Neutrophil to Lymphocyte Ratio (NLR)
Haematology marker
Neutrophil to Lymphocyte Ratio
Neutrophil to Lymphocyte Ratio (NLR)
The absolute neutrophil count divided by the absolute lymphocyte count. It is a simple, inexpensive index of systemic inflammation and physiological stress derived from a standard full blood count. A higher ratio reflects a shift toward innate (neutrophil) immunity and away from lymphocytes, a pattern seen with inflammation, infection, and stress.
PED Notes
A useful low-cost gauge of systemic inflammation and training stress in athletes, best read as a trend rather than a single value. Hard training, overtraining, and acute physical or psychological stress raise the ratio through a cortisol-driven neutrophilia plus lymphopenia; it typically normalises within a day of rest, so use a rested, non-post-workout draw. It is not directly altered by AAS, but a persistently elevated NLR in an enhanced athlete can flag chronic inflammation or under-recovery worth investigating alongside CRP. Values are only meaningful when both the neutrophil and lymphocyte counts are themselves valid, so always interpret it with the full differential.
When high
When elevated (systemic inflammation / stress):
- Read alongside the absolute neutrophil and lymphocyte counts and CRP or ESR before drawing conclusions
- Common benign drivers in athletes: a post-exercise or overtraining stress response, acute infection, and poor sleep; recheck on a rested day
- A persistently raised NLR (roughly >3) without an obvious acute cause warrants a look for chronic inflammation, and in the general population is associated with worse cardiovascular and other outcomes
- Address the cause rather than the ratio: manage training load and recovery, resolve any infection, and reduce systemic inflammation (sleep, omega-3s, treating the underlying driver)
- No supplement or drug targets the NLR directly; it moves when the underlying inflammatory state improves
When low
When low:
- A low NLR (a relatively high lymphocyte share) is generally not a concern in a well person
- Interpret alongside the full differential; a very low ratio driven by neutropenia or a markedly high lymphocyte count should be assessed via those absolute counts, not the ratio
History Chart
Reading History
Frequently Asked Questions
Reference Ranges
Standard Range
VitalMetrics Range