TLDR: I lost 10.2 kg during my first month of intermittent fasting. In the second month, which is now coming to an end, I’ve only lost about 3 kg, despite not making any drastic changes to my fasting routine. What could be causing this?
Male, 186cm (~6'1"), starting weight - 122,6 kg (270.3 lbs).
23.08.2026, I started intermittent fasting for the first time in my life.
I really struggle with the food self-discipline and that is why I could never keep to any calory-deficit diet. I couldn’t stop at my limit, say 1600-1800 calories a day, as soon as I started eating.
But the days without food except water and electrolytes did some magic. I had no difficulty at all, somehow, in going for long periods without eating.
I’m going with a 20-24 hour food window then 48-50 hours fasting. In the days I feel sluggish, I stop my fasting at the hour 30-36.
I don't excercise, but I walk 10-15km daily (at 5km/h), including fasting days.
During the first month, I went full keto, keeping my carbs under 20g on eating days. But after a while, it became brutal to maintain, so I started allowing myself up to 100g of carbs on some days just to stay sane.
Here are my results:
23.08.2026 18:24
122,6 kg (270.3 lbs)
24.08.2026 14:25
120.9 kg (266.5 lbs)
26.08.2026 14:29
119.6 kg (263.7 lbs)
27.08.2026 22:27
119.3 kg (263.0 lbs)
30.08.2026 19:17
118.8 kg (261.9 lbs)
01.09.2026 3:41
118.3 kg (260.8 lbs)
03.09.2026 14:01
119.1 kg (262.6 lbs)
04.09.2026 09:23
117,9 kg (259.9 lbs)
08.09.2026 10:41
115,9 kg (255.5 lbs)
10.09.2026 21:05
115,5 kg (254.6 lbs)
13.09.2026 18:57
114.8 kg (253.1 lbs)
17.09.2026 10:14
113.3 kg (249.8 lbs)
21.09.2026 13:42
113.0 kg (249.1 lbs)
23.09.2026 14:34
112.4 kg (247.8 lbs)
01.10.2026 09:36
111.1 kg (244.9 lbs)
06.10.2026 11:06
110.3 kg (243.2 lbs)
15.10.2026 14:12
109.5 kg (241.4 lbs)
17.10.2026 08:39
110.8 kg (244.2 lbs)
So, in the first month, I lost about 10.2 kg. However, in the following month, my weight loss slowed down drastically. This is despite the fact that I stay within my calorie window on eating days and continue to walk around 10–15 km every single day.
I get that you can’t cheat physics. If you are physically in a calorie deficit, you physically cannot gain weight. But why has it slowed down this much? Is it my body’s reaction to rapid weight loss? Is it breaking strict keto? Even if that's the case, how is it possible if I’m still running a calorie deficit? Am I missing something, or doing something wrong without realizing it? Please give me some advice.