OMAD Diet vs Intermittent Fasting (16/8): Does One Meal A Day Work?

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minute read | Last update: Jan 19th2024

This article is backed by studies and reviewed by a certified dietician.

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Have you been intermittently fasting but don't see a change? Well, you've probably been advised to try the OMAD diet instead. The restrictive diet is said to yield much better results - weight loss-wise - but can it?

Science dictates that eating a single meal a day can and might work—but that doesn't mean it's healthy. Briefly put, eating one meal a day does help you lose weight but affects your health, and the effects don't last very long. It's definitely not a long-term solution.

But is the intermittent fasting pattern better? What's the difference between the two fad diets? And can either help you? Find out below.

Does One Meal A Day Work?

The OMAD or one meal a day diet works on the principle of calorie deficits. It's not that different from any other diets or concepts in that regard. It's good old-fashioned manipulation to trick your body into using stored sugars and fats as fuel.

Instead of the usual carbs, your body is forced to look for other methods of fueling the body. While it is often described as eating at oneself, it's not true. The body does not turn on itself but instead uses existing stores of fuel.

But, the lack of fat stores and sugar in the body gradually lead to weight loss. A study done in 2007 showed a slight change in body composition when there was only one meal a day and a reduced number of calories.

What is OMAD?

OMAD is a more intense form of intermittent fasting. As mentioned earlier, it requires a person to eat a single meal a day. So, there is a one-hour period where you can eat whatever you need to. The other 23-hours are filled with beverages like water, coffee, and tea.

The extreme form of OMAD is meant to push your body to lose weight faster and improve overall health. But, according to most experts, it ends up doing the opposite.


Despite the multiple studies claiming that the one meal a day diet is too harmful to undertake, there are numerous benefits. As long as the diet is not long term, then you will reap benefits such as:

  • Weight loss
  • Reduced risk of heart disease
  • Decreased blood sugar
  • Might improve metabolism
  • It might make you more alert


With the multiple benefits also come several consequences. No human can survive on a single meal a day - no matter how nutritious and calorie-filled.

  • Difficult to sustain
  • It can make you hungrier
  • It isn't any more effective than calorie restriction
  • Several safety concerns including, blood sugar and cholesterol concerns
  • Can cause issues socially

What Can You Eat?

Thanks to the convenient one-hour window the OMAD diet allows you, there are no food restrictions. You won't find any blog telling you that eating pizza is not permitted. As long as you're consistent with the timing, you can technically eat anything you want.

However, it is important to eat a nutritious meal. While it might be tempting to eat absolutely anything and everything, doing so will rid your body of essential nutrients required for daily functioning.

Instead, it's best to consume all 1200 calories required for an adult through nutritious and well-balanced meals. The meal itself needs to be consumed after the most active part of your day to improve functioning.

When it comes to beverages, it gets a little stricter. Apart from water, coffee, and tea - there are no beverages allowed. There is definitely no alcohol or sodas permitted.

Despite not being the strictest diet, OMAD can be exhausting and frustrating after a point. It's up to you and your willpower to maintain yourself.

What is Intermittent Fasting?

Unlike OMAD, intermittent fasting offers more leniency and flexibility with meals and their consumption. Intermittent fasting requires a 16-hour fasting period and an 8-hour eating window. However, you can switch up these figures and when required.

The diet does not need to be followed every day. Whether it is followed every day or twice a week depends on personal preference and requirement. But, the results are quick and visible with this dieting format.

Unlike OMAD, intermittent fasting calls for restricted calorie intake and, therefore, food. While there aren't specific meals you can make, it is crucial and necessary to be healthy and complement it with an active lifestyle. If it is to work, then there needs to be more effort than just dieting.


While weight loss is an important benefit of the diet, there's more to life and intermittent fasting than losing weight. Here are the other benefits to the diet:

  • It lowers blood sugar by 3-6%
  • Improved insulin sensitivity by 31%
  • Enhances longevity


No diet is perfect and intermittent fasting has its issues. For starters, people might overcompensate for the fasting period by eating excessive amounts during the eight-hour window.

Excessive eating can lead to weight gain, digestive problems, and more. It certainly isn't going to improve your eating habits either.

Apart from eating habits, it can cause fatigue, dizziness, and weakness. While these negative symptoms fade away after settling into a routine, it can be a difficult adjustment period.

Does It Work?

Intermittent fasting, like any other diet, isn't helpful for everybody. But, if it does suit you, it can be an incredible weight loss tool. A study conducted in 2014 showed that a person could reduce anywhere between 3-8% of their body weight over a 3 to 24 week period!

But, the diet in its most popular 16:8 format isn't suitable for everybody. These timings are the easiest to maintain as the fasting can occur during working hours such as 9 to 5. But, if you're too young or old - even these aren't recommended.

OMAD vs Intermittent Fasting (16/8)

Despite being variations of the same diet, it's important to understand the differences to pick what works for you. At the very least, it offers a more thorough understanding of different options to help you achieve your weight loss goals.


There are two main similarities when it comes to OMAD and Intermittent fasting.

Time-Restricted Feeding

Both OMAD and intermittent fasting work on the principle of time-restricted feeding. According to this principle, restricting the hours a person can eat reduces the overall calories taken in.

Instead of eating throughout the day, a person eats only during one window to stimulate the calorie deficit.

Calorie Deficit

The calorie deficit is the science behind the success of both diets. By reducing or restricting the number of calories taken in, the body is forced to use fat or sugar stored in the body to fuel it. IT reduced the fat around the belly and other parts by putting it to use!


There is also only one main difference between the OMAD and intermittent fasting diets. It boils down to OMAD being a hardcore version of the intermittent fasting diet. Instead of fasting for 16-hours as is done during intermittent fasting, OMAD requires a full 23-hour fasting window.

Is OMAD Better Than Intermittent Fasting?

The final question and the most important one in the article - is OMAD better for you?

Most nutritionists would say no, the OMAD diet does more harm than good. Eating one meal a day is not a feasible means of dieting and is not sustainable long-term. While, in theory, it follows off the success of the intermittent fasting method, OMAD takes it a step too far.

Eating only one meal a day can lead to several health complications, including blood pressure and cholesterol issues. If you're elderly or younger, it's strictly prohibited.

So, to answer the question - no, OMAD is not better than intermittent fasting. The same results can be achieved by restricting calories rather than entire meals and spreading out the calories consumed. Eating for a shorter period does not automatically make the diet more effective.

On the flip side, such time restrictive diets can increase hunger and consequently weight gain! It's also not a good choice for beginners. Going from a regular three meals to a single one might not have the intended effect on your metabolism.

Whatever diet you choose to follow, consult a doctor to avoid any unnecessary complications.

Wrapping Up

With new fad diets popping up everywhere, it is difficult to pick the one that could work for you. When there are multiple variations of the same diet, things can get even more confusing.

The intermittent fasting diet (16:8) has risen in popularity because of its efficacy and ease. It's flexible and straightforward, unlike diets such as keto. But, it also brings about long-lasting results.

OMAD is more restrictive, harder to achieve, and entirely not worth the hardship. If you choose to follow the diet, it is best to consult a medical professional before you do so.

So, what diet are you going to follow?


Can you have any calories while intermittent fasting?

Intermittent fasting doesn't restrict food choices as much as other diets. It is perfectly acceptable to consume the regular 1200 calories per day. However, it does call for a calorie deficit which will require calorie restriction.

How much weight do you lose on OMAD?

While there haven't been any extensive studies, small scale ones have shown that eating one meal a day compared to three leads to almost 4.1% loss in weight.

How to start OMAD fasting?

As a life tip, don't jump directly into OMAD or any other time restrictive diet. It's best to start with intermittent and slowly slip into OMAD. Here are some ways to get started restricting your meals to one a day. 

  • Choose a time frame in the day to consume your meal. It can be in the morning or evening.
  • Always use a dinner plate up to 11 inches in diameter to consume your meals.
  • Don't let the food on the plate be higher than 3 inches.
  • Go for nutritious, balanced meals that will keep you filled up
  • Try and stick to 1200 or fewer calories in one meal for best results.

What is the best time to eat one meal a day?

Ideally, you should consume one meal right after the most active part of your day. It could be in the morning after your routine or in the evening after a tiring day of work. It helps keep you energetic and less weak. The choice of time, however, depends entirely on your personal preference.

About the author

The Authentic Keto Team is here to bring you health tips that help you with losing weight fast. We focus on a clean keto diet for beginners because we believe that is the easiest and most simple way to healthy eating. Our keto weight loss tips will not only bring you into ketosis fast but will also help you to improve your mental health, sleep problems, and wellness.

- Our goal is to make keto success easy. -

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