 While
solid proof linking spinach to bulging forearms is still
missing, Popeye's obsession with the leafy veg may not
be completely unfounded. A growing body of evidence indicates
that spinach may have other health benefits. A study published
in the December issue of the Journal of Nutrition
confirms that carotenoids from leafy dark green vegetables
like spinach, collard greens and kale can help prevent
cataracts.
Human eyes contain two carotenoid
molecules, lutein and zeaxanthin, which function as
antioxidants. Despite the fact that many over-the-counter
vitamin pills and leafy green veggies include these
molecules, until now there was no biochemical evidence
to support the assumption that they help maintain ocular
health.
"Our results are the first to provide
physical evidence suggesting that lutein and zeaxanthin
decrease damage caused by ultraviolet radiation," said
author Dr Joshua Bomser of Ohio State University.
This is big news because ultraviolet
(UV) rays wreak havoc in the epithelial layer of the
lens by creating free radicals that damage cellular
components. This eventually kills the cells and cataracts
form as these dead cells clutter up the lens, rendering
it opaque.
CELLULAR
TAN
The study looked at what happened to cultured human
lens epithelial cells in the presence of UV light. The
cells were incubated with the concentrations of lutein
and zeaxanthin normally present within the eye and then
exposed to UV light strong enough to induce a light
tan. Cells containing lutein and zeaxanthin were less
damaged by radiation exposure and didn't start up their
stress response systems as frequently as the control
cells. The test cells also contained fewer peroxidated
lipid molecules, which are the result of a chemical
reaction that occurs when free radicals are loose in
the cell.
The researchers are still curious
as to how the carotenoids ingested in the diet make
their way into the lens because the eye has no vascular
system to transport nutrients. Future work will focus
on unravelling that mystery.
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