Sleep Biomarkers
Tracking my sleep 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
RBC Magnesium
RBC Magnesium, mg/dL
Jan 27, 2023 - 5.5
Jun 30, 2023 - 4.8
Dec 17, 2024 - 5.7
Feb 11, 2025 (9-day fast) - 5.8
Sep 4, 2025 (10-day fast) - 5.3
Oct 14, 2025 - 5.3
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
Magnesium
Magnesium, mg/dL
Jan 27, 2023 - 2.0
Jun 30, 2023 - 2.0
Dec 17, 2024 - 2.2
Feb 11, 2025 (9-day fast) - 2.1
Sep 4, 2025 (10-day fast) - 2.0
Oct 14, 2025 - 2.1
Vitamin D
Vitamin D, ng/mL
Jan 27, 2023 - 26
Jun 30, 2023 - 47
Dec 17, 2024 - 32
Feb 11, 2025 (9-day fast) - 47
Sep 4, 2025 (10-day fast) - 57
Oct 14, 2025 - 42
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
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
hsCRP
hsCRP, mg/L
Jan 27, 2023 - 0.3
Jun 30, 2023 - 0.3
Dec 17, 2024 - 0.2
Feb 11, 2025 (9-day fast) - 0.2
May 27, 2025 - 0.2
Sep 4, 2025 (10-day fast) - 0.2
Oct 14, 2025 - 0.3
Testosterone, ng/dL
Jun 30, 2023 - 821
Dec 17, 2024 - 969
Feb 11, 2025 (9-day ) - 131
May 27, 2025 - 564
Aug 25, 2025 - 671
Sep 4, 2025 (10-day fast) - 495
Oct 14, 2025 - 882
White Blood Cells
WBC, thousands/uL
Jan 27, 2023 - 3.8
Jun 30, 2023 - 3.4
Dec 17, 2024 - 3.7
Feb 11, 2025 (9-day fast) - 3.4
Sep 4, 2025 (10-day fast) - 3.1
Oct 14, 2025 - 3.8
Testosterone
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