In 2017, IAFNS published a large Systematic Review of caffeine and 5 adverse health outcomes.  Explore the background, methods, findings and related resources on this page.

This systematic review was selected as the “Best Paper of the Year” for 2017 by the editors of Food and Chemical Toxicology.

Why review caffeine safety?

Since 2003, more than 10,000 papers have been published related to caffeine, half of which address effects or exposure levels in humans. In addition, more than 800 reviews related to various human health effects and caffeine have been published, but a robust, transparent and systematic assessment of five adverse health effects associated with caffeine consumption was not available in the peer-reviewed research until now.

This Systematic Review looked at five adverse health outcomes associated with caffeine consumption and over 2 dozen specific endpoints related to caffeine in the areas of:

  • acute toxicity
  • cardiovascular effects
  • bone and calcium
  • behavior
  • reproductive & development toxicity

The manuscript


  • Conducted systematic review of the potential adverse effects of caffeine consumption in healthy populations
  • Included evaluation of cardiovascular, behavioral, reproductive & developmental, bone & calcium, and acute effects
  • Evidence supported consumption of ≤400 mg/day in adults is not associated with overt, adverse effects
  • Intakes of ≤300 mg/day in pregnant women and ≤2.5 mg/kg-day in children and adolescents remain appropriate recommendations
  • Findings support shift in future research to unhealthy populations, sensitive populations and interindividual variability

This paper is robust and transparent, allowing for others to see all the data that helped inform the conclusions.  This data can be used for future research. Protocols for each of the five outcomes were published for public review prior to implementation of the review.   All data extracted from the review were placed in a freely available Agency for Healthcare Research and Quality (AHRQ) Systematic Review Database Repository (SRDR) repository.  Both of these resources are accessible below. 

Open data and transparency