Cognition Biomarkers
Tracking my cognition biomarkers across 2.5 years of fasting – including results from my 7-, 9-, and 10-day water fasts.
The end of the 10-day fast - Sep 4, 2025
After 40 days of refeeding - Oct 14, 2025
Cortisol
Cortisol, µg/dL
Jan 27, 2023 - 14
Jun 30, 2023 - 13.7
Dec 17, 2024 - 10.8
Feb 11, 2025 (9-day fast) - 14.1
May 27, 2025 - 8.5
Sep 4, 2025 (10-day fast) - 18.5
Oct 14, 2025 - 10.8
Glucose
Glucose, mg/dL
Jan 27, 2023 - 88
Jun 30, 2023 - 89
Dec 17, 2024 - 88
Feb 11, 2025 (9-day fast) - 64
Sep 4, 2025 (10-day fast) - 63
Oct 14, 2025 - 88
HbA1c
HbA1c, %
Jan 27, 2023 - 5.5
Jun 30, 2023 - 5.5
Dec 17, 2024 - 5.5
Feb 11, 2025 (9-day fast) - 5.3
Sep 4, 2025 (10-day fast) - 5.3
Oct 14, 2025 - 5.4
Insulin
Insulin, µIU/mL
Dec 17, 2024 - 2.8
Feb 11, 2025 (9-day fast) - 0.2
May 27, 2025 - 1.4
Sep 4, 2025 (10-day fast) - 1.5
Oct 14, 2025 - 3.6
Vitamin B12
Vitamin B12, pg/mL
Jan 27, 2023 - 580
Jun 30, 2023 - 472
Dec 17, 2024 - 520
Feb 11, 2025 (9-day fast) - 1,548
May 27, 2025 - 529
Sep 4, 2025 (10-day fast) - 1,605
Oct 14, 2025 - 400
Folate
Folate, ng/mL
Jan 27, 2023 - 12.6
Jun 30, 2023 - 12.9
Dec 17, 2024 - 18.8
Feb 11, 2025 (9-day fast) - 19.4
May 27, 2025 - 18.8
Sep 4, 2025 (10-day fast) - 16
Oct 14, 2025 - 18.8