Top 10 OMAD Benefits: Should You Eat One Meal a Day?

This article is based on scientific studies

OMAD Fasting | How | Long | Start | Often | Benefits | FAQ | Studies

Recently, the acronym OMAD has gone viral on social media and news. Here’s anything you need to know about starting OMAD fasting and its potential benefits.

Key Takeaways:

  • OMAD boosts productivity, cognition, metabolism, insulin sensitivity, and gut health.
  • Another primary benefit is that its simplicity saves a lot of time and money.
  • Eat one meal a day if you feel good with it – 5 days a week is enough in my experience.

What Is OMAD?

The OMAD Diet is not a diet but rather a particular intermittent fasting method. But what does OMAD mean?

OMAD is an acronym that stands for:

  • One
  • Meal
  • A
  • Day

Hence, it means that you only eat one meal a day and fast for the rest of the day. Accordingly, it is an intermittent fasting protocol, often called the 23/1 fasting method or 23/1 diet.

How to Do OMAD Fasting?

With this in mind, OMAD involves fasting for about 23 hours and eating for about one hour. However, it is not the exact time frame that is important, only that it is a single meal throughout the day.

Moreover, most people choose to eat the same meal every day. In most cases, this is the dinner.

For example, during OMAD Diet, you have dinner on Monday evening and then fast until the next dinner on Tuesday.

Nevertheless, you may just as well choose lunch or breakfast as your one meal per day. It’s up to you and your habits.

I prefer dinner. You will experience the main reasons for this preference later on and the benefits of the OMAD diet.

How Long Should I Do OMAD?

How long you stick to the OMAD interval is entirely up to you, as it is an intermittent fasting schedule, not a fad diet.

For example, you can do 23/1 OMAD on one day and 16/8 intermittent fasting the next day. Then the next meal after dinner on Monday is lunch on Tuesday.

OMAD, like other intermittent fasting methods, can be situation-oriented while offering health benefits. So you can do an OMAD day occasionally if it suits your tasks, or you can do OMAD fasting the whole week.

How to Start the OMAD Diet

Starting OMAD is an excellent idea if you:

  • are in good health
  • want to lose more than 10 pounds
  • have a tight working day schedule
  • want to prevent diseases
  • want to increase your life expectancy
  • have reached your health goals and want to maintain them with little effort

If you have not yet given much thought to your health goals or have never fasted, OMAD fasting is perhaps not the best start.

Then it’s wiser to start skipping breakfast since that’s the most natural and convenient step to implement intermittent fasting.

After a single week, you will have unlearned the trained morning appetite and can decide if intermittent fasting fits into your life.

If the following is correct, you should never start without professional guidance or consultation with OMAD:

  • You do not feel 100% healthy.
  • You have or suspect a disease, such as in particular:
    • Metabolic syndrome
    • Diabetes
    • Polycystic ovarian syndrome (PCOS)

How Often Should I OMAD?

Making one daily meal a permanent habit to maximize health benefits is possible if you feel good about it.

Moreover, you will undoubtedly feel a sharp drop in appetite during the first month of OMAD fasting.

Therefore, skipping lunch after breakfast is not too tricky because your body gets used to this eating pattern over time.

But this can also be the disadvantage of an OMAD diet.

Why Am I Gaining Weight on OMAD?

The secret to success in fasting is to trick the body. Unpredictability helps you lose weight through intermittent fasting. If you do the same thing every day, the body will adapt.

The biological principle of homeostasis characterizes the human body. Therefore, the body continually adapts to the circumstances and stabilizes body temperature, fluid, and weight.

With this in mind, the ultimate biological goal is the species’ survival.

And the body’s adaption can be a downside of making OMAD permanent. With time, the body knows how much food to expect and will adapt to the rhythm of the energy supply.

If you practice OMAD permanently, it can share some disadvantages with conventional calorie restrictions.

For example, the body will not spend as much effort to burn fat if it expects to eat at precisely the same time every day.

But fasting does not always have to be monotonous and boring. Thus, in my experience, OMAD is an excellent fasting tool you can use cleverly in everyday life.

What Are the Benefits of OMAD?

OMAD saves you time and money while boosting productivity, metabolism, and autophagy. Feel free to share the incredible benefits of OMAD using my infographic:

OMAD diet benefits infographic

1. Saves Time

There is no question why OMAD is such a popular intermittent fasting strategy today. It simplifies your life.

Accordingly, the most significant benefit of the OMAD diet lies in improved time efficiency of everyday life:

  • You don’t have to rush breakfast in the morning
  • Due to saved time, you can read the newspaper in peace or meditate as a morning routine
  • You get through your lunch hour without distractions
  • You don’t have to compromise on lunch and cheat on your diet
  • There’s no food coma in the early afternoon
  • If you are self-employed or in a home office, you can end work at 3 PM
  • Nevertheless, you can celebrate dinner with the family
  • You need to cook once a day at most

In short, OMAD sets new standards for the simplicity of intermittent fasting. New worlds will open up when you no longer plan your day around meals.

When it comes to dietary rules, simpler is better. And OMAD is probably the most straightforward fasting strategy around.

Regain control over your eating habits! And not the other way around.

2. Saves Money

If you start with OMAD, you will notice one of its most significant benefits: dramatically reducing your weekly grocery bills!

Do the following phrases of conventional wisdom sound familiar to you?

  • You must eat at least six times a day
  • Eat several small meals to lose weight
  • Snacks are healthy and help you lose weight
  • Never skip breakfast

If several meals a day promote something, then it is the revenue of the food industry. Do you love to portion and pre-cook several times a day?

Sooner or later, people will turn to processed food alternatives due to a lack of time. Therefore, one meal a day makes everything more comfortable and much cheaper.

Accordingly, you will soon realize that one natural meal a day does not cost much because the actual cost drivers are snacks and other ready-to-eat food.

In contrast to most diets, OMAD also has the advantage of not eating expensive food all day.

Organic and grass-fed products are desirable but not affordable for everybody.

OMAD saves money when buying food

3. Boosts Productivity

You’re in a focused workflow, but lunch break is right ahead. Problem solved!

What I love about OMAD Diet is the urge to get things done. One of the reasons for this is that with the fasting period, adrenaline production increases. So we don’t get tired.

Nature has foreseen mechanisms for food scarcity. Would we be here today if our ancestors immediately fatigued due to unsuccessful hunting? Probably not.

Because it is much more nature’s interest that we can search for food to survive, the body increases the secretion of specific hormones, boosting metabolism (Drenick et al. 19641).

Accordingly, I practice OMAD when I want to get things done. On the other hand, I don’t find the OMAD fasting ideal when I need to think more deeply or be creative.

Due to the sharpened survival instinct when fasting over lunch, you will focus on the essential things and make decisions faster.

Therefore, One Meal A Day is ideal for repetitive work. Also, it fits if you do analytical tasks in the morning and repetitive tasks in the afternoon.

For example, thanks to the time gained, you can finish work earlier and use your adrenaline boost for sports.

4. Promotes Autophagy

Fasting induces autophagy, a natural cleansing mechanism that replaces broken cell components with new ones and drains toxins from the body.

Accordingly, autophagy is one of the most significant health benefits of fasting.

Since the fasting detox promotes the prevention of cancer, diabetes, liver, or autoimmune diseases, the discovery of autophagy was awarded the Nobel Prize for Medicine in 2016 (Levine et al. 20172).

Moreover, it slows down the aging process.

Although there is no scientific consensus, most theories assume that autophagy does not start until you fast for more than 16 hours.

For this reason, OMAD Diet is a better tool for longevity than regular 16/8 intermittent fasting.

5. Increases Basal Metabolic Rate

Scientists have proven that prolonged periods of fasting increase the basal metabolic rate a long time ago (Drenick et al. 19643).

Hence, that fasting slows down metabolism is a myth.

As mentioned, the body elevates hormones such as adrenaline and the human growth hormone (HGH) during periods of fasting (Ho et al. 19884).

Therefore, your body accelerates metabolism to search for food for longer. And this increases the ability to burn fat for energy.

Therefore, a person can go without food for a few days. But don’t be afraid of the OMAD diet because the world record for fasting is an unbelievable 382 days (Stewart et al. 19735).

6. Boosts Insulin Sensitivity

Due to the flawed definition of “healthy” and the resulting Western diet, insulin resistance assumes almost pandemic proportions.

Since especially refined carbohydrates and sugars stimulate the production of the storage hormone insulin, astronomically high insulin levels result.

The body protects itself against this hormonal threat by reducing the insulin sensitivity of the cells.

However, insulin resistance means the body needs to secrete even more insulin to trigger vital functions. As a result, the risk of chronic diseases dramatically rises, such as:

Records of fasting as an effective treatment for insulin resistance date back to 1969, but its effects have been known for over 100 years (Jackson et al. 196911).

Furthermore, recent studies show intermittent fasting can be a safe treatment for insulin resistance (Catenacci et al. 201612).

Research shows that regular OMAD fasting benefits your insulin sensitivity and does not just reduce insulin levels.

Science shows that Intermittent fasting can reverse insulin resistance and even type 2 diabetes, which diets alone usually can’t (Halberg et al. 200513).

7. Helps Build Muscle

Contrary to what most people believe, fasting does not atrophy the muscles.

An important reason why our body goes into ketosis is to preserve muscle mass.

Many of our metabolic pathways focus on conserving muscle at all costs. The misconception that fasting reduces muscle mass arises because if we fast for long enough, protein is broken down and converted into glucose.

However, this is not muscle protein. In contrast, the body focuses on blemished skin and intestinal mucosa proteins, which it needs to replace anyway.

Do you remember the effects of autophagy we just discussed?

Hence, to protect lean mass, your body releases counter-regulatory hormones.

One of these is the human growth hormone or somatropin. During fasting, the growth hormone release reaches peak levels to ensure you do not lose muscle.

Therefore, OMAD protects lean and bone mass (Rudman et al. 199014).

Accordingly, fasting is one of the most effective natural growth hormone stimulators (Ho et al. 198815).

In short, fasting is anabolic biohacking.

Therefore, fasting, exercise, and meat or fish are effective combinations for building muscle.

They provide your body with everything it needs to build muscle mass:

During your 23 hours OMAD fasting period, growth hormone is elevated, and the body benefits from synthesizing muscle proteins more efficiently.

Similar to autophagy, this renewal process makes muscles more robust than before.

8. Improves Cognition

Fasting is a signal to the body that no food is available. Contrary to conventional belief, your body does not shut down.

On the contrary – it turns on the turbo boost.

As a result, the body activates the sympathetic nervous system and releases adrenaline, cortisol, and growth hormone.

In short, your body pushes as much energy into the bloodstream to fuel hunting for food. Hence, cortisol, adrenaline, and growth hormone prepare us for the hunt for food.

Therefore, many people report increased cognition and focus when fasting.

Accordingly, one study found no reduced cognition and activity in subjects, although they ate almost nothing for two days (Liebermann et al. 200816).

Moreover, the main reason for the drop in productivity in the afternoon is the breaking of the fast. Because eating allows the body to relax, the sharpened focus fades.

Additionally, fasting increases the brain-derived neurotrophic factor (BDNF), improving cognitive function.

Since BDNF is a neural growth hormone, it’s responsible for forming neurons in your brain. Therefore, high BDNF levels are associated with increased intelligence, mood, and memory.

When you release BDNF, your brain can form new nerve connections. For this reason, fasting can improve the memory of older people and counteract Alzheimer’s and Parkinson’s disease (Witte et al. 200917).

OMAD Diet fosters formation of neurons

9. Boosts Fat-Burning

As diabetes specialists already knew in 1916, fasting is a natural way to burn excess sugar and fat in the body.

Recent studies claim intermittent fasting burns dangerous visceral fat more effectively than a low-carb diet (Catenacci et al. 201618).

Hence, fasting forces the body to burn stored fat for energy. And that’s why we store fat in the first place. It’s meant for times of food scarcity.

Therefore, body fat storage is a survival mechanism. Nevertheless, we have used this mechanism so rarely that we almost lost the ability to burn fat for energy.

Accordingly, OMAD Diet is a simple but effective way to maximize the time we can burn fat daily. Hence, we train our bodies to burn fat more efficiently.

Moreover, hormones like norepinephrine keep the basal metabolic rate high during this time of fasting (Zauner et al. 200019).

10. Promotes Gut Health

Intermittent fasting is one of the best ways to improve gut health since it allows your intestines to rest.

At the same time, bad gut bacteria starve. This way, fasting also reduces inflammation.

But even shorter periods of fasting are helpful. With this in mind, a recent study found an increase in life expectancy, even with short periods of intermittent fasting.

Furthermore, according to the study, intermittent fasting sustainably improves gut health (Catterson et al. 201820).

For this reason, many people start OMAD fasting precisely because of its positive effect on intolerances and inflammation.

My Experience

One Meal A Day is an intermittent fasting method, not a diet. However, this makes it much easier to use, as no strict dietary rules exist.

Since it’s a fasting method, the benefits of OMAD fasting are most effective with a high-fat diet such as the Keto diet.

Those who consume a lot of carbohydrates with one meal a day will significantly extend the time it takes to get into ketosis and burn fat for energy.

The OMAD fasting method is an effortless routine to integrate into everyday life, offering more than only health benefits. It also saves time and money, as there are no sophisticated rules to follow.

My experience with OMAD is that the flexibility and efficiency it brings are ingenious. Although One Meal A Day is a powerful tool, I do not see OMAD as a strict diet.

For example, with OMAD, you can increase your productivity during the week but eat and relax on weekends.

In this way, you also prevent your body from permanently adjusting to OMAD and thus causing a weight loss plateau.

Whether OMAD fits into your everyday life, you have to decide. Nevertheless, this form of fasting is more natural to integrate than other diets due to its simplicity.

Share with us how you could integrate OMAD into your everyday life to reap the most benefits in the comments section (at the bottom)!


intermittent fasting for beginners book

Frequently Asked Questions (FAQ)

Can I eat anything on OMAD?

Technically you can eat anything on OMAD. But since it’s a fasting method, it best works with a low-carb diet like keto. These methods aim at tapping into body fat for energy 🔥.

Can you lose weight by eating one meal a day?

Eating one meal daily is an effective method to burn fat for energy 🔥 because you fast 23 hours a day. Therefore, you can lose weight on the OMAD diet.

Can you drink coffee on OMAD diet?

You can drink ☕ coffee on the OMAD Diet, but it needs to be without milk and sugar not to break the fast.

How does OMAD help you lose weight?

OMAD is one of the most effective methods to burn fat for energy 🔥 and lose weight because you fast 23 hours a day.

Is OMAD everyday OK?

If you are healthy, you can do OMAD daily. I have been doing it for years without problems.

What do you eat on an OMAD diet?

A ketogenic diet is the best way to maximize weight loss with OMAD.

Is OMAD good for your body?

Yes, it improves cognition, gut health, basal metabolic rate, and lean mass.

What happens if I eat one meal a day and exercise?

You will have it easier to gain lean mass.

What are the long term side effects of OMAD?

The primary side effect is Stress: the longer the fasting period, the higher the alertness.

What is the best time to eat for OMAD?

In my experience, it is best to eat between 3 and 9 pm.



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2Levine 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.

3DRENICK 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.

4Ho 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.

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7Athauda D, Foltynie T. Insulin resistance and Parkinson’s disease: A new target for disease modification?. Prog Neurobiol. 2016 Oct – Nov;145-146:98-120. doi: 10.1016/j.pneurobio.2016.10.001. Epub 2016 Oct 3. Review. PubMed PMID: 27713036.

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10Kong LC, Wuillemin PH, Bastard JP, Sokolovska N, Gougis S, Fellahi S, Darakhshan F, Bonnefont-Rousselot D, Bittar R, Doré J, Zucker JD, Clément K, Rizkalla S. Insulin resistance and inflammation predict kinetic body weight changes in response to dietary weight loss and maintenance in overweight and obese subjects by using a Bayesian network approach. Am J Clin Nutr. 2013 Dec;98(6):1385-94. doi: 10.3945/ajcn.113.058099. Epub 2013 Oct 30. PubMed PMID: 24172304.

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12Catenacci 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.

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14Rudman 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.

15Ho 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.


16Lieberman HR, Caruso CM, Niro PJ, Adam GE, Kellogg MD, Nindl BC, Kramer FM. A double-blind, placebo-controlled test of 2 d of calorie deprivation: effects on cognition, activity, sleep, and interstitial glucose concentrations. Am J Clin Nutr. 2008 Sep;88(3):667-76. doi: 10.1093/ajcn/88.3.667. PubMed PMID: 18779282.

17Witte AV, Fobker M, Gellner R, Knecht S, Flöel A. Caloric restriction improves memory in elderly humans. Proc Natl Acad Sci U S A. 2009 Jan 27;106(4):1255-60. doi: 10.1073/pnas.0808587106. Epub 2009 Jan 26. PubMed PMID: 19171901; PubMed Central PMCID: PMC2633586.

18Catenacci 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.

19Zauner C, Schneeweiss B, Kranz A, Madl C, Ratheiser K, Kramer L, Roth E, Schneider B, Lenz K. Resting energy expenditure in short-term starvation is increased as a result of an increase in serum norepinephrine. Am J Clin Nutr. 2000 Jun;71(6):1511-5. doi: 10.1093/ajcn/71.6.1511. PubMed PMID: 10837292.

20Catterson 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.

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.

This Post Has 8 Comments

  1. Sigrid

    Good work on this summary. Much appreciated information.

    1. Thank you, Sigrid! Appreciations like yours are the fuel for passionate work 🙂 Have a great day, and feel free to share ideas for new topics you are interested in!

  2. Danielle

    “Those who consume a lot of carbohydrates with one meal a day will significantly reduce the time it takes to get into ketosis and burn fat for energy.” Don’t you mean the opposite of this?

    Very good article. I like that you included your sources. Thank you.

  3. Bob

    I appreciated your summary very much. I have been doing a 20-4, with an occasional OMAD, for approximately 40 days, and I have definitely experienced the benefits. Would it be possible for you to add an excerpt about Insulin production and how, while your body is producing insulin when you eat, it blocks the body from burning fat stores? This was a key component in helping me understand how/why fasting works the way it does.

  4. uyi

    if fasting raises metabolism, why do most people tend to regain the weight they lost after restricting calories? also, is the key to preventing your body from adjusting to omad to alternate between fasting and eating normally? is omad meant to be indefinite to maintain weight loss?

    1. Hi,

      #1 You are confusing fasting with conventional dieting based on calorie restriction. The first is about strict periods without food intake, the latter about numerous low-calorie meals throughout the day. While strict fasting improves metabolism, conventional dieting slows down the basal metabolic rate in the long run by high insulin and low growth hormone levels resulting in muscle loss – we know this phenomenon as yo-yo dieting.

      #2 Fasting offers a lot of flexibility, e.g., you can eat more/more often on days with intense workouts and stick to OMAD/skip meals on rest days.

      #3 How long do you want to maintain weight loss? There will be a target weight you want to hit. You can also easily switch back to 16/8 to maintain your goal weight once it’s hit.

      I hope that was helpful.


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