I'm going to show you something I haven't shown anyone. My mood scores from 30 days of fasting.
Every day at 9 PM, I rated my mood from 1 to 10. Same time, same question: "How do you feel right now?" No overthinking. First number that came to mind.
The results are... weird.
Week 1 (days 1-7): Average mood 6.2. Not great. I was adjusting to 18:6, dealing with hunger pangs, and honestly a little irritable. Day 3 was a 4 — I snapped at my roommate over dishes. Not my finest moment.
Week 2 (days 8-14): Average mood 7.1. Better. My body was adapting. The hunger wasn't as sharp. I started noticing the mental clarity people talk about. Day 11 was an 8 — I had this productive design session that just flowed.
Week 3 (days 15-21): Average mood 7.8. This is where it got interesting. I was consistently hitting 18+ hours. My sleep improved (I track that too, because of course I do). I woke up feeling actually rested. Day 17 was a 9 — I don't even know why, I just felt good all day.
Week 4 (days 22-30): Average mood 7.5. Slight dip from week 3, but still way above week 1. Day 24 was a 5 — I had a bad work day and broke my fast early with ice cream. Emotional eating, classic. Day 28 was a 9 again — hit a new personal record of 20 hours.
So what does this mean? I don't know for sure. Correlation isn't causation. Maybe I was just having a good month. But the trend is hard to ignore: as my fasting consistency improved, so did my mood. Not perfectly, not linearly, but definitely upward.
The drop on day 24 is important though. It shows that breaking my protocol didn't just affect my weight — it affected my mental state. I felt guilty, frustrated, like I had undone progress. Even though one day of ice cream literally doesn't matter metabolically, it mattered psychologically.
That's something I don't see talked about enough. The mental game of fasting. It's not just physical hunger. It's the discipline, the routine, the identity of being "someone who fasts." When you break that identity, even for a day, it hits different.
I made a chart of this data. It's not pretty — I used my calculator's trend tracking tab, which is basically a bar chart made of CSS divs. But I can see the pattern. And that's what matters.
If you're fasting and feeling moody in the first week, hang in there. Week 2 was better for me. Week 3 was actually good. Your brain is adapting, just like your body. Give it time.