I (M23) am 6’4 and weigh 370 lb - that’s pretty obese. In the past, I’ve done extended water fasts, the longest being 4 days and pretty much I always lost 3 lb per day.
I’ve seen a few posts here from people who are less obese than me, in particular one woman, who lost 50 lb in an 18 day fast.
Which is why I’m confident in my plan to lose 90 lb in 45 days, by performing consecutive rolling 72s from 30th January -> 15th March.
On the days that I do break the fast, I will do strict keto OMAD with lots of protein. I’ll also exercise only on the first day of each 72 hour fast, by doing a light 2 mile walk.
And I know that once I start eating normally again, I’ll gain weight due to the re-feed.
I guess what I’m asking is if anyone in a similar boat to me has had any success with what I’ve described, what your experience was like, and how much weight you lost. There will be times where I’ll exceed the 72 hours and go a little longer, but for the most part it’ll be rolling 72s.
And I want to exclaim that I know that I’d have to lose at least 2 lb every single day to achieve this, which sounds like a lot, but remember I have a BMI of 46.
Check a TDEE calculator and do the math. There are 3500 calories in a pound of fat, give or take. If you burn that much in a day, you’ve lost a pound. If you burn that much in two days, then you’ve lost 0.5 lbs in one day.
This a LOT of weight to lose in a fairly short period of time. Rapid weight loss can have some severe side effects such as hair loss, gallstones, and lean muscle loss.
I would highly recommend seeking the advice and/or supervision of a medical professional before attempting to lose that much that quickly.
You won’t lose 3 pounds a day. Fully fasting at your weight and height if you’re sedentary you can expect 1 pound of actual fat loss per day to start. You’ll lose a lot of water weight as well which gives the illusion you’re losing more fat than you actually are. The moment you eat you’ll see a bunch of the water weight return. This will of course slow down as you lose weight. For example at 250 pounds this would slow to .6 to .75 of a pound per day.
That being said 1 pound a day is pretty rapid weight loss. If you’re doing rolling fasts over 45 days a more realistic weight loss expectation is closer to 30-40 pounds depending how much exercise you do on top of it. That’s still a fantastic amount of weight to lose in 45 days.
If you’re in it for the long haul you could also try something more sustainable to achieve similar results but not fasting. For example eating an 1,800 calorie per day diet high in protein over the same length of time would achieve a very similar result at your weight.
One thing you are not factoring in is that you have a BMI of 46…until you don’t have a BMI of 46. As you lose weight, your weight loss rate will decrease and if you go far enough it will plateau but likely not at the high rate you want.
I’m not completely convinced that your plan is feasible, but if you’re gonna make that pace then I think you should consider adding in more LISS cardio.
Normally I would’t consider a 2 mile walk as “exercise” but since you are like 370 then I can see it. For you to hit 2lb of legit fat loss per day then you are going to have to add more. I would suggest ya walk the 2 miles at least daily, no matter how slow you have to go. But at 370 I am concerned for your knees. Do you have access to a recumbent bike or stationary bike or swimming pool instead? Even the laziest swim torches huge piles of calories and there is zero stress on your knees.
It mostly comes down to how much muscle mass you have but yeah very doable. I lost 60lbs in 60 days doing just strict keto and I started at the same weight as you. I’m only an inch taller so I doubt that mattered much.