The 1995 Dietary Guidelines for Americans will stress the enjoyment of
foods--a wide variety of them--rather than convey the impression of many foods
as "bad" for health, according to the 52-page report of the Dietary
Guidelines Advisory Committee. It was submitted this summer to the Secretaries
of Agriculture and Health and Human Services. After reviewing the committee's
recommendations, the departments will finalize the text for the 1995 revision
and issue a consumer brochure late this year or early next year.
The committee suggested "language that is deliberately positive and
intended to convey a message of enjoyment of foods as an underlying
principle," the report states. "The Dietary Guidelines apply to diets
consumed over several days, and not to single meals or foods," said
committee chair Doris Calloway of the University of California, Berkeley. The
guidelines are aimed at Americans age two and above and are not intended for
infants and toddlers under two years.
The committee recommended leaving the first guideline, "Eat a variety
of foods," unchanged from the 1990 edition. They suggested adding an
explanation of variety in relation to vegetarian diets for the first time and
distinguished between enriched and fortified foods.
Recognizing the growing obesity problem in this country and the many health
risks it imposes, the committee expanded the second guideline to recommend that
Americans "balance food intake with physical activity" to prevent
weight gain--which is now the primary target. It also recommends that people
"maintain or improve your weight" as a major goal.
"The committee felt that maintaining weight is a more reasonable goal
than losing weight. The ability to lose weight and keep it off has been
disappointing to most people," said Calloway, noting that people with risk
factors for chronic diseases still may need to lose. The report admonition that
"most adults should not gain weight" is a shift from the
long-accepted view that people naturally gain weight during middle age.
The committee also placed more emphasis on plant foods in healthful diets,
moving the guideline ahead of the advice to choose a diet low in fat, saturated
fat and cholesterol. That was done for consistency with the Food Guide Pyramid,
in which grains, fruits and vegetables form the base. While the recommendations
on fat do not apply to infants and toddlers to age two, the report notes that
"children should adopt a diet that, by about five years of age, contains
no more than 30 percent of calories from fat."
Because sugar, salt and sodium are contained in prepared and processed
foods, the committee changed guidelines five and six from using these
"only in moderation" to "choosing a diet moderate" in
sugars, salts and sodium. They advise Americans to use the new Nutrition Facts
Label, available on all processed foods and many other foods, to estimate their
intake of fat, cholesterol and salt/sodium.
The seventh guideline, recommending that those who drink alcohol beverages
do so in moderation, was left unchanged. But the report added that it's best to
take alcohol with meals. Noting that alcohol is calorie dense, the report
includes the calorie value of beer, wine and distilled spirits.
For more information on the report, contact Debra Reed, executive
committee secretary from USDA, Agricultural Research Service, (202)
720-3804.
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Low-fat ice cream with that old-fashioned taste and texture is one of many
foods that may be developed using a new fat substitute called Fantesk. A blend
of starch, tiny droplets of oil and water, this versatile product also may find
its way into low-fat meat products, margarines and coatings that hold buttery
flavor for diet popcorn. Fantesk also promises a variety of nonfood uses.
ARS scientists found that a starch-oil combo formed a thick gel when
processed in superheated steam under pressure. And it did not separate after
cooling. Further, the gel did not separate after freezing, thawing and even
melting in a microwave, making it an ideal food ingredient. The presence of
vegetable or animal fats makes Fantesk act as an emulsifying or dispersing
agent, letting it mix with materials, such as some pharmaceuticals, that don't
themselves mix well with water.
Usually 15 to 30 percent vegetable oil, Fantesk can be dried and milled
into an easily flowable powder that can later be redispersed in water to make
soft gels. This saves the cost of transporting a water-laden product. The
researchers made a film of Fantesk containing limonene, the volatile oil from
citrus rinds, and another film incorporating fresh strawberries. Such films
release aromas and flavors when chewed. Opta Foods of Bedford, MA, has applied
for an exclusive license for food applications of Fantesk.
For more information, contact Kenneth Eskins, (309) 681-6566 or George F.
Fanta, (309) 681-6356, National Center for Agricultural Utilization Research,
Peoria, IL.
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People don't need to become severely deficient in magnesium for the brain
to become hyperactive. A new study confirms earlier reports that a marginal
magnesium intake overexcites the brain's neurons and results in less
coherence--creating cacaphony rather than symphony--according to
electroencephalogram (EEG) measurements. During half of the six-month study, 13
women consumed 115 milligrams of magnesium daily--or about 40 percent of the
Recommended Dietary Allowance (RDA). During the other half, they got 315 mg
daily--a little more than the 280 mg recommended for women. After only six
weeks on the marginal intake, EEG readings showed significant differences in
brain function.
Magnesium is the fourth most abundant element in the brain and is essential
in regulating central nervous system excitability. Clinical studies of people
severely deficient in this essential element have reported epilepsy-type
convulsions, dizziness and muscle tremors or twitching as well as many
psychological symptoms, including irritability, anxiety, confusion, depression,
apathy, loss of appetite and insomnia. While the marginal intake in this study
did not produce such severe symptoms, it did hype brain activity.
This is the first experimental study in which magnesium intakes were
tightly controlled and EEG measurements were analyzed by computer so they could
be statistically compared. Good sources of magnesium include whole grains,
nuts, peanut butter, cottonseed, peanut and soybean flours, green leafy
vegetables and spices. It's better to get magnesium from foods rather than
supplements because high doses have a laxative effect--the body's way of
preventing toxic levels.
For more information, contact James G. Penland, (701) 795-8471, Grand
Forks Human Nutrition Research Center, Grand Forks, ND.
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A machine that removes fats, chemical residues and other compounds from
food products using harmless carbon dioxide will be commercialized by Applied
Separations of Allentown, PA. The machine is a multipurpose Supercritical Fluid
Extractor (SFE), developed jointly with ARS scientists. Besides removing fats,
it could be used to extract residues of herbicides and pesticides from grains
and meats, and to remove trace antibiotics, nitrosamines and hormones from
meat. To extract materials, it uses carbon dioxide instead of toxic organic
solvents. The U.S Environmental Protection Agency has mandated that use of
these organic solvents be reduced or eliminated because of their harmful
environmental effects. Applied Separations will also do pilot tests of SFE for
industrial uses.
For information from ARS, contact Robert J. Maxwell, (215) 233-6433, Food
Safety Research Unit, Philadelphia, PA.
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Vitamin E, vitamin A and two other antioxidants--lutein and
zeaxanthin--have been found in the eyes' lenses, suggesting they may help
protect against the formation of cataracts. Analyzing both healthy and
cataract-clouded human lenses removed during surgery, researchers found
significant levels of vitamins E and A, lutein and zeaxanthin. These latter two
compounds are carotenoids--plant pigments related to beta carotene--and are
abundant in yellow and dark green leafy vegetables, such as spinach, broccoli
and kale. No other carotenoids, including beta carotene and lycopene--two major
carotenoids in human blood--were found in the lenses. Population studies have
shown a relationship between carotenoid or vitamin A levels in the blood and a
lower incidence of cataracts.
Of the 31 lenses analyzed, those removed from Asian Indians, who
traditionally eat a lot of vegetables, had significantly higher levels of the
antioxidants than those from Americans. Among the American lenses, antioxidant
levels differed significantly, possibly reflecting a wide difference in
vegetable intake among Americans.
For more information, contact Kyung-Jin Yeum, (617) 556-3128, Jean Mayer
USDA Human Nutrition Research Center on Aging at Tufts Boston, MA.
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A daily dose of the blue-green algae Spirulina may help prevent cancer of
the mouth, a study shows. The finding could benefit people in developing
countries where the algae is cheaper than vitamins. After one year of consuming
only one gram of the algae daily, 45 percent of the volunteers had complete
regression of the thick, white, pre-cancerous patches in the mouth known as
leukoplakia. Adding in those volunteers who showed significant improvement
raised the figure to 57 percent who benefitted from Spirulina. That compared to
seven percent of those who got a placebo.
The study--the first human evaluation of the cancer-preventive potential of
Spirulina--was coordinated by an ARS researcher and conducted in southwestern
India where the incidence of leukoplakia is high. The researchers tested
Spirulina because it is an inexpensive source of beta carotene and related
carotenoids in many developing countries. In other research, the algae has
inhibited oral cancer in animal studies, while beta carotene or vitamin A
supplements have reversed pre-cancerous conditions in people's mouths. Cancer
of the mouth and of the cervix--which has the same kind of mucus membrane--is
on the rise worldwide.
For more information, contact Padmanabhan P. Nair, (301) 504- 8145,
Beltsville Human Nutrition Research Center, Beltsville, MD.
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Major dairy manufacturers have contracted to supply 1.3 million pounds of
ARS-developed, low-fat, mozzarella cheese for USDA's national school lunch
program. Containing 50 percent less fat than standard mozzarella, the new
low-fat cheese melts and tastes just like the regular kind that usually tops
pizza. In trials in public schools throughout the country, most students
couldn't tell the difference between the low-fat and the full-fat cheese.
For more information, contact Edyth L. Malin, (2115) 233-6444, Dairy
Products Research Unit, Philadelphia, PA.
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A cayenne pepper that sent an ARS laboratory into overdrive to fill 28,000
requests for seed has sped to the market in two years. Charleston Hot, released
in early 1993, made its dinner table debut this year in two new hot
sauces--Holy City Heat, made by Atlantis Coastal Foods, in Charleston, SC, and
Charleston Hell Hot Sauce, made by Three Amigos restaurants. Also, at least
nine outlets are selling Charleston Hot seed: DeGiorgi Seed Company, Omaha, NE;
Jones Deade, Charleston; Pepper Joe's, Inc., Norristown, PA; Pepper Gal, Ft.
Lauderdale, FL; R.H. Shumways, Graniteville, SC; R.H. Shumway's Totally
Tomatoes, Augusta, GA; Rupp Seeds, Wauseon, OH; South Carolina Foundation Seed
Association, Clemson, SC; and Nanjemoy Flower and Herb Farm in Nanjemoy, MD.
For more information, contact Philip D. Dukes or Richard L. Fery, (803)
556-0840, U.S. Vegetable Laboratory, Charleston, SC.
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When clinicians measure blood levels of the amino acid homocysteine only
after an overnight fast, they could miss nearly half of the people with
elevated levels. And high homocysteine levels have been linked to increased
risk of heart disease and stroke. A second measurement--taken after a dose of
another amino acid, methionine, commonly gotten from foods--is needed to
identify all cases, according to study of 247 volunteers. That's because some
people have a low tolerance for methionine and convert it rapidly to
homocysteine, which raises blood levels. High blood levels of homocysteine may
be damaging to arteries. Both tests are needed because three vitamins are
involved in homocysteine metabolism. The overnight fast test reveals those
people with folate (folic acid) or vitamin B12 deficiency, while the methionine
test detects people who lack vitamin B6.
Also, the researchers streamlined the second test so homocysteine can be
measured two hours after a dose of methionine instead of four or six hours.
For more information, contact Andrew G. Bostom or Jacob Selhub, (617)
556-3356/-3191, Jean Mayer USDA Human Nutrition Research Center on Aging at
Tufts, Boston, MA.
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One in three girls and one in four boys had body fat levels considered
obese for adults, according to a study of more than 600 children and teens
living in the Houston area. That's a big jump from 20 years ago when only one
in six girls and boys exceeded the obesity threshold for adults--32 percent fat
for women and 25 percent fat for men.
The study, which is still ongoing, also found differences among white,
black and Hispanic youths. Hispanic youths had the highest average body fat--32
percent for girls and 24 percent for boys. White girls had the lowest average
body fat--26 percent-- among the females. And black boys averaged the
lowest--19 percent--among the males. All subjects were measured by two highly
accurate methods for assessing body composition: dual energy x-ray
absorptiometry (DEXA) and emissions of potassium-40, a radioactive form of the
element occurring naturally in the body in tiny amounts.
This is the only study worldwide to assess fat and lean composition of
children in different ethnic and racial groups. When complete, it should
produce data on 1,000 children--enough for developing charts that show normal
ranges of body composition similar to the height and weight growth charts in
pediatricians' offices.
Another finding in this study of more than 600 youths is that black
children start their growth spurt two to five years earlier than white or
Hispanic children. This points to the need to customize dietary recommendations
for different ethnic groups to provide the protein and minerals children need
when they need them.
Black girls and boys tend to grow taller and heavier and mature faster than
white or Hispanic children. At age 6, black girls begin adding significantly
more muscle and bone than white or Hispanic girls, while these two groups wait
till around age eight or nine for their growth spurt. Black boys begin to
outpace white and Hispanic boys at age seven and grow even faster at age 12,
when white and Hispanic boys are beginning their growth spurts.
Current data on changes in body composition--fat, muscle and bone--during
childhood were developed from data gathered in the 1950's, 60's and 70's on
white children only. And they only give an average value for different ages.
This ongoing study of boys and girls ages three to 18 aims to develop body
composition charts showing the range of normal growth patterns among the major
ethnic groups in this country. It shows that today's youths are bigger and
taller than those of three to four decades ago along with having more body fat.
For more information, contact Kenneth J. Ellis, (713) 798-7132,
Children's Nutrition Research Center, Houston, TX.
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Black adolescent girls had lower aerobic capacity than their white
counterparts during a treadmill test, even though both ethnic groups had the
same amount of body fat. Researchers conducted the study of 93 girls, ages 11
to 16, because information on the physical fitness of U.S. adolescents of
different ethnic origins is scanty. So they measured peak oxygen
consumption--an indicator of fitness known as VO2max--in 40 black girls and 53
white girls while they ran on a treadmill to the point of exhaustion.
The black girls consumed 17 percent less oxygen than the white girls during
he test and reached exhaustion nearly a minute earlier--8.5 vs 9.4 minutes.
Blood tests showed that hemoglobin- -the oxygen-carrying molecule in red blood
cells--was six percent lower in the black girls. Studies done in other
countries suggest that ethnicity contributes to differences in aerobic fitness.
Researcher don't yet have an explanation but suspect both genetics and
lifestyle contribute to the differences. They are currently analyzing data they
collected on the girls' body composition and resting metabolic rate for clues.
For more information, contact William W. Wong, (713) 798-7168, Children's
Nutrition Research Center, Houston, TX, or James M. Pivarnik, (517) 353-3520,
now at Michigan State University, East Lansing, MI.
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A daily boron supplement did not relieve hot flashes and night sweats in a
majority of women going through menopause, contrary to some reports by women
who take extra boron. Half of the 46 women in a controlled, five-week study
reported more frequent and severe hot flashes and night sweats, which
interrupted sleep, and more total menopausal symptoms while taking a
2.5-milligram boron supplement than when they got a placebo. Only 15 percent of
the women reported beneficial, while 35 percent reported no difference.
Boron supplements are being recommended by some pharmacies and health food
stores based on reports from women who have gotten relief. According to this
small study, however, extra boron may exacerbate menopausal symptoms or have no
effect more often than it counteracts them.
For more information, contact James G. Penland, (701) 795-8471, Grand
Forks Human Nutrition Research Center, Grand Forks, ND.
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