The OMAD diet (also called the one meal a day diet) is a form of intermittent fasting that involves eating one meal a day.
A lot of people follow the OMAD diet for weight loss and overall health. Some people find that eating one meal a day makes calorie restriction easier, and OMAD offers all the benefits of intermittent fasting.
Here’s a closer look at the OMAD diet, benefits of OMAD, risks and concerns about OMAD, and a 7-day OMAD meal plan.
The one meal a day (OMAD) diet is a type of intermittent fasting diet. It focuses on meal timing instead of cutting calories or restricting food.
On OMAD, there’s only one rule: you eat all your daily food in a single meal.
Typically, people set a one-hour eating window for themselves each day.
You can set the window whenever you’d like. If you prefer eating breakfast, your window could be between 9-10 AM. If you prefer dinner, it could be 6-7 PM.
Similarly, you can eat anything you want on OMAD. Keto, low-carb, high-carb, vegan — whatever works for you, as long as you eat all your daily calories within a one-hour window.
There are several potential health benefits of the OMAD diet.
A lot of people use OMAD to lose weight because it makes calorie restriction easier.
If you fast all day and only eat one meal — even if it’s a large meal — you’re likely going to come in under calories for the day.
You can also satisfy your food cravings and go to bed full, which may make long-term fat loss more sustainable.
Lower Blood Pressure
High blood pressure is the single largest risk factor for cardiovascular disease[*]. It’s particularly tied to heart attack and stroke, and also puts people at increased risk of developing type 2 diabetes[*].
Longevity and Anti-Aging
Not surprisingly, studies show that fasting and caloric restriction increase lifespan in both animals and humans, and that fasting supports healthy aging[*]. OMAD is a convenient way to take advantage of these benefits.
OMAD has several health benefits, but it also comes with risks.
May Promote an Unhealthy Relationship with Food
Fasting all day and focusing on one large meal could lead to binge eating or control issues around food.
If you tend toward binge eating or struggle with anorexia, bulimia, or another eating disorder, OMAD may not be for you. Consider working with a nutritionist or registered dietitian to find an eating pattern that better suits your goals.
Mixed Results on Blood Sugar
A 2007 study found that OMAD decreases glucose tolerance and blood sugar stability in participants[*].
However, other studies have found that intermittent fasting improves glycemic control and stabilizes blood sugar[*].
OMAD may affect different people differently. If you try OMAD and develop symptoms of low blood sugar — nausea, vomiting, dizziness, blurred vision, or slurring speech — eat something immediately. OMAD may not be for you.
If you’re going to try OMAD, it’s important to do it safely.
Because you’re only eating once a day, you want to make sure you’re meeting all your nutritional needs. There are a few things to keep in mind when doing OMAD.
Eat Enough Calories
The U.S. Food and Drug Administration (FDA) recommends a minimum of 1200 calories a day if you’re sedentary, and more if you’re working out or have a physical job[*].
To make OMAD sustainable, be sure that your daily meal is at least 1200 calories. Eating less than that long-term could lead to nutritional deficiencies.
You also want to be sure you’re getting enough protein. The FDA suggests 50 grams of protein a day, but in reality, your body will do better with more than that[*].
A good rule-of-thumb is to eat at least 0.5g of protein per pound of body weight (for example, a 150-pound person would eat 75g or more of protein per day).
It can be challenging to get that much protein in a single meal. Prioritize high protein foods like steak, chicken, or fish, or use a protein powder.
Choose Nutrient-Dense Foods
You don’t have to eat perfectly on the OMAD diet, but try to prioritize nutrient-dense foods like meat, fish, dairy, eggs, nuts, and veggies.
Choosing nutrient-dense foods ensures that you meet your micronutrient needs, which can be challenging when you’re only eating one meal a day.
This 7-day OMAD meal plan includes high-protein, nutrient-dense meals that will keep you healthy.
The OMAD diet is a more extreme version of many other intermittent fasting weight loss plans. OMAD can be useful for weight loss and may improve overall health.
While OMAD works well for a lot of people, it’s not for everyone. If you struggle with disordered eating or OMAD is causing you side effects, consider trying a less intense intermittent fasting diet. You may also want to try a diet that focuses on food quality, like the ketogenic diet.