Food & Nutrition Research Briefs, April 2006
Rich sources of copper include nuts, sunflower
seeds, lobster, green olives, wheat bran, liver, blackstrap molasses, cocoa,
oysters and black pepper.
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Eating foods that provide, by days end,
about three times the recommended daily amount of copper may help overweight or
obese women retain calcium in their bones while theyre dieting.
That's indicated by a study with overweight
women aged 25 to 35.
Some of the women in the study received daily
supplements of 3 milligrams (mg) of copper. The others received supplements of
only 1.23 mg.
All participants were then put on a
weight-loss diet for four months.
Women who took 3 mg of copper retained more
calcium in their bones than those who took 1.23 mg of supplemental
copper.
The current Recommended Dietary Allowance for
copper is 0.9 mg for women older than 19 years.
The copper study, conducted by scientists at
the ARS Grand Forks (N.D.) Human Nutrition Research Center, suggests the
current allowance for copper may not be adequate during weight loss.
For details, contact:
Henry
C. Lukaski, (701) 795-8429; USDA-ARS
Grand
Forks Human Nutrition Research Center, Grand Forks, N.D.
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Principal dietitian Jeanne Blankenship (left) and
doctoral student Tara Hembrooke review the dinners for the whole- and
refined-grains study.
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Whole-grain foods like crunchy, whole-wheat
toast are already known to help keep the body's levels of certain fats in
check. A preliminary study by scientists with the Agricultural Research
Services Western Human Nutrition Research Center, Davis, Calif., suggests
whole-grain foods might do that by affecting VLDLs, or very-low-density
lipoproteins, that transport fat in the blood.
For the investigation, 10 healthy female
volunteers, aged 20 to 45, completed a short stint featuring whole-grain foods,
and another featuring refined-grain selections.
Each stint was followed by a test breakfast
at the laboratory. Volunteers gave a blood sample before breakfast and at three
intervals later in the day.
Scientists found two significant differences
in VLDLs. First, volunteers' VLDLs had higher levels of a kind of fat, known as
a triglyceride, following the refined-grains test breakfast than following the
whole-grains test meal.
Second, volunteers' VLDLs had a higher amount
of another worrisome compoundthis one known as apoCIII (short for
apolipoprotein CIII)following the refined-grains breakfast.
In medical studies, higher levels of
triglycerides and of apoCIII have been associated with higher risk of heart
disease.
A longer, larger followup study is planned
for later this year.
For details, contact:
Nancy
L. Keim, (530) 752-4163; USDA-ARS
Western
Human Nutrition Research Center, Davis, Calif.
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Most Americans eat less than a single serving a
day of whole-grain foods.
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Older adults who ate nearly three servings of
whole-grain foods daily were significantly less likely to die from heart
disease than those who ate fewer servings.
Thats according to a study conducted by
researchers at the ARS Jean Mayer USDA Human Nutrition Research Center on Aging
at Tufts University, Boston, Mass., and their colleagues, and published in the
January 2006 issue of the American Journal of Clinical Nutrition (volume
83, pages 124 to 131).
They based their findings on their 1981-1984
analysis of three-day food records and blood tests from 535 healthy male and
female participants older than 60, and their 12- to 15-year follow-up to assess
the causes of death among participants during those years.
When sorted into groups according to the
amount of whole-grain foods they ate, those who ate the mostan average of
about 2.9 servings a dayhad significantly less risk of dying from heart
disease than those in the group with the lowest intake. (Whether the
participants changed their preference for whole grains during the follow-up
period is not known.)
The scientists concluded that adults of all
ages should increase the amount of whole grains they eat to three servings a
daythe recommended levelor even more.
Today, most Americans eat less than one daily
serving of a whole-grain food.
For details, contact:
Paul
F. Jacques, (617) 556-3322; ARS
Jean
Mayer USDA Human Nutrition Research Center on Aging at Tufts University,
Boston, Mass.
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Oats
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"HiFi, a superior oat developed by
Agricultural Research Service scientists in Fargo, N.D., and their university
colleagues, boasts bountiful amounts of a healthful, soluble fiber called
beta-glucan (Crop Science, volume 45, page 1664). In fact, HiFi, short
for "High Fiber," provides 50 percent more beta-glucan than whole-oat
products now sold in supermarkets.
Combined with well-balanced meals,
beta-glucan can help lower blood levels of bad (LDL) cholesterol, thus
lessening the risk of heart disease.
Health-label claims now permitted for foods
containing beta-glucan have generated new interest in HiFi, which was first
made available several years ago.
For details, contact:
Douglas
C. Doehlert, (701) 239-1413; USDA-ARS
Red
River Valley Agricultural Research Center, Fargo, N.D.
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Preteen girls with a lower Body Mass Index
reported eating more vegetables.
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Eating veggieslow in calories and an
excellent source of fibermay help preteen girls maintain a healthy
weight. Thats indicated in a study by Childrens Nutrition Research
Center scientists at Houston, Texas, and their colleagues.
Analysis of food records completed by 114
African-American girls aged 8 to 10 showed that those who reported eating more
vegetables had healthier BMI (Body Mass Index) scores (Obesity Research,
volume 12 (Suppl.), pages 53S to 63S).
Preteen African-American girls have
potentially higher-than-normal obesity rates and may be at a greater risk of
heart disease, some cancers, diabetes and stroke when they grow up.
Parents can help their daughters by serving
veggies at meals and keeping a variety of low-calorie veggie snacks handy in
the refrigerator.
For details, contact:
Karen
W. Cullen, (713) 798-6764; USDA-ARS
Childrens
Nutrition Research Center, Houston, Texas.
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Physiologist Mary Kretsch (right) and registered
dietician Monique Derricote demonstrate the Bakan Vigilance Task, which
measures the ability to sustain attention.
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Dieters who have the help of a support group
may experience less stress and less of a brainpower drain than those who go it
alone, research suggests. Scientists with the Agricultural Research
Services Western Human Nutrition Research Center, Davis, Calif., and
their ARS-funded colleagues reported this in Psychoneuroendocrinology
(volume 30, pages 908 to 918).
Fifty-six healthy, overweight women aged 23
to 45 completed the study, participating for eight weeks in either supervised
or unsupervised weight-loss regimens or in a group that neither dieted nor met
as a team.
Dieters who attended weekly support-group
sessions did not have a significant increase in cortisol, a stress-associated
hormone, at the end of the study's first week. Nor did the nondieting
volunteers. But the unaided dieters did.
In addition, at that same checkpoint, the
unassisted dieters scored lower in two computerized tests of their
working-memory capacityone aspect of mental performancethan did the
supervised and the nondieting volunteers.
Even though there were no significant
differences among volunteers' mental performance scores by the four- and
eight-week checkpoints, the differences noted at the end of the first week
nonetheless interest researchers and healthcare professionals who want to help
dieters reduce weight-loss-associated stress and mental performance problems.
Either or both kinds of problemsand the earliness with which they occur
during dietingmay lead dieters to quit their weight-loss programs too
soon.
For details, contact:
Molly
Kretsch, (301) 504-4788; USDA-ARS
National
Program Staff, Beltsville Md.
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Fat itssue from a mouse. The brown borders of the
cells are perlipin protein.
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Two variants of a gene that is already
associated with obesity and type 2 diabetes have now been implicated in storing
excess fat in Caucasian women. The gene contains instructions that the body
uses to form a protein known as perilipin.
At the ARS Jean Mayer USDA Human Nutrition
Research Center on Aging, Tufts University, Boston, Mass., researchers studying
the gene in 361 women volunteers found that those with variants 13041A/G and
14995A/T tended to have a higher percentage of body fat and a bigger waistline
than women with the other two variants (Obesity Research, volume 12,
pages 1758 to 1765).
Researchers now regard these two inherited
variants as significant predictors of obesity in women.
For details, contact:
Jose
M. Ordovas, (617) 556-3102 or
Andrew
Greenberg, (617) 556-3144; ARS
Jean
Mayer Human Nutrition Research Center on Aging at Tufts University, Boston,
Mass.
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Persevering with a weight-loss regimen is
more important than the type of diet selected, when it comes to losing weight.
Thats the conclusion from a study of 160 overweight or obese volunteers
assigned randomly to one of four popular dietsAtkins, Ornish, Weight
Watchers, or Zonefor one year.
Tufts University scientists, funded in part
by the Agricultural Research Service, provide details in a 2005 issue of the
Journal of the American Medical Association (volume 293, pages 43 to
53).
All volunteers who completed the 12-month
regimen achieved a modest but significant weight loss and a 10-percent
improvement in their ratio of good (HDL) to bad (LDL)
cholesterolregardless of diet type.
Only about half of the volunteers following
what the scientists regard as the more extreme diet plansAtkins and
Ornish -- completed the study.
The findings show how important it is for
dieters to choose a weight-loss plan that matches their food preferences,
lifestyle and health.
For details, contact:
Ernst
J. Schaefer, (617) 556-3100; ARS
Jean
Mayer USDA Human Nutrition Research Center on Aging at Tufts University,
Boston, Mass.
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Nutritionist Shanthy Bowman compares total and
saturated fat intakes of overweight and normal-weight adults.
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People who watch more than two hours of
television a day are twice as likely to be overweight than those who do not, an
analysis of the lifestyles and eating habits of more than 8,500 American adults
suggests.
Other habitslittle and bigthat
can contribute to overweight include eating more total fat and saturated fat
than normal-weight folks do, eating chicken without first removing the skin,
skipping breakfast and, of course, not exercising.
Agricultural Research Service scientists at
the Beltsville (Md.) Human Nutrition Research Center found these and other
correlations in their analysis of 1994 to 1996 USDA nutrition-monitoring data,
and reported their findings in a chapter of Body Mass Index: New
Research, (Nova Science Publishers, Inc., pages 117 to 140).
An estimated 64 percent of all American
adults are overweight or obese. And nearly 9 million of our children aged 6
years or older are also obese.
For details, contact:
Shanthy
A. Bowman, (301) 504-0619; USDA-ARS
Beltsville
Human Nutrition Research Center, Beltsville, Md.
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Added sugars can be found in bakery products such
as cakes, cookies and pies.
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Interested in checking the amount of sugars
added to your favorite foods?
Then youll want to take a look at
USDA Database for the Added Sugars Content of Selected Foods, a new,
online source of information about the added sugars, total sugars and
carbohydrates in more than 2,000 common foods.
You can view it on the World Wide Web at:
http://www.ars.usda.gov/Services/docs.htm?docid=12107.
Scientists at the Agricultural Research
Services Beltsville (Md.) Human Nutrition Research Center produced the
online database.
Americans eat about 23 teaspoons of added
sugars every day, totaling 460 calories.
For details, contact:
Joanne
M. Holden, (301) 504-0630; USDA-ARS
Beltsville
Human Nutrition Research Center, Beltsville, Md.
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Glyceollins from soybeans
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Tomorrows soybeans might produce
impressive quantities of glyceollinscompounds that, in laboratory tests,
blocked growth of hormone-dependent human breast cancer cells.
ARS scientists with the Southern Regional
Research Center, New Orleans, La., have shown that soybean seedsand
newly-sprouted soybeanswill produce glyceollins as a defense response to
attack by harmful microbes.
Now the researchers want to coax soybeans do
to that routinely, for large-scale production of the glyceollins.
For details, contact:
Stephen
M. Boué, (662) 915-2019; USDA-ARS Southern Regional Research Center,
c/o USDA-ARS Natural Products Utilization Research Unit, University, Miss.
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Salmonella enterica serovar
Enteritidis
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Salmonella lurking in ready-to-eat
meats can be readily detected with a new, still-preliminary test developed by
Agricultural Research Service scientists based in Beltsville, Md. The assay
relies on PCR (polymerase chain reaction) technology to detect the
food-contaminating microbe.
The test can detect Salmonella even at
very low levels, and it's less expensive than a commercial rapid-detection test
currently in use. Both tests can be performed within an 8-hour incubation
period, or one work shift, meaning that contamination could be detected before
a product such as bologna, turkey or ham slices, or a mixed salad, is shipped.
In turn, that could reduce product recalls.
For details, contact:
Jitu
Patel, (301) 504-7003; USDA-ARS
Henry
A. Wallace Beltsville Agricultural Research Center, Beltsville,
Md.
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The U.S. Department of Agriculture (USDA)
prohibits discrimination in all its programs and activities on the basis of
race, color, national origin, age, disability, and where applicable, sex,
marital status, familial status, parental status, religion, sexual orientation,
genetic information, political beliefs, reprisal, or because all or part of an
individual's income is derived from any public assistance program. (Not all
prohibited bases apply to all programs.) Persons with disabilities who require
alternative means for communication of program information (Braille, large
print, audiotape, etc.) should contact USDA's TARGET Center at (202) 720-2600
(voice and TDD). To file a complaint of discrimination, write to USDA,
Director, Office of Civil Rights, 1400 Independence Avenue, S.W., Washington,
D.C. 20250-9410, or call (800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA
is an equal opportunity provider and employer.
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