Amount I’d lose if I fast 1 week, 2 weeks or 1 month

Answer

For extended fasts – two weeks or longer – I find the average to be about a pound a day. I think you put five back on with water and bowel retention once you refeed. I lost 39 over 40 days and I’m currently refeeding, so I’ll let you know how much comes back on.

Answer

That is easy to estimate.1 kg of fat equals to 7700 kcals. You need 2000 to stay neutral if you don’t exercise. Ergo 7 days of fasting will ‘earn’ you a negative of 14000 which roughly equals 2 kgs per week.

However.

You will be loosing a lot of water to a point. 1 molecule of fat requires 3 molecules of water to be broken down. That means for every kilo of fat you will lose 3 Liters of water. That only includes the water needed to burn fat (by fat I mean lipolysis, breaking down triglycerides. Burning the palmitic acid requires 16 molecules of water per one fatty acid molecule).

Then there is the increasing metabolic rate that will burn calories faster. You will peak at day 8-12. If you work out or just tak 2x1 hour walk a day your daily negative will be -3000 kcal.

Sleeping gets you additional -722 kcal at your weight. Meaning if you walk atleast 10.000 steps a day at a working BPM 100-135 you will start losing 0.5 -0.7 kg fat per day.

Ofcourse this is a rough estimation that surprisingly worked for me perfectly. In 24 days I lost 16 kgs of fat mass (24 kgs in total. Some of which returned back during refeeding). In my case the loss stayed consistent for 8 years until the pandemic where I gained 15 kgs back (I was not in a great mental place, go.figure)

Answer

You can expect to lose as much as you do if you actually do it. Prolonged water fasting is some seriously tough shit especially if you’re new to it overall. There are so many variables to consider and none of us can/should try to figure this out for you.

Also idk how it hasn’t been mentioned here already, but 6’1” and 150lbs…. In no way is that an appropriate or healthy weight for that height.

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