NfL (Neurofilament Light Chain)
Neurofilament light chain (NfL) is a structural protein released into the blood when nerve axons are damaged. A longevity practice tracks this emerging marker because rising levels signal ongoing neurodegeneration across conditions from Alzheimer's to multiple sclerosis, and can reflect overall brain aging.
What It Measures
Axonal damage marker in plasma.
Optimal vs. Lab Range
Target range for optimal health and longevity based on research.
Population-based reference range from standard labs.
Why It Matters
Rising NfL signals neurodegeneration (MS, AD, ALS, TBI).
When Low
—
When Optimal
Low → no significant neuronal injury.
When High
Elevated → ongoing neurodegeneration; workup indicated.
How to Optimize
Aerobic exercise, sleep, BP/glucose control, treat underlying disease.
Key Interventions & Linked Compounds
Strong (9/10)Key Interventions
Linked Compounds & Supplements
Curated from clinical literature. Individual results vary; consult a qualified clinician before changing a protocol.
Ordering Notes
Specimen
Serum or plasma (venous draw)
Patient prep
No fasting required. Maintain usual diet and medications unless advised.
Recommended cadence
Re-test every 3–6 months when actively optimizing; annually for monitoring.
Reporting unit
pg/mL
Pre-analytic notes
Standardize draw time of day, hydration, and recent exercise. Note any acute illness, supplements, or hormonal therapies on the requisition.
Recommended Follow-Up Actions
- 1
Confirm the result is reliable
Repeat abnormal values before acting — preferably from the same lab, same time of day, and under consistent prep. Rule out acute illness, recent intense exercise, or medication effects that can shift NfL (Neurofilament Light Chain).
- 2
Compare against optimal, not just lab range
Use the optimal window above as the target. Lab "normal" is built from the general population and often misses early dysfunction.
- 3
Pair with related markers
Order a complementary panel covering metabolic, inflammatory, and hormonal context to interpret this marker properly.
- 4
Discuss interventions with a clinician
Use the interpretation guidance above to frame the conversation. Bring trends, not just one datapoint, to your visit.
- 5
Re-test on a defined cadence
If a change is implemented, re-measure in 8–12 weeks for fast-moving markers, or 3–6 months for slower ones, to confirm response before escalating.
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