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Everything You Should Know About OMAD Before Starting

There are several ways to practice intermittent fasting: from accessible 12-hour fasts to challenging day-long stretches with no food intake. The OMAD method falls somewhere closer to the latter group.

The idea behind this specific regime is to consume all daily caloric needs within a single meal, which can bring various health benefits like reduced inflammation, improved heart health, and stabilized blood sugar levels.

But how exactly does the OMAD diet work? Is it safe? Can one really gain all the nutrients needed in one single meal? Stick with the article to find out.

What Is OMAD?

OMAD, or One Meal A Day, is a variation of intermittent fasting. Also referred to as the 23:1 diet, it involves a fasting period that covers most of the day, allowing only a small eating window to consume all your daily calories.

This time-restricted eating method is an effective tool for rapid weight loss, and it can be helpful for those who have plateaued in their weight loss journey.

However, it must be highlighted that the OMAD diet is an advanced intermittent fasting style. If you’re new to fasting, you may find it easier to start with other methods to get your body used to time-restricted eating.

It is also important to note that the One Meal a Day diet may not be an effective tool for long-term weight loss (we’ll see why below), so it might be best used infrequently or for a short period only.

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How Does One-Meal-a-Day Diet Work?

The OMAD diet, commonly known as the One Meal A Day diet, is based on the same principle as other intermittent fasting styles—by limiting the time range in which food is consumed, one can lower their overall calorie consumption, which brings a plethora of health benefits to the body.

This diet allows one meal every 23 hours, giving you one hour to consume all the nutrients you need for the day before going back to fasting. This is an effective fasting method that allows your body to enter ketosis, a metabolic state in which your body burns fat for energy instead of its usual energy source—glucose.

When you get all of your daily calories in a single meal, as in the OMAD diet, your body is forced to use stored fat as fuel for the rest of the day, resulting in weight loss and a boost in metabolism.

However, while following this regime, not all foods are equal—it is critical that you have a nutritious meal when your eating window opens, as consuming a well-balanced, nutrient-dense meal helps the body maintain energy levels and appropriate functioning while also avoiding malnutrition.

Remember that this method isn’t a long-term approach to weight loss, as long periods of fasting can cause the body to fall into a semi-starvation mode where muscle mass may be burned for fuel instead of fat.

Most people use the OMAD method sparingly throughout the week or as a kickstart to a weight loss journey.

How to Succeed When Following OMAD?

The OMAD method has multiple health-related benefits and can help you successfully lose weight. Here are some guidelines to do it the right way.

1. Try OMAD only when comfortable with other fasting types

If you’re a beginner faster, you might want to begin with more accessible intermittent fasting types (12:12, 14:10, 16:8, and so on) before trying the OMAD approach, as this is an advanced fasting method that can be challenging for starters. By beginning with more manageable fasting programs, you can ease your way into prolonged fasting periods, increase your tolerance for hunger, and reduce feelings of deprivation.

You can try the OMAD method when you’ve become used to shorter fasts and understand how your body reacts to intermittent fasting.

It is critical to listen to your body and make modifications as needed to ensure that you are following the diet in a sustainable and healthy manner.

2. Carefully plan which hour should be set to eating OMAD

Meal planning is essential, as the quality of the foods you choose and the time when you decide to eat them will directly affect how you feel and the activities you do on your fasting days.

The most important rule to stick to when following the OMAD diet is to eat at the same time every day. By doing this, you’re likely to feel fewer hunger pangs at inconvenient times, and you’ll be able to understand and regulate your energy levels better.

In order to choose the right time for your meal, identify when you are most hungry during the day and arrange your meal accordingly. For example, if you can’t focus on your work without breakfast, just eat first thing in the morning.

Remember that you should not eat right before bed, as doing so can interfere with your sleep cycle. Always try and have your last meal of the day around 2 hours before your sleep time.

3. Exercise only after the eating window during OMAD

Even though physical activity is an integral part of weight loss and a healthy lifestyle, there are some things you need to consider if you want to exercise while practicing the OMAD method.

During the first days following this eating pattern, it’s generally recommended to exercise a few hours after your eating window, so you can use the energy you just obtained from your meal in your workout.

Once you’ve become a more advanced faster, you can choose to work out at later times. You can even consider exercising 12 hours after your last meal, when your body will enter ketosis. Doing physical activity at this time can boost fat burning and the overall benefits of fasting.

However, it’s important to remember that every body is different. If you feel lightheaded, weak, or dizzy during a fast, hold off exercising until you have had a meal.

4. Try using fasting supplements to help with hunger pangs during OMAD

In addition to helping you adhere to your intermittent fasting routine, appetite suppressants typically offer nutrients to your body while carrying relatively few calories. With these supplements, your body gets the fiber and nutrients it normally gets from eating three meals a day without breaking your fast.

If you feel extremely hungry during your fasting windows, try an appetite suppressant like the DoFasting essential fiber box. Not only can they make it easier for you to stick to your fast, but they will also encourage natural fat loss and boost your metabolism.

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4 Health Benefits Of Doing OMAD

People try the OMAD diet because of its diversity of health benefits. Let’s dive into 4 of them.

1. Helps regulate blood sugar

Intermittent fasting programs, such as the OMAD diet, help regulate blood sugar levels, reduce the risk of developing cardiovascular disease and diabetes, and prevent hunger pangs.

Whenever we eat, our blood sugar levels naturally rise as our bodies digest the glucose in our food. The hormone insulin, produced by the pancreas, aids in regulating these levels by stimulating glucose storage in cells. In short—by eating just one meal per day on the OMAD diet, you can reduce the number of sugar spikes your body experiences throughout the day.

This lower frequency and intensity of insulin spikes can assist in managing your average sugar levels and trigger the burning of glucose and fat for energy, reducing the need for insulin. Following this diet can help stabilize your blood sugar levels, which can positively impact your overall health.

2. Reduces the inflammation in the body

Fasting has been linked to reduced inflammation in the body.

Inflammation is the body’s natural response to injury, infection, or tissue damage. However, when this response doesn’t go down on its own, it can become an issue in the long term.

Chronic inflammation can lead to various health issues and increase the risk of heart disease, type 2 diabetes, and certain types of cancer.

The OMAD diet can help the body promote the production of anti-inflammatory signaling molecules and reduce the production of pro-inflammatory signaling molecules, helping you reduce inflammation in both its acute and chronic variants.

Reduced inflammation can, in turn, help ease the symptoms of autoimmune disorders, reduce the risk of certain diseases, and improve your energy and mood.

3. Improves heart health

Fasting regularly can help you improve insulin resistance, which can prevent the development of cardiovascular diseases. This is because insulin regulates blood sugar levels, which can reduce the risk of weight gain and diabetes, both factors for heart disease.

Moreover, the OMAD diet and other fasting types can improve cholesterol levels, helping you reduce your levels of LDL cholesterol (known as “bad cholesterol”) and increase the levels of HDL cholesterol (known as “good” cholesterol).

The regulation of these two kinds of lipids can reduce the risk of cardiovascular diseases like stroke, heart failure, or coronary artery disease.

4. Accelerated weight loss

People commonly start intermittent fasting to lose weight, reduce body mass index numbers, and effectively burn fat.

By eating only one meal per day, you enforce a calorie restriction on yourself, resulting in a calorie deficit necessary for weight loss. Moreover, once you have gone through at least 12 hours without eating, your body will reach the state of ketosis, boosting your weight loss process even further.

It is also believed that fasting for brief periods can enhance metabolic health, aiding in weight reduction even after fasting.

What Are the Cons of Doing OMAD?

A strict OMAD diet, like many other weight loss approaches, has certain downsides. Many of its adverse effects will disappear as your body adjusts, but you should be aware of them before making any lifestyle changes.

You are more likely to experience malnutrition

While this approach may result in weight loss for some people, it can also increase the danger of malnutrition or a lack of critical nutrients required for optimum health.

When you just eat one meal per day, it becomes harder for your body to get all the critical nutrients it needs, such as vitamins, minerals, fiber, and other important components of a balanced diet.

Malnutrition can trigger symptoms like:

  • Weakness
  • Fatigue
  • Muscle wasting
  • Headache
  • Low mood

Undernutrition can also lead to the development of chronic diseases when it becomes a permanent issue.

If you feel any of the symptoms mentioned above, either during your fast or a few days later, consider getting a check-up to ensure you stay adequately nourished.

May lead to extreme hunger and binge eating

The OMAD diet is a highly restrictive eating pattern involving consuming only one meal every 23 hours, which can trigger intense hunger and binge eating episodes. This can be harmful to your health, since ingesting an inadequate amount of food during the eating window can result in extreme hunger and even lead to binge eating.

Sufferers of compulsive eating tend to overeat large amounts of food quickly, often choosing high-calorie snacks and meals with bad fats and added sugars. These kinds of foods, when consumed abruptly and in large quantities, can cause weight gain and various symptoms such as headaches and digestive issues.

Although using appetite suppressants may help alleviate certain hunger cravings, it’s crucial to note that the OMAD diet may not be a sustainable long-term option due to its impact on hunger. In fact, having an empty stomach during this diet can raise ghrelin levels (the hunger hormone), further fueling appetite and potentially leading to binge eating.

It’s also crucial to avoid overeating during your eating window to prevent severe health issues. If you decide to try the OMAD approach, plan your meals ahead and get rid of any foods that could keep you from sticking to your plans.

Having just One Meal a Day may trigger an eating disorder

Eating disorders are significant mental health conditions with long-term and sometimes fatal implications. Restrictive diets like the OMAD diet can intensify disordered eating patterns and contribute to an unhealthy fixation with food and weight. This can lead to binge eating, overeating, and other harmful behaviors that disrupt everyday living and well-being.

It’s important to note that diets like the OMAD diet aren’t for everyone and can be dangerous in some cases, especially for people with a history of eating disorders or who are prone to them. Before beginning any new diet, consult a healthcare expert to ensure it is safe and appropriate for you.

What Kind of Foods to Eat and Avoid During OMAD?

The eating period during the OMAD diet is your only chance to eat in a whole day, so prioritizing nutritious foods from each basic food group during this hour is essential.

To minimize the chances of suffering from this diet’s side effects and learn how to create a large meal of nourishing food, check out the lists below.

Foods to include in your One Meal a Day

You only get a meal per day—so you should make the most out of it, nutritionally speaking.

The foods you should add to your dish are whole, healthy, and nutrient-dense foods that replenish and nourish the body. These include:

  • Fruits: like berries, citrus fruits, and bananas. Fruits have lots of vitamins, minerals, and fiber, which are essential for the body to carry out its basic functions.
  • Vegetables: like kale, broccoli, cauliflower, baby carrots, and pepper.
  • Starchy vegetables and grains: including squash, oats, and barley.
  • Healthy fats: including those found in extra virgin olive oil, avocado, nuts, and seeds.
  • Legumes: peas, chickpeas, and lentils.
  • Nuts and seeds: like almonds, sunflower seeds, pumpkin seeds, and walnuts. You can eat them whole or lightly roasted.
  • Dairy or alternatives: including milk, Greek yogurt, coconut milk, oat milk, and soya milk. Remember to opt for unsweetened versions, as sweetened products may contain sugar, which won’t really help in your upcoming fast.
  • Protein: like lean meat, tofu, fish, and eggs.

The foods you consume during your eating hour are critical for ensuring optimal nutritional intake, a balanced metabolism, and avoiding some harmful side effects, such as:

  • Irritability
  • Hunger
  • Fatigue
  • Digestive discomfort

Foods to avoid during OMAD

No food is forbidden in the OMAD program, as this fasting style prioritizes when and how often you eat over what you eat.

That said, certain foods can lead to cravings and adverse side effects even on a regular diet, so it could be wise to avoid them while eating a single meal a day. Foods you shouldn’t include in your daily menu include:

  • Fast food: french fries, burgers, pizza, hot dogs, etc.
  • Highly processed foods: chips, sugary drinks, ice cream, chocolate, candy, etc.
  • Sugar-heavy baked goods: pies, donuts, buns.

Foods heavy in added sugars, bad fats, and artificial additives but poor in vitamins and minerals are called empty calories. These meals supply a lot of calories but relatively few nutrients, which means they don’t help your body meet its nutritional needs. Instead, they can lead to weight gain, an increased risk of chronic illnesses, digestive pain, and dietary deficiencies.

While following the OMAD program, it’s essential to avoid foods low in nutritional value, as they do not contribute to fulfilling your body’s nutritional requirements, can make you feel weaker during your fast, and hinder any progress you may have previously made.

OMAD Meal Example

If you want to give OMAD a try but can’t think of what to do to get a nourishing meal, look at this example: it’s packed with healthy nutrients, gathers ingredients from all basic food groups, and brings a decent number of healthy calories to keep you going during your fasting hours.

Oven-baked Camembert with salmon salad:

  • Oven-bake one piece of camembert (250g).
  • Cook a cup of quinoa seeds. Serve with camembert on top.
  • Prepare the salad:
  • Take 300 grams of raw pink salmon. Steam it to the desired level.
  • Let it cool a little. Wash 100 grams of baby spinach leaves and mix it with 100 grams of dried pumpkin seeds and 100 grams of sunflower seeds.
  • Add salt as desired. Put one teaspoon of extra virgin olive oil.
  • Put one sliced avocado and the prepared salmon on top.
  • Optionally, slice one red onion and add it to the bowl.
  • Put one cup of cherry tomatoes (you might grill them if desired) and spray some balsamic vinegar.
  • Take two medium-boiled eggs, slice them, and put them on the side of the salad bowl.

Eat together with one slice of wholemeal rye German bread.

The meal has 1400 calories, is low-carb, and contains 100% of all your daily recommended vitamins and minerals.

Should You Start Fasting Now?

The OMAD diet, or the One Meal a Day diet, is a strict diet in which you consume just one meal each day and fast for the remaining 23 hours. While some individuals have reportedly lost weight and enjoyed its health benefits, it is important to note that this regime is unsuitable for beginners and may carry some considerable health risks.

Whether or not to start the OMAD diet should be based on your current health, nutritional needs, lifestyle, and personal preferences. It is a great way to lose weight and enhance your health, but you should start with simpler routines if you have never fasted before.

Moreover, if you’re taking any medications or are suffering from any health condition, you must consult your doctor before starting this or any diet—they can help you understand whether this is the right decision for you and offer alternatives if necessary.

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The OMAD diet might be challenging for some people and isn’t a sustainable weight loss option. Still, it does bring important health benefits that make it worth a try—especially if you are an experienced faster looking for a way to up your intermittent fasting game.

Eating one meal a day can improve your sugar levels, boost your heart health, reduce inflammation, and help you lose weight. However, you should consult a medical doctor before kickstarting your weight loss journey to ensure that the diet is the best option for you.


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This is an evidence-based article that includes scientific citations. DoFasting’s professional writers and editors prepared the content, which a team of medical experts verified to be accurate.

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