New Laboratory Focuses on Foods That
November 25, 1997
Compounds in fruits, vegetables, soybeans, nuts, grains and tea that appear
to promote health will get the undivided attention of five scientists in a new
Laboratory at the Beltsville Human Nutrition
Research Center. The center is part of the
Agricultural Research Service, the
U.S. Department of Agricultures chief
Carotenoids like beta carotene are one group of the compounds called
phytonutrients, and we need to know more about phytonutrients and their
importance for health, said
Kennedy, USDAs deputy under secretary of agriculture for research,
education and economics. Scientists at the new Phytonutrients Laboratory
will focus on whether and how phytonutrients in whole foods such as fruits and
vegetables contribute to health in ways we havent known about.
The new laboratory includes four scientists, already with the center, who
earlier pooled their talents to assess the nutritional effects of carotenoids,
including beta carotene, lycopene and lutein. The four scientists determined
the extent to which these phytonutrients are absorbed from foods as well as if
and how they promote health. The center will hire a fifth researcher, one with
a background in phytonutrients.
"We knew we were interested in more than just carotenoids," said
nutritionist Beverly Clevidence, who led the earlier studies and will head the
new laboratory. It's an exciting and rapidly growing area. The
field is so new that Clevidence and her colleagues must develop methods for
identifying and measuring various phytonutrients before they can study the
effects these substances have on the human body.
"What we know about phytonutrients is what was known about vitamins
early in this century," said Clevidence. Scientists then knew they
could keep rats alive by adding egg yolk or liver to a diet that otherwise
would not sustain the animals. The scientists didn't know what components in
egg yolks or liver kept the animals alive. Only later did they discover that
these components were vitamins essential to life.
Unlike vitamins, phytonutrients may not be essential for life, but
researchers believe they may be important for optimal health. We know
that fruits, vegetables and probably soy and some grains are important for
health, Clevidence said. But we don't know all the health-giving
components in these foods yet. And science is only beginning to determine how
Deciphering the exact role of phytonutrients wont be easy, she added.
Many scientists think these components act in concert with one another.
This adds a new level of complexity to the research."
It may also explain why some study participants who took beta carotene
supplements did not show a change in risk for chronic diseases. Clevidence said
it's human nature to look for one substance--a magic bullet--that
keeps people healthy, but that's unrealistic. Humans evolved eating whole
foods, not purified supplements.
"We will emphasize whole foods and want to know if a food or class of
foods promotes health and how it works, she said.
Clevidence said one of the new laboratory's first studies will focus on
almond flour. Almonds and nuts in general appear to be a rich source of
phytonutrients. The Beltsville researchers want to know how well these
substances are absorbed by the body and how long it takes after eating for
blood levels to peak.
Another project will focus on measuring black teas
phytonutrients--known as catechins--that may have antioxidant properties.
Later, the researchers will measure catechins in blood plasma.
ARS will sponsor a workshop next March aimed at increasing research on
phytonutrients and health nationwide. The agency plans to invite approximately
75 plant and nutrition scientists to discuss ways of increasing phytonutrients
in commonly eaten foods.
Scientific contact: Beverly A. Clevidence, PhD, nutritionist and
research leader, Phytonutrients Laboratory, Beltsville Human Nutrition Research
Center, Agricultural Research Service, USDA, Beltsville, Md., telephone (301)
504-8367, fax (301) 504-9098, email@example.com