is a 5 day on 2 day off fast regimen healthy/safe?

I have decided to start IF again as it seems to be the best idea for my busy lifestyle. I plan on doing 20 -24 hour fasts each day( finish eating by 9pm and then don't eat again until 5pm the following day for a 24 hour, or not eating again until 1pm the next day for a 20hr), and then on the weekends only doing maybe 16 hour fasts.

I know you can do daily fasting of about 16hrs, but I can't find any evidence of doing it longer on a daily basis causing bad health issues.

I was wondering if anyone would have any advice in regards to this.

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