Coffee consumption is highest in Scandinavian countries,17
making caffeine or coffee consumption an attractive candidate
as a modifiable lifestyle risk factor in ES and EG. Coffee
consumption has been shown to increase plasma homocysteine
(Hcy) levels in several randomized clinical trials.18–20 Hcy
levels in plasma,21–26 aqueous humor,27 and tear fluid28 are
consistently elevated in ES patients compared to those in
control subjects. Elevated Hcy may enhance exfoliation
material formation by contributing to vascular damage,29
oxidative stress,30,31 and extracellular matrix alterations.32
Noncaffeine components in coffee may be responsible for
increased Hcy levels,33,34 although the exact mechanisms
involved are unclear. While coffee consumption can also lead
directly to modest, transient elevations in IOP,35–38 it is unlikely
that caffeine’s effect on aqueous humor dynamics contributes
to the ocular accumulation of exfoliation material and
subsequent EG.