The OMAD Diet: Can Eating One Meal Per Day Be Healthy?

Omad diet

OMAD Diet and effects of eating one meal a day on your body

The OMAD diet plan is not for everyone. It is a type of fasting and may have negative implications on your physical and mental health. It is not so easy to stay without food for so long time and especially if you have some health issues.

Fasting is a good thing and helps to clean your body from toxins, damaged cells, and yes it also helps to lose weight. But are you prepared for this type of fasting?

Let’s see what the OMAD diet is and how this type of fasting affects your health. What are the benefits and side effects of adopting the OMAD diet plan?

What is the OMAD Diet?

OMAD or One Meal A Day Diet is an intermittent fasting style where you don’t eat for 23 hours. At intermittent fasting, the not-eating period is for 16-48 hours. Here the ratio is 23:1. Meaning you don’t eat anything for 23 hours and you have a 1-hour open window to eat whatever you want.

Or if we simplify this means eating just once a day.

Most people do the OMAD diet starting to fast at night, skipping breakfast, and usually eat in the middle of the day, leaving 6-7 hours until they go to bed.

If you’re interested in losing weight by fasting and eating just one meal a day, here is a similar eating pattern to the OMAD Diet and is called the Warrior Diet. Here is an article for you to find out more about this eating pattern – The Warrior Diet – 20/4 Fasting | What To Know and Is It Right For You?

How To Practice The OMAD Diet 

If you want to practice the OMAD diet it doesn’t mean that you can eat whatever you want. It is recommended to stick to low-carb intake on OMAD days, and also on no-OMAD days.

It is not recommended to use OMAD daily for the reasons that are mentioned down in this article. Using OMAD one to three times a week could be effective for weight loss and metabolic health.

Tips And Tricks To Adjust To The One Meal A Day Diet

First, you should be aware that before making any changes to your diet and eating routine, talk to your doctor. It is not easy to fast for 23 hours and get all the needed nutrients from one daily meal.

Make your meals balanced

Be sure that your meals are balanced and rich with macro and micronutrients.

If you’re following a ketogenic diet in addition to an OMAD schedule, make sure to be mindful of your macros, and keep your large meal under your carbohydrate limit.

Know your body

Some organisms can’t agree with this type of 23 hours fasting, and that is just fine.

Every organism is different from others. If you have a stressful period or you exercise more often, have a fast metabolism don’t force this schedule without listening to your body.

When your body is under pressure from fasting it will release extra adrenalin or cortisol. If you are feeling constantly tired, lack energy, can’t sleep through the whole night, your body is telling you that you need more energy.

If your body is screaming for food on the 22 hours of the fast, just sit down and eat. You shouldn’t terrorize yourself because the schedule is 23 hours without food.

It’s more important to maintain your composure and keep your life on track than it is to stick to a strict timeline.

Impact on your mental health

Fasting can also have an impact on your mental health, not just physical.

Be aware of this and if you notice that you are stressed more than before, try meditating, breathing techniques to calm down, or grounding techniques to be more relaxed.

Women should be extra careful

Fasting too much can cause the brain to suppress reproductive hormones.

It also can mess with women’s insulin response. If you notice changes in your feelings or cycle shifts, be sure to see a doctor.

Here Is A Simple OMAD Diet Plan For One Week:

(thanks to DietDoctor)

Monday: eat two meals with 16:8 time-restricted eating, targeting 1,800 calories.

Tuesday: OMAD, around 1,200 calories (assuming a standard 1,800-calorie intake). Aim for 30% protein (105 grams), 10 grams carbs, and 104 grams fat. Some may find this volume challenge. If so, consider lengthening your eating window so that you eat a “snack” of nuts and cheese and then, an hour later, eat your full meal.

Wednesday: eat two meals with 16:8 time-restricted eating, 1,800 calories

Thursday: OMAD, similar to Tuesday

Friday: eat two meals with 16:8 time-restricted eating, 1,800 calories

Saturday: free day to eat how your social schedule dictates (just stay on your low-carb plan!)

Sunday: OMAD, similar to Tuesday

Benefits Of Following The OMAD Diet

Mark P. Mattson in the article Dietary Factors, Hormesis and Health says: “The most prominent dietary factor that affects the risk of many different chronic diseases is energy intake – excessive calorie intake increases the risk. Reducing energy intake by controlled caloric restriction or intermittent fasting increases lifespan and protects various tissues against disease.”

Long periods of fasting benefit your body by gently stressing your cells, making them more resilient. Using stress to make you stronger is a process called hormesis.

Fights Against Aging

The OMAD diet triggers autophagy. Autophagy helps your body to clean itself from damaged cells, toxins, and waste. This process is also known as fasting for health, not for weight loss.

Weight Loss

Because you eat only once a day the OMAD diet results in low-calorie intake. You can’t consume so many calories per meal as you can if you eat 3 or 4 times a day. Also, fasting has a big effect on your metabolism, it resets your tolerance to hunger and helps you burn fat longer.

Be careful: Prolonged calorie restriction can slow down your metabolism and this can result in some reverse effects of intermittent 23 hours fasting. So if you are struggling to eat enough, don’t do OMAD every day.

More Time for Yourself

Because you are eating just one meal per day, imagine how much time you can save on cooking, picking groceries, thinking about what healthy food to eat. You only have to plan for one meal and don’t worry about calorie intake.

Side Effects Of OMAD Diet

There are some side effects of practicing this type of intermittent fasting:

Missing out important nutrients

In that one-hour window for food, you need to pack all necessary antioxidants, minerals, and phytonutrients that are packed in fruits and veggies.

Small window to eat so large quantity of nuts, seeds, legumes, lean proteins. Normally you should intake this quantity of food in your 4 or 5 daily meals, so it is so hard to do that in an hour’s window.

Bad cholesterol levels could go up

Fasting can induce an increase in LDL cholesterol which is so opposite of what you want to do. So if you eat one meal a day and it is a highly processed fried food or too many simple carbs you will feel pretty bad even if you are losing weight.

Also the more you practice this diet your metabolism becomes slower and slower, which may lead to unwanted side effects such as weight gain.

Other risks may include

  • Shakiness and physical weakness
  • Low energy or fatigue
  • Brain fog
  • Trouble focusing

Also, it is hard to exercise regularly because you won’t be field properly. Just imagine how many meals you should miss with your partner, friends, and family.

Inadequate Protein Intake

Except for calorie restriction this type of intermittent fasting can lead to protein restriction. Proteins are very important, they help you to feel full and satisfied, and it is not possible to intake the entire daily need from just one meal.

The average male from 81-kg should eat 110 g of protein daily. If you can eat a couple of fried eggs plus 16-oz of ribeye on one serving, you shouldn’t have a problem.

But put there vegetables, fruits, nuts…And all that in one hour a day. If you can eat all of this then you shouldn’t have protein intake problems. But yes, it is too much for one meal.

Too Many Carbs

It is recommended to restrict your carb intake to less than 20 grams per day if you want to stay in ketosis. But dietitians also recommend spreading out your carb intake so your meal has no more than 10 grams.

With the Omad diet, you should theoretically eat 20 grams per one meal. And this is not good for those who are highly insulin resistant. This can result in glucose and insulin spikes.

Eating one meal a day effects on the body

Final thoughts about eating one meal a day:

This type of fasting is a big challenge for you from a physical and mental point of view. OMAD diet can surely help you to lose weight but you must have in mind the negative effects of the diet.

It is not easy to stay without food for 23 hours and eat just one meal per day. It is recommended if you want to try it consult with your doctor first.

If you’ve never fast before try it first once a week and don’t go immediately on a 23:1 ratio of fast and eat. Try first with 14:10.

Here is good reading for you if you are interested in fasting and the benefits of fasting: Benefits Of Fasting For 24 Hours And Tips For A Successful Fast.

Be sure to eat nutrient-rich foods like fruits, veggies, whole grains, and lean proteins. Don’t do the OMAD diet plan if you are pregnant, lactating, or taking medications.

It is up to you but we recommend choosing something different like early dinner and not eating anything until morning. Again consult with your doctor if you are making some changes in your eating habits.

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