Nutritionist have usual warn us against drinking juice because processing fruit into juice loses most of the fiber, often
adds sugar, and damages some of the nutrients that make fruit such a
healthy choice. But a recent study
published in the Journal
of Agricultural and Food Chemistry found that juicing may
improve how readily certain nutrients can be absorbed by the body.
The researchers compared the carotenoid, flavonoid and vitamin C
concentrations in fresh orange segments, homogenized orange puree and
orange juices that varied in processing (freshly squeezed, pasteurized and
flash-pasteurized). They reported that
the content of some carotenoids and flavonoids decreased with juicing,
while the vitamin C content was unaffected. They also evaluated the bioaccessibility (the fraction of the compound
that is released from the food matrix in the gastrointestinal tract that is
available for intestinal absorption) of these bioactives. Compared to
orange segments or puree, the bioaccessibility of carotenoids increased
three- to four-fold in the orange juices. For flavonoids, there was a four-
to five-fold increase and the increase for vitamin C was approximately
10%.
Consumers perceive orange juice as a healthy source of vitamins and other
health-promoting nutrients, the researchers noted, and juice offers
convenient packaging and long shelf life. Recent intervention studies have
shown health benefits of long-term orange juice consumption, including
increased total antioxidant status, lower total cholesterol levels, and the
prevention of increases in toxic compounds after meals high in fat and
carbohydrate. The researchers added, "However, greater consumption of
orange juice has also been criticized because of its high intrinsic sugar
level, being associated with a higher risk of type 2 diabetes and
cardiovascular diseases."
What’s a confused consumer to do? The finding that juicing makes certain
nutrients more available is certainly a plus, since dietary carotenoids,
flavonoids and vitamin C have been associated with decreased risk of
certain diseases.
For most consumers, the fiber and pectin lost in juicing still overrides
any minor benefits in bioaccessibility. According to the USDA's Nutrient
Database, one cup of orange juice contains less than a gram of dietary
fiber (0.7 gram), while a cup of orange segments has 4.3 grams of fiber.
Beware, too, of orange juice beverages that contain added sugar (and often
not much actual juice).
Those who have interest in their
intakes of pectin and fiber may wish to consider oranges and orange puree.
When considering sugar content, there is no difference between fresh
oranges versus pure orange juice. All foods evaluated can be considered as
a good-to-rich source of vitamin C.
This article was adapted from Tufts Health & Nutrition Letter: Oranges vs. Orange Juice: Which Is Better? January 25, 2016
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