Paragraph 2
Thirty-four adults took part in the
. Half of them ate grapes every
; the other
ate a placebo
. None of them knew if the tests were on the grapes or the snack. This gave better test
. The people who ate the grapes had better muscle
around the retina. The retina sends
about light to the brain. It protects the eyes from
light, which damages the
. A lot of blue light comes from
screens.