body and brain against aging.
Carotenoids—the yellow, orange, and red pigments
abundant in carrots, sweet potatoes, rhubarb, and
particularly in dark leafy greens like kale and spinach—
have been identified as powerful brain boosters (you can’t
see them in dark leafy greens because they’re disguised by
the green pigment of chlorophyll—but they’re there).
Among these, lutein and zeaxanthin in particular have been
linked with greater neural efficiency and “crystallized
intelligence,” or the ability to use the skills and knowledge
one has acquired over a lifetime.^42
TURBOCHARGE YOUR BRAIN WITH
CAROTENOIDS
It’s been known for some time that carotenoids play an
important role in protecting the eyes and brain from aging,
but they may also speed up your brain. In a clinical trial,
University of Georgia researchers gave sixty-nine young,
healthy male and female students supplements containing
lutein and zeaxanthin—two carotenoids abundant in kale,
spinach, and avocado—or a placebo for four months. The
subjects who received the lutein and zeaxanthin saw a 20
percent boost in visual processing speed, measured by the
retina’s automatic reaction to a stimulus. Processing speed is
important because it’s the pace at which you take
information in, make sense of what you are perceiving, and
begin to respond. Faster visual processing tends to correlate