OMAD is a type of fasting that allows you to have one meal a day, unlike intermittent fasting, where the 8-hour window is often enough for two meals. It is a diet that is not sustainable and should not be practised permanently. However, it can help you maintain (or lose) weight in stressful times when your willpower is needed elsewhere.
OMAD is for folks who are always hungry in the evening
I have noticed one fascinating aspect of my eating behaviour that predisposes me to OMAD: I'm always hungry in the evening, no matter how I eat earlier in the day.
I haven't eaten breakfast since college and have never missed it. However, I have always enjoyed full, hot meals for lunch. Well, and in the evening, that was always the time when I looked at the calorie target and had to ask myself: how much is left? And you know how it is: in the evening, the willpower is usually exhausted, then the calorie target is ignored and weight gained. First, there are single exception days, then a few days in a row, and it becomes a permanent condition at some point.
At some point, I realized that it didn't matter whether I ate lunch or not: I was still hungry in the evening.
OMAD is a willpower hack
Similar to the morning routine, OMAD is also a tool to bypass periods of stressful days, as willpower, like a muscle, becomes more and more exhausted throughout the day, bit by bit, until there is nothing left.
While I still find it easy to moderate my appetite at breakfast and lunch, I tend to binge in the evening.
The sustainable solution, of course, is to manage willpower throughout the day better and recognize the limits so that I still have enough left in the evening. But sometimes, it just doesn't work, and then I reach for OMAD.
OMAD has many advantages, but also one serious disadvantage
OMAD makes it very easy to maintain a calorie deficit. In my case, it's about eating no more than 3100kcal at 2100kcal resting + 2000kcal activity energy to achieve a 1000kcal calorie deficit equivalent to 1kg weight loss per week.
And since when I eat 3000kcal, I feel complete, staying at that limit is no problem; it can sometimes be even hard to eat so much in one session. When appetite comes during the day, resisting is usually no problem since it's only until the evening. When I practice OMAD, I quickly lose 1kg of body weight every week.
A nice side effect is that you can exercise on an empty stomach in the morning, which can be suitable for training the metabolism to rely on fat.
The caveat is inadequate sleep.
There are several disadvantages of OMAD. I would include, for example, that you are more inclined to eat unhealthy food because you don't have to watch the calories in the evening. Of course, it is not only about the number of calories but also the food quality.
It is also difficult to reconcile this with social life. A waiter in a restaurant in my neighbourhood still has to grin when he sees me because I once ate three portions at his place in the evening, and he didn't believe it at first. With my girlfriend, it's no problem, but at business dinners, it can seem weird.
The core catch, however, is poorer sleep. With an Apple Watch, you can track that well: The heavier you eat in the evening, the higher your resting heart rate at night and the less peaceful your sleep. This deprives you of precious energy that cannot be gained in this way during sleep. In addition, I used to get stomach aches during the day when I drank too much coffee on an empty stomach.
Therefore, I would recommend not running OMAD for more than two months at a time. Tendentially even less.
I hope this article helps you better assess if you have a use case for OMAD and what you need to consider. Feel free to subscribe to this blog to hear more tips on living a productivity-driven life.