Testy

Měření a testy

Serum paraxanthine

• Useful for distinguishing varying caffeine intakes [12]
• Pearson correlation coefficients between self-reported caffeine intake and serum paraxanthine concentrations (0.50–0.53)
• Were comparable to reported correlations between cigarette smoking and serum cotinine concentrations

Urinary caffeine metabolites

• 1-methylxanthine
• 1,7-dimethyluric acid
• May also be useful for assessing dietary caffeine intake

Chlorogenic acid or its metabolites

• May also contribute to the health effects of coffee
• Reliable biomarker for coffee-derived polyphenol intake would be useful [12]

Isoferulic acid

• Specific metabolite of dietary caffeic acid derivatives
• Less than 7% of the variance in coffee intake was explained by urinary isoferulic acid excretion
• Limited usefulness as a biomarker for coffee-derived polyphenol exposure [12]