What
are goji berries?
Other
Names: Lycium barbarum, wolfberry, gou qi zi, Fructus
lycii
Goji berries grow on an evergreen shrub found in
temperate and subtropical regions in China, Mongolia and in the
Himalayas in Tibet. They are in the nightshade (Solonaceae)
family.
Delicious
added to your cereal or yogurt.
Goji berries are
usually found dried. They are shriveled red berries that look like
red raisins. Some folks like them reconstituted with hot water
first.
Why
do people use goji berries?
Goji
berries have been used for 6,000 years by herbalists in China, Tibet
and India to:
·
protect
the liver
·
help
eyesight
·
improve
sexual function and fertility
·
strengthen
the legs
·
boost
immune function
·
improve
circulation
· promote longevity
-
High in vitamin A
Goji
berries are rich in antioxidants, particularly carotenoids such as
beta-carotene and zeaxanthin. One of zeaxanthin's key roles is to
protect the retina of the eye by absorbing blue light and acting as
an antioxidant. In fact, increased intake of foods containing
zeathanthin may decrease the risk of developing age-related macular
degeneration (AMD), the leading cause of vision loss and blindness
in people over the age of 65.
In recent years, goji juice has
become popular as a health beverage. Companies marketing goji juice
often mention the unsupported claim that a man named Li Qing Yuen
consumed goji berries daily and lived to be 252 years old. Marketers
also list extensive health benefits of goji juice, even though there
are few published clinical trials in humans.
What
research has been done on goji berries?
Goji
has only been tested on humans in two published studies. A Chinese
study published in the Chinese Journal of Oncology in 1994 found
that 79 people with cancer responded better to treatment when goji
was added to their regimen.
There have been several test
tube studies that show that goji berry contains antioxidants and
that goji extracts may prevent the growth of cancer cells, reduce
blood glucose, and lower cholesterol levels. However, that doesn't
necessary mean that goji will have the same benefits when taken as a
juice or tea.
Although goji berries like the ones used in
traditional Chinese medicine aren't very expensive, goji juice is
very pricey. Considering that a 32-ounce bottle of goji juice (about
an 18-day supply) can run as high as $50 USD, the evidence isn't
compelling enough at this time to justify the cost of goji juice.
Also, we don't know the side effects of regular goji
consumption, or whether it will interfere with treatments or
medications.
What
do goji berries taste like?
Goji
berries have a mild tangy taste that is slightly sweet and sour.
They have a similar shape and chewy texture as raisins.
Common
forms
In
traditional Chinese medicine, goji berries are eaten raw, brewed
into a tea, added to Chinese soups, or made into liquid
extracts.
Goji juice is also available, usually in 32-ounce
bottles.
Goji berries have appeared in snack foods in North
America. For example, the health food store Trader Joe's sells a
goji berry trail mix.
Possible
drug interactions
Goji
berries may interact with anticoagulant drugs (commonly called
"blood-thinners"), such as warfarin (Coumadin®). There was one case
report published in the journal Annals of Pharmacotherapy of
a 61-year old woman who had an increased risk of bleeding, indicated
by an elevated international normalized ratio (INR). She had been
drinking 3-4 cups daily of goji berry tea. Her blood work returned
to normal after discontinuing the goji berry tea.
Where
to find goji berries
Goji juice can be found in some health food stores, online stores, and through network marketers.
Sources
Cheng CY et al. "Fasting plasma zeaxanthin response to Fructus barbarum L. (wolfberry; Kei Tze) in a food-based human supplementation trial." British Journal of Nutrition. 93.1 (2005):123-30.
Lam AY et al. "Possible interaction between warfarin and Lycium barbarum L." Annals of Pharmacotherapy. 35.10 (2001):1199-201.
Wu H et al. "Effect of Lycium barbarum polysaccharide on the improvement of antioxidant ability and DNA damage in NIDDM rats." Yakugaku Zasshi. 126.5 (2006):365-71