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America's Most Wanted
by Brian Amherst
January 6, 2000
The United States eats well, a little too well, according
to experts. Amply supplied with a large supply of
high-calorie food, our diets might seem to be chock full of
every conceivable nutrient. Well, to the question "Getting
all the right vitamins, minerals and other nutrients?" the
most appropriate answer seems to be "Not exactly." Eating a
lot doesn't equal eating a lot of the most important
vitamins and minerals. So, which vitamins and minerals are
likely to show up in short supply in the typical American
diet? Calcium certainly sits at the top of list. According
to the most recent Continuing Survey of Food Intake by
Individuals, which is conducted by the United States
Department of Agriculture (USDA), women and girls age 12 and
up are not consuming adequate calcium from their diet.
Research reveals that about 1200 mg. day suffices for those
over age 50 and 1000 mg a day should be adequate if you're
between the ages of 19 and 50. Since strong bones are formed
during "the first three decades of life," says Laura
Bachrach, MD, of Since strong bones are formed during "the
first three decades of life," says Laura Bachrach, MD, of
Stanford University, ". . .osteoporosis is a pediatric
disease." For long-range protection against that
bone-weakening disease, kids should eat calcium-rich,
low-fat dairy products and plenty of leafy greens (broccoli,
cabbage, kale) as well as salmon (with bones), seafood and
soy. But the calcium campaign does not end in early
adulthood. Bone mass begins to deteriorate at about age 30.
Menopausal hormonal changes can exacerbate bone brittleness.
Medical conditions, including cancer, liver disease and
intestinal disorders; prescription drugs; tobacco and
alcohol indulgence; or a decline in activity, especially the
weight-bearing kind, also jeopardize bone strength.
According to the National Osteoporosis Foundation, about one
in every two American women will break a bone after age 50
due to osteoporosis. That translates into about half a
million fractured vertebrae and more than 300,000 shattered
hips. Frequently, those breaks are life-threatening.
Crucial Calcium
The critical role of calcium in many body functions is
perhaps the most extensively clinically documented among
nutrients. Researchers in the Department of Medicine, Oregon
Health Sciences University in Portland, reviewed
epidemiological and clinical studies conducted over the past
two years on the relationship between dietary calcium and
blood pressure (J Am Coll Nutr October 1999: 398S-405S).
"Nearly 20 years of investigation in this area has
culminated in remarkable and compelling agreement in the
data," the researchers report, "confirming the need for and
benefit of regular consumption of the recommended daily
levels of dietary calcium." Investigators at the State
University of New York, Buffalo School of Dental Medicine,
presented results of their studies of calcium and vitamin C
and gum disease at the June 26, 1998 meeting of the
International Association for Dental Research. Two separate
inquiries revealed that people who consumed too little
calcium as young adults, and those with low levels of
vitamin C in their diets, appear to have nearly twice the
risk of developing periodontal disease later in life than
folks with higher dietary levels of either nutrient.
Calcium:
Much Documented
Researchers offer extensive evidence of calcium's benefits
on many fronts:
n Osteoporosis poses a threat to older men as well as women,
according to Randi L. Wolf, PhD, research associate at the
University of Pittsburgh Graduate School of Public Health.
Dr. Wolf presented her award-winning study to an October 3,
1999 meeting of the American Society for Bone and Mineral
Research. Dr. Wolf suggests that men increase their
consumption of calcium, particularly after age 80, to avoid
age-related declines in the amount of calcium absorbed.
According to Dr. Wolf, "It appears that the hormonal form of
vitamin D, which is the main regulator of intestinal calcium
absorption, may have an important role. We are conducting
more research to better understand the reasons for why
calcium absorption declines with age in men." n Scientists
at Tufts University in Boston did some earlier work on the
calcium-vitamin D connection and reported it in the
September 4, 1997 New England Journal of Medicine. Using the
National Academy of Sciences (NAS) increased recommended
daily intake of 1200 milligrams of calcium and 400 to 600
international units of vitamin D for people over 50, the
Tufts researchers found that with supplementation of the
nutrients, men and women 65 and older lost significantly
less body bone and, in some cases, gained bone mineral
density. n Two studies published in American Heart
Association journals show that atherosclerosis and
osteoporosis may be linked by a common problem in the way
the body uses calcium. The September 1997 Stroke revealed
that, in a group of 30 postmenopausal women 67 to 85 years
old, bone mineral density declined as atherosclerotic plaque
increased. Researchers reporting in Circulation (September
15, 1997) advanced the theory that the
osteoporosis-atherosclerosis connection may be related to a
problem in handling calcium. n For people who had colon
polyps removed, taking calcium supplements decreased the
number of new polyps by 24% and cut the risk of recurrence
by 19%, according to researchers at the University of North
Carolina, Chapel Hill, School of Medicine. The study,
published in the January 14, 1999 New England Journal of
Medicine, was a first in crediting calcium with anti-cancer
properties.
The D Factor
Without adequate vitamin D, your absorption of calcium slips
and bone loss can accelerate, increasing the risk for
fractures. Fifty percent of women with osteoporosis
hospitalized for hip fractures at Brigham and Women's
Hospital in Boston had a previously undetected vitamin D
deficiency (Journal of the American Medical Association,
April 28, 1999). University of Pittsburgh Cancer Institute
researchers told participants at the April 14, 1997 meeting
of the American Association for Cancer Research that vitamin
D "significantly inhibits highly metastatic, or widespread,
prostate cancer in animals," suggesting its potential for
treating men with similar conditions. Few foods that
Americans eat, except dairy, contain much vitamin D, but we
can usually synthesize sufficient amounts from as few as
five minutes' exposure to the sun. But as skin ages, its
ability to act as a vitamin D factory decreases. According
to Michael F. Holick, the director of the Vitamin D, Skin
and Bone Research Laboratory at Boston University Medical
Center, upwards of 40% of the adult population over age 50
that he sees in his clinic are deficient in vitamin D.
Recently, the National Academy of Sciences (the official
body that decrees the required amounts of necessary
nutrients) increased the daily recommendations of vitamin D
to 600 IU for people over 71, 400 IU for those aged 51 to 70
and 200 IU for people under 50. The best dietary sources,
apart from dependable supplements, are dairy and fatty fish
like salmon. Four ounces of salmon provide about 300 IU.
The Facts About Fats
The American lust for low-fat, high-carbohydrate diets
filled with sugary foods has exploded into nothing short of
"obsession," according to experts at the General Research
Center at Stanford University Medical Center (Am J Clin Nutr
70, 1999: 512S-5S). That mania oftens robs us of the crucial
balance of omega-3 and omega-6 fatty acids typical of the
Mediterranean diet that protect us from heart disease by
controlling cholesterol and making blood less likely to form
clots. These fatty acids cannot be made by the body but are
critical for health: n Omega-3 fatty acid (linolenic acid)
comes from fresh, deepwater fish (salmon, mackerel,
sardines) and vegetable oils such as canola, flaxseed and
walnut. n Omega-6 fatty acid (linoleic acid) found primarily
in raw nuts, seeds and legumes and in saturated vegetable
oils such as borage, grape seed, primrose, sesame and
soybean. The American Heart Association recommends limiting
total fat consumption to 30% of daily calories. Saturated
fats like those in dairy and meat products as well as
vegetable oil should comprise 10% of total calories; total
unsaturated fat (fish oils, soybean, safflower nuts and nut
oils) should be restricted to 20 to 22% of daily calories.
Be Sure About B12
Vitamin B12 presents a particular problem for the elderly
because older digestive systems often don't secrete enough
stomach acid to liberate this nutrient from food. (The
elderly have no problem absorbing B12 from supplements,
because it's not bound to food.) Vitamins generally moderate
the aging process but, ironically, that process and the
diseases that frequently accompany it affect vitamin
metabolism (Schweiz Rundsch Med Prax 83, 1994: 262-6). And
because of those changes, we need more of certain vitamins.
This is the case for vitamins D, B6, riboflavin and B12.
Crucial for health, B12 is necessary to prevent anemia, and,
according to recent studies, needed (along with folate and
B6) to help stave off heart disease. B12, with thiamine and
niacin, boosts cognition (Adv Nutr Res 7, 1985: 71-100).
Screening for vitamin B12 deficiency and thyroid disease is
cheap and easy and can prevent conditions such as dementia,
depression or irreversible tissue damage (Lakartidningen 94,
1997: 4329-32). In the January 5-12, 1999 issue of
Circulation: Journal of the American Heart Association, the
AHA urged doctors to screen levels of homocysteine (the
amino acid byproduct of protein digestion that damages
arteries, causes heart disease and, possibly, strokes) in
patients at high risk for heart disease. They also
recommended all Americans to up their daily levels of
vitamins B6 and B12, as well as folic acid. Since fruits,
vegetables or grains lack B12, vegetarians need B12
supplements. And they're a good idea for the rest of us,
too.
Folic Acid Benefits
Folic acid made headlines in the early 1990s when the U.S.
Public Health Service declared that "to reduce the frequency
of neural tube defects [spina bifida, or open spine, and
anencephaly, a lethal defect of the brain and skull] and
their resulting disability, all women of childbearing age in
the United States who are capable of becoming pregnant
should consume .4 milligrams (400 micrograms) of folic acid
per day." This recommendation followed voluminous research
that showed taking folic acid was associated with a
significantly reduced risk of birth defects. (The advisory
is based on the fact that nearly half of all pregnancies are
unplanned. If you think you are pregnant, consult your
health practitioner for supplementary advice.)
A Team Player
Folic acid's efficacy intensifies when it works with other
nutrients. Among many studies on the preventive powers of
folic acid on birth defects, one published in The New
England Journal of Medicine (327, Dec. 24, 1992:
1,832-1,835), disclosed an even greater decrease in neural
tube defects when supplements of folic acid contained
copper, manganese, zinc and vitamin C. As a warrior against
homocysteine, folic acid joins the battalion of B12 and B6
in detoxifying this harmful protein. At the University of
Washington's Northwest Prevention Effectiveness Center,
researchers recently analyzed 38 published studies of the
relationship between folic acid, homocysteine and
cardiovascular disease and, according to associate professor
Shirley A. Beresford, MD, folic acid and vitamin B12 and B6
deficiencies can lead to a buildup of homocysteine.
Compelling Evidence
Canadian researchers reported in the Journal of the American
Medical Association (275, 1996: 1893-1896) that men and
women with low folic acid have a 69% increase in the risk of
fatal coronary heart disease. This 15-year study of more
than 5,000 people stressed the need for dietary
supplementation of folic acid. Folic acid also has been
credited with the potential to protect against cancers of
the lungs, colon and cervix. It appears to help reverse
cervical dysplasia, the precursor cells to cervical cancer,
especially for women taking oral contraceptives, which may
cause a localized deficiency of folic acid in the cells of
the cervix. According to Shari Lieberman, PhD, and Nancy
Bruning, authors of The Real Vitamin & Mineral Book (Avery),
folic acid derivatives work with neurotransmitters, the
chemicals that permit signals to be sent from nerve fiber to
nerve fiber. A lack of folic acid can cause some
nervous-system disorders, such as depression, schizophrenia
and dementia; it also may be related to some forms of mental
retardation. Other supporting roles of folic acid, according
to researchers: the formation of normal red blood cells,
important for preventing the type of anemia characterized by
oversized red blood cells; strengthening and improving white
blood cell action against disease; limiting production of
uric acid, the cause of gout.
The Best Sources
Many foods are rich in folic acid: beef, lamb, pork and
chicken liver, spinach, kale and beet greens, asparagus,
broccoli, whole wheat and brewer's yeast. But experts
believe that only 25 to 50% of the folic acid in food is
bioavailable. Processing also reduces an estimated 50 to 90%
of its content. Folic acid supplementation overcomes these
obstacles with little risk, as it has no known toxicity.
Women taking folic acid who are current or former users of
oral contraceptives may require additional zinc. And be sure
to augment your folic acid supplement with its synergistic
counterpart, vitamin B12.
Focus on Fiber
The American Heart Association came out squarely behind
fiber in a June 16, 1997 issue of its journal Circulation:
Double your daily intake to lower cholesterol and the risk
of heart disease. The American diet is consistently low in
fiber, notes Linda Van Horn, PhD, RD, author of the article.
Twenty-five to 30 grams a day from foods (or supplements)
are not only heart healthy but seem to aid weight control.
Iron Problem
Getting enough iron? An estimated 25% of adolescent girls in
the United States are iron deficient, according to an
October 12, 1996 issue of the British medical journal The
Lancet, which reported that girls who took iron supplements
performed significantly better on verbal tests than those
who took a placebo. "Teenage girls should be regularly
tested for iron deficiency because rapid growth and the
onset of menstruation during puberty increase the body's
need for iron," says Ann Bruner, MD, of the Johns Hopkins
Children's Center and a lead author of the study.USDA data
reveal that women up to age 50 also tend to get much less
than recommended levels of iron, a lack of which leads to
anemia, a deficiency of red blood cells, hemoglobin or
volume of blood. For kids, deficiency is more common from
six months to four years and during the rapid growth spurts
of adolescence when the body is growing so quickly that the
body's iron stores may sink to dangerous levels. Vegetarian
women run the greatest risk for deficiency, as meat is
iron-rich; foods like beans, grains and vegetables also
contain some iron. Supplements, of course, supply easily
absorbable iron. And to absorb iron from vegetarian sources,
take vitamin C with your meals. That boosts the amount of
this mineral you will take in. Bear in mind, however, that
certain folks-older men and post-menopausal women-generally
have adequate dietary supplies of iron. Of greater concern,
in fact, is excessive iron, and for these folks iron-free
multivitamin and mineral supplements are available.
Ante Up the Antioxidants
Antioxidant nutrients help protect the body from
oxygen-scavenging molecules called free radicals. The
products of pollution, the body's own metabolic processes
and other sources, free radicals are linked to heart
disease, cancer and other chronic health problems. The most
important antioxidants, which include vitamin C, E, beta
carotene, and selenium, are often lacking in the American
diet. Plus, optimal amounts of vitamin E cannot be consumed
from food. You need supplements. The bottom line: even
though we live in a land of plenty, you can still miss vital
nutrients. So make sure to consume these vital substances.
Sprouts: Nutritional
Source of Missing Nutrients
In the search for the nutrients missing from America's diet,
one big help is the sprout. The sprout is truly one of
nature's heavyweights: fresh, tiny and moist, its power
punch of vitamins, minerals, protein, chlorophyll and
disease-busting phytochemicals land it in a weight class far
beyond that of its full-grown competitors. Size does NOT
matter to this nutritional giant. A championship belt
currently wraps around the miniscule broccoli sprout,
catapulted into the ring by Paul Talalay, MD, professor of
pharmacology and molecular sciences at Johns Hopkins
University. Dr. Talalay discovered that the seedlings
contain substantially more of the cancer-fighting substance
sulforaphane than mature plants (Proc. Natnl. Acad. Sci.
USA, 94, 10367-10372). Sprouts, the quintessential health
food of the Sixties, provide a wonderfully varied and
versatile way to get your daily greens. Raw or cooked,
strong or mild, vegetable and grass sprouts and their algae
cousins add low-calorie texture to recipes and a rich,
diverse complement of nutrients and fiber.
Ancient Asia to the Modern Lab
Asians stir-fried sprouts as one of the earliest fast foods
as long as 5,000 years ago. The ancient Chinese relied on
sprouts for year-round vegetables in colder regions of their
vast country. Today, researchers studying sprouts and adult
plants have identified their important chemoprotective and
other health-bolstering substances. In Paul Talalay's
research project at Johns Hopkins, scientists found that
three-day-old broccoli sprouts contain up to 50 times more
sulforaphane than mature plants, which prompts the body to
produce an enzyme that prevents cancer tumors from forming.
Uniform levels of the compound saturate the shoots, unlike
the chemically uneven adult plants. The Brassica family of
broccoli and cabbage is richly endowed with phytochemicals
that also help reduce estrogen levels associated with breast
cancer. Other phytochemical compounds in the Brassica family
are associated with the prevention of stomach and lung
cancers. Most of the initial landmark work on phytochemicals'
cancer-fighting powers has taken place since 1989 under the
aegis of the National Cancer Institute's "Designer Food
Program," which isolated, for example, the isoflavones in
beans that seem to neutralize cancer-gene enzymes.
Strong Suit: Soy and Spirulina
The isoflavones and phytosterols in soy produce an
estrogenic effect that appears to relieve menopausal
symptoms and help prevent breast cancer. Soy foods expert
Mark Messina, PhD, has done extensive work on the subject,
some of which has been published in the Journal of the
National Cancer Institute 83, 1991: 541-6. Researchers also
have synthesized a bone-strengthening form of soy
isoflavones called ipriflavone, following impressive
clinical trials in the treatment of osteoporosis (American
Journal of Medicine, 95 [Suppl. 5A] (1993): 69S-74S).
Spirulina and other micro-algae are fascinating organisms
that inhabit a niche between the plant and animals kingdoms.
Named for its tiny spirals, spirulina, a blue-green algae,
grows in saline lakes but is cultured for maximum
nutritional content. In her book Whole Foods Companion
(Chelsea Green), Dianne Onstad notes that spirulina contains
"the highest sources of protein, beta carotene and nucleic
acids of any animal or plant food." Its nucleic acids, she
says, benefit cellular regeneration; its fatty acids,
especially GLA and omega-3 acids, make it one of the most
complete foods. Sprouts, like any other produce, should be
rinsed thoroughly before serving. People at high risk for
bacterial illness-young children, the very elderly or folks
with weakened immune systems-should limit their consumption
of raw sprouts. But no matter how you eat them, you may find
more spring in your step from these tiny, sprouting
nutritional wonders.
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