#Note/Permanent #Nutrition/Caffeine/Tolerance
## Concept of Caffeine Tolerance
Humans can develop a tolerance[^1] to caffeine, meaning habitual consumers may become less sensitive to some of its effects, particularly in terms of mood and cognitive performance enhancement.
## Mechanism of Tolerance Development
As explained on [Wikipedia](https://en.wikipedia.org/wiki/Caffeine_dependence#Dependence), continued caffeine exposure leads to an increase in the number of [[Understanding Adenosine and Its Role in Sleep|adenosine receptors]] in the central nervous system. This makes the system more sensitive to adenosine, reducing the stimulatory effects of caffeine by increasing tolerance.
## Research Insights on Caffeine Tolerance
- **Low-Dose Tolerance**: According to research[^2], chronic ingestion of even low doses (<75mg/day) of caffeine can still lead to tolerance in individuals who are regular caffeine consumers.
- **Persistence of Some Benefits**: Despite the development of tolerance, caffeine continues to provide certain benefits. Research[^3] indicates that even after daily consumption for 20 days, caffeine still offers a beneficial effect, though not large, on performance or endurance compared to a placebo. This implies that the performance benefits of caffeine are not completely negated by tolerance.
- **Benefits are Inherent**: Further studies[^4] suggest that caffeine's benefits for mood and cognitive function are inherent and not merely due to the relief of withdrawal symptoms in regular consumers.
[^1]: [Caffeine Tolerance and Choice in Humans](https://pubmed.ncbi.nlm.nih.gov/1410146/)
[^2]: [Chronic Low Dose Caffeine Tolerance](https://www.tandfonline.com/doi/full/10.1080/02640414.2016.1241421?scroll=top&needAccess=true)
[^3]: [Caffeine's Effectiveness on Performance After 20 Days](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6343867/)
[^4]: [Caffeine and Cognitive Function](https://link.springer.com/article/10.1007/s00213-004-2104-3)