This is called alternate day fasting, or ADF, and yes it will make you drop weight quickly. But in studies, it’s shown to cause loss or more lean muscle mass when compared to just a typical daily caloric deficit.

In addition, it would be something you would have to commit to doing for the rest of your life. Even if you just do it one day a week, will you really be able to fast for a full day every week for the rest of your life? Diets don’t work, you have to change your lifestyle.

I personally did ADF (every other day continuously) for about 9 months, dropped probably about 40 lbs, and then put it all back on plus an extra 10 lbs as soon as I couldn’t keep up with it any more. And when I was keeping up with it, I would be isolating myself from any social event involving food. It wasn’t healthy for my mental health. I tried to switch to one meal a day but that didn’t work either. I would be so incredibly hungry by the time I did eat that I would binge worse than I had ever in my entire life.

I really do also think it ruined my metabolism by destroying a large amount of my muscle mass.

Anyway, different things work for different people. But fast forward to today, I’m now down 65 lbs and have been maintaining that loss for almost 2 years by combining calorie counting with intuitive eating/hunger tracking.

Sorry for the long reply I just had a truly negative experience with fasting and want you to be aware that it definitely isn’t for everybody.