Table 3: Excreted amount of hydroxytyrosol and homovanillic acid at baseline (pre) and end of intervention (post) for the three intervention periods.

Pure hydroxytyrosol Olive extract Placebo
Variable Pre Post Pre Post Pre Post
Homovanillic acid
(µg/8 h urine)
247.2 (± 371.6) 4168.0 (± 2355.8) 365.1 (± 760.7) 3921.5 (± 2211.9) 292.0 (± 526.3) 314.1 (± 500.5)
Hydroxytyrosol (µg/8 h urine) < LoD 744.4 (± 547.4) < LoD 791.1 (± 562.6) < LoD 16.3 (± 87.9)

Data points are mean ± SD.