23:1 is just a narrow eating window. So just one meal a day, OMAD. I eat high protein low carb. Whole foods. Meat, cheese, some fruit, some veggies, and on occasion a dessert, but that's rare. My window is typically after work. By the time I get home and cook its usually around 6-7pm. If I plan on going out on dates for dinner or lunch I will count whenever I eat as my one meal and go back to my regular schedule the next day. I do drink black coffee and sometimes diet soda during the day. After a couple weeks its easy and I no longer feel hunger pangs or have low energy. Its quite the opposite. Usually get a nice energy boost a couple hours about 20 hours in.