (Rudman et al. 19905).

Accordingly, proper intermittent fasting, combined with strength training, is one of the most effective natural growth hormone stimulators and helps build muscle (Ho et al. 19886).

8. Intermittent Fasting Boosts Your Metabolism

Contrary to conventional wisdom, intermittent fasting does not slow down metabolism.

Instead, research has proven that intermittent fasting increases the metabolic rate (Drenick et al. 19647).

Because fasting releases growth hormones and adrenalin, our ancestors could hunt for food without immediately feeling exhausted in times of food scarcity (Ho et al. 19888).

For this reason, they were able to ensure the survival of the species

Consequently, intermittent fasting increases the efficiency with which your body can utilize stored fat for energy.

9. You Can Fast on Any Diet

Although the advantages of intermittent fasting are even more effective with a low-carb diet such as the Keto diet, you can start intermittent fasting with any diet.

Since fasting isn’t a new method to learn but rather an omission, it takes less of you instead of more.

Since intermittent fasting is about not eating, you don’t need new recipes. On the contrary, you must choose which dish you won’t prepare today, regardless of your diet.

Therefore you can start intermittent fasting today if you:

  • Are a vegetarian
  • Eat animal products
  • Are lactose intolerant
  • Are on the road all day long
  • Don’t eat wheat
  • Are 90 years old
  • Are 17 years old
  • Can’t cook
  • Are a Michelin Star Chef
  • Are allergic to nuts

In short, nothing can stop you from fasting intermittently if you wish to.

10. You Can Do It Anytime and Anywhere

You do not need to be prepared for intermittent fasting. In short, you neither need knowledge nor preparation.

You don’t have to find your inner center to start fasting finally. You can do it anytime and anywhere by merely doing nothing.

As a beginner at intermittent fasting, you only need to decide to do it and have a glass of water or coffee now and then.

You can start right now to regain control over your health, especially since you don’t need any equipment.

Intermittent fasting is flexible and can be adapted to your occasion:

  • You can fast in the office and finish an annoying task today
  • If they serve garbage, you can fast on the plane
  • You can fast during vacation and therefore deviate from your diet plan more easily

11. Intermittent Fasting Benefits Gut Health

There is a reason why people with allergies and intolerances fancy intermittent fasting more and more.

Fasting periods allow your gut to rest. Therefore, fasting starves bad gut bacteria and reduces inflammation.

According to a current study, intermittent fasting substantially improves gut health and thus increases life span (Catterson et al. 20189).

12. Fasting Can Reduce Stress

In contrast to conventional belief, fasting does not cause more but less hassle.

And that also affects your cortisol levels. If a diet demands still more from an already stressed life, that does not contribute to relaxation.

Although you win time with intermittent fasting, you don’t need to fill these periods with more hassle. So you can start doing things for yourself, such as reading a book or discovering a new hobby.

Hence, that’s a benefit of intermittent fasting, which diets probably cannot offer.

The Bottom Line

Since health is a gigantic business strongly influenced by the pharmaceutical industry, we quickly reach for a pill when we suspect tiny ailments.

But sooner or later, every effect has one or the other side effect. So, the reactive treatment of possible symptoms with the chemical mace quickly leads to drug addiction.

Intermittent fasting, on the other hand, can help to reduce medication. Moreover, unlike drugs, intermittent fasting helps fight root causes instead of symptoms.

With this in mind, intermittent fasting can be a better alternative to swallowing pills for type 2 diabetics.

In contrast to diabetes drugs such as Metformin, intermittent fasting can also reduce the need for cholesterol- and blood pressure-lowering medication (Aly 201410).

Also, many people notice other improvements due to the wide range of intermittent fasting health benefits. These are, among others:

  • Mental focus
  • Improved sleep
  • Reduced acid reflux

Nevertheless, my experience is that intermittent fasting is, above all, amazingly flexible and straightforward. Hence, it saves time and money for more important matters.

Furthermore, I fast beyond 16 hours whenever it suits me. If I want to get things done, I skip lunch as well.

Accordingly, One Meal A Day (OMAD), another intermittent fasting schedule, brings even more flexibility and efficiency into my daily routines.

intermittent fasting for beginners book

Frequently Asked Questions (FAQ)

How often should you do intermittent fasting?

How often you fast is entirely up to you. Since intermittent fasting is amazingly flexible, you can do 16/8 the whole week, only during working days, or fast an entire day per week and eat on others.

Why Intermittent Fasting is bad?

The first few days might feel bad if you are used to a diet rich in sugar, but the health benefits of intermittent fasting are outstanding: Improved metabolism, lean mass, gut health, and blood lipid levels.

Is Intermittent Fasting Healthy?

The health benefits of intermittent fasting are incredible. Besides losing weight, fasting boosts metabolism and improves blood pressure, lipids, and life expectancy.

What happens to your body when you fast for 16 hours?

Besides the fact that the body can gradually burn more fat, intermittent fasting lowers insulin levels, which reduces the risk of diabetes and cardiovascular diseases.



1Stewart WK, Fleming LW. Features of a successful therapeutic fast of 382 days’ duration. Postgrad Med J. 1973 Mar;49(569):203-9. doi: 10.1136/pgmj.49.569.203. PubMed PMID: 4803438; PubMed Central PMCID: PMC2495396.

2Catenacci VA, Pan Z, Ostendorf D, Brannon S, Gozansky WS, Mattson MP, Martin B, MacLean PS, Melanson EL, Troy Donahoo W. A randomized pilot study comparing zero-calorie alternate-day fasting to daily caloric restriction in adults with obesity. Obesity (Silver Spring). 2016 Sep;24(9):1874-83. doi: 10.1002/oby.21581. PubMed PMID: 27569118; PubMed Central PMCID: PMC5042570.

3Levine B, Klionsky DJ. Autophagy wins the 2016 Nobel Prize in Physiology or Medicine: Breakthroughs in baker’s yeast fuel advances in biomedical research. Proc Natl Acad Sci U S A. 2017 Jan 10;114(2):201-205. doi: 10.1073/pnas.1619876114. Epub 2016 Dec 30. PubMed PMID: 28039434; PubMed Central PMCID: PMC5240711.

4Catterson JH, Khericha M, Dyson MC, Vincent AJ, Callard R, Haveron SM, Rajasingam A, Ahmad M, Partridge L. Short-Term, Intermittent Fasting Induces Long-Lasting Gut Health and TOR-Independent Lifespan Extension. Curr Biol. 2018 Jun 4;28(11):1714-1724.e4. doi: 10.1016/j.cub.2018.04.015. Epub 2018 May 17. PubMed PMID: 29779873; PubMed Central PMCID: PMC5988561.

5Rudman D, Feller AG, Nagraj HS, Gergans GA, Lalitha PY, Goldberg AF, Schlenker RA, Cohn L, Rudman IW, Mattson DE. Effects of human growth hormone in men over 60 years old. N Engl J Med. 1990 Jul 5;323(1):1-6. doi: 10.1056/NEJM199007053230101. PubMed PMID: 2355952.

6Ho KY, Veldhuis JD, Johnson ML, Furlanetto R, Evans WS, Alberti KG, Thorner MO. Fasting enhances growth hormone secretion and amplifies the complex rhythms of growth hormone secretion in man. J Clin Invest. 1988 Apr;81(4):968-75. doi: 10.1172/JCI113450. PubMed PMID: 3127426; PubMed Central PMCID: PMC329619.

7DRENICK EJ, SWENDSEID ME, BLAHD WH, TUTTLE SG. PROLONGED STARVATION AS TREATMENT FOR SEVERE OBESITY. JAMA. 1964 Jan 11;187:100-5. doi: 10.1001/jama.1964.03060150024006. PubMed PMID: 14066725.


8Ho KY, Veldhuis JD, Johnson ML, Furlanetto R, Evans WS, Alberti KG, Thorner MO. Fasting enhances growth hormone secretion and amplifies the complex rhythms of growth hormone secretion in man. J Clin Invest. 1988 Apr;81(4):968-75. doi: 10.1172/JCI113450. PubMed PMID: 3127426; PubMed Central PMCID: PMC329619.

9Catterson JH, Khericha M, Dyson MC, Vincent AJ, Callard R, Haveron SM, Rajasingam A, Ahmad M, Partridge L. Short-Term, Intermittent Fasting Induces Long-Lasting Gut Health and TOR-Independent Lifespan Extension. Curr Biol. 2018 Jun 4;28(11):1714-1724.e4. doi: 10.1016/j.cub.2018.04.015. Epub 2018 May 17. PubMed PMID: 29779873; PubMed Central PMCID: PMC5988561.

10Aly SM. Role of intermittent fasting on improving health and reducing diseases. Int J Health Sci (Qassim). 2014 Jul;8(3):V-VI. doi: 10.12816/0023985. PubMed PMID: 25505868; PubMed Central PMCID: PMC4257368.

Mag. Stephan Lederer, MSc.

Mag. Stephan Lederer, MSc. is an author and blogger from Austria who writes in-depth content about health and nutrition. His book series on Interval Fasting landed #1 on the bestseller list in the German Amazon marketplace in 15 categories.

Stephan is a true man of science, having earned multiple diplomas and master's degrees in various fields. He has made it his mission to bridge the gap between conventional wisdom and scientific knowledge. He precisely reviews the content and sources of this blog for currency and accuracy.

Click on the links above to visit his author and about me pages.

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