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March 2000 Newsletter
The Incredible Benefits of Soy
Providing a rich source of protein and nutrients, soy contains plentiful
amounts of unique therapeutic compounds and phytochemicals. Phytochemicals
are the nutritional substances found in many plants. Because of their
tremendous potential for clinical application, soy and its phytochemical
constituents are being investigated by several major health organizations.
Saponins are complex glycosidic compounds present in a diverse array
of plants. Soybeans are one of the major sources of glycosidic compounds
found in the human food supply. A detergent-like action has been attributed
to saponins that arises from the water-soluble carbohydrate molecules
being mixed with the fat-soluble sapogenic portion. Characteristically,
saponins have been associated with cholesterol reduction. Saponins have
also been shown to provide antioxidant and cell-protective properties.
Other research points to the antibiotic and potential anticancer benefits
that saponins may yield.
Soy contains a broad range of isoflavones, but research has centered
predominantly on two: genistein and diadzein. Isoflavones are among
the most investigated ingredients of soy. A key reason for this appears
to be their ability to offer protection against various male and female
hormone-related cancers, including those affecting the prostate and
breast. Because they resemble and act like estrogens in the body, isoflavones
have the ability to compete and interfere with the body's natural estrogens.
Studies indicate that isoflavones either administered or present in
the diet may be protective against high levels of synthetic estrogens.
Genistein, the predominant soy isoflavone, has been shown to provide
specific anti-tumor, cell growth-regulatory benefits. In a study of
pre-menopausal women it was found that a daily intake of 60 grams of
soy protein containing 45 mg of isoflavones had various hormone regulatory
effects.
Whether used as a primary dietary protein source or as part of a nutritional
supplementation program, the benefits of soy cannot be overlooked.
References: Milgate, J., Robert, D.C.K. Nutritional and biological
significance of saponins. Nutr Res 15(8):1223-49, 1995. Setchell, K.
The role of soy products in reducing risk of cancer. J Nat Cancer Inst
83:8, 1991.
Ginseng: More Than Energy
There are three types of ginseng commonly found in the US market and
they are identified by the use of the word "Panax": Panax ginseng, Panax
quinquefolius, and Panax notoginseng. The species Panax ginseng often
is called Oriental ginseng, Chinese ginseng, Korean ginseng or Panax ginseng.
The species Panax quinquefolius is American ginseng, which is the common
name recommended by the American Herbal Products Association (AHPA).
An important distinction that marks true ginseng is the presence of ginsenosides.
The particular composition of ginsenosides affects the actions to be expected
from a given herb-the higher the quantity of ginsenosides, the better
the quality of the ginseng.
In addition to identifying the properties of a true ginseng, it is important
to distinguish between a "red ginseng" and a "white ginseng." Red and
white ginseng are not plant species, but rather are terms used to describe
the processing that the root has undergone. All ginseng roots, when picked
and dried, are white. Processing the root with steam is what makes it
red. In addition to changing its color and preserving it, the process
makes the ginseng more "warm." Consequently, red Oriental ginseng is more
stimulating than white Oriental ginseng. The recommended dosage for Oriental
ginseng ranges from 2 to 8 grams daily and should be taken according to
a schedule of two to three weeks on and two weeks off.
Although not many studies have been conducted on American ginseng, recommended
dosage is 2 to 9 grams daily. Large amounts can cause over-stimulation,
which may result in increased blood pressure, diarrhea, skin eruptions,
and insomnia.
The Journal of Sports Science reported that ginseng may exhibit estrogen-like
effects on estrogen receptor-positive breast cancer cells and may play
a protective role against breast cancer.
Korean red ginseng showed a therapeutic effect on erectile dysfunction
on 60% of a total of 90 patients tested, according to a 1995 study.
References: Yun T.K., Choi S.Y. "Preventive Effect of Ginseng Intake
Against Various Human Cancers: A Case-Control Study on 1987 Pairs." Cancer
Epidemiology-Biomarkers and Prevention. 4(4):401-8, 1995. Choi H.I., et
al. "Clinical Efficacy of Korean Red Ginseng for Erectile Dysfunction."
Int J Impot Res 7(3):181-6, 1995.
Olive Leaf Extract: Nature's Antibiotic
Recent studies indicate that the olive tree leaves may contain our best
weapon against a host of disease-producing bacteria. As more bacteria
mutate and resist commonly prescribed antibiotics, scientists are searching
for alternatives.
After 40 years of using antibiotics for many ailments, physicians are
now confronting bacteria that have built defenses against drugs. Some
infectious bacteria that were once treatable are stronger and sometimes
deadly. The reappearance of highly infectious bacteria is caused in part
by the overuse and misuse of antibiotics, but the resilience of bacteria
also stems from the ingenious biochemistry of the microorganisms themselves.
To survive, microorganisms and fungi mutate into resistant strains.
Oleuropein, the bitter glucoside lodged in leaves of the green olive
tree (Olea europaea), contains components that may be valuable for treating
both infectious and degenerative diseases.
In a document describing how oleuropein works, Dr. James R. Privitera,
M.D., of Covina, Calif., reports that olive leaf extract brings about
a critical interference with certain amino acid production processes necessary
for the vitality of a specific virus.
The researchers conclude that olive leaf extract could be taken by people
exposed to any type of pathogenic microorganism, both on a preventive
basis and, if disease symptoms are present, as a medication.
Dosages recommended by health professionals include one or two tablets
or capsules totaling 250-500 mg daily for preventive purposes. For treating
symptoms, the dosage varies with the severity of disease and ranges from
four to eight tablets or capsules daily.
References: Walker, M. Explore! 7(4): 31-7, Sept. 1996. Pooley, R.J.,
& Peterson, L.R. In Shulman, S.T., & Phair, J.P., et al., eds. The Biologic
and Clinical Basis of Infectious Disease, 5th Ed.: 550, 1997.
Choline, Lecithin, and Your Health
Lecithin is a special type of fat called a phospholipid. About 13% by
weight of the lecithin molecule is choline. Most choline in the diet is
derived from lecithin. Some foods contain it in the free form or as a
component of other phospholipids. One tablespoon of lecithin granules
provides about 1,725 mg of phosphatidylcholine and 250 mg choline, a little
less than the content in an egg.
In many of the studies that convinced nutritionists that choline is an
important nutrient, lecithin appears to reduce the risk of cardiovascular
disease several ways: by contributing cholesterol-lowering polyunsaturated
fats, inhibiting intestinal absorption of cholesterol, increasing the
excretion of cholesterol and bile acids, and favorably affecting lipoprotein
profiles.
In one study, people with high blood lipids were given 10.5 grams of
lecithin for 30 days. Their average total cholesterol and triglycerides
decreased by an impressive one-third, LDLs decreased by 38% and HDLs increased
by 46%. The researchers concluded that "lecithin . . . should be administered
for the prevention and treatment of atherosclerosis."
Human studies suggest lecithin and choline may also benefit memory. In
one study, investigators gave healthy adults either 2 tablespoons of lecithin
or a placebo for five weeks. By the end of the study, memory test scores
of the lecithin group improved significantly, exceeding those of the placebo
group.
References: Wojcicki, J., Pawlik, A., et al. "Clinical evaluation
of lecithin as a lipid-lowering agent." Phytotherapy Research, 9:597-79,
1995. Meck, W.H. "Choline and development of brain memory functions across
the life span." Seventh International Congress of Phospholipids, Brussels,
Belgium, September 1996.
Food for Thought
One of the most common indications of deteriorating brain function is
memory loss. Many older people, when they become aware of memory lapses,
jump to the conclusion that they are experiencing the early signs of Alzheimer's
disease, when in fact their declining memory may be rooted in a nutritional
deficiency.
Scientific research clearly showed that healthy brain functioning depends
on sufficient amounts of two B vitamins: Thiamine and Inositol.
B1 (thiamine) helps convert glucose to energy. It also mimics acetylcholine
(a neurotransmitter involved in memory) and plays a role in brain functions
related to memory and cognition. A recent study shows that high-dose thiamine
supplementation (3-8 grams per day) may actually decrease the deleterious
effects of senility.
Thiamine supplementation also appears to elevate mood. In another study,
120 women took either placebo or 50 mg of thiamine daily for two months.
Before-and-after tests assessed mood, memory, and reaction times. Women
who took the thiamine supplements reported feeling significantly more
clearheaded, composed, and energetic.
Inositol occurs in cell membranes as phosphatidylinositol. Two clinical
trials have shown that rather large amounts of inositol can improve certain
psychiatric disorders. In a double-blind, controlled crossover study of
13 patients with obsessive-compulsive disorder conducted by Mendel Fux,
M.D., and colleagues at Ben Gurion University of the Negev in Beersheva,
Israel, 18 grams per day of inositol for six weeks significantly lowered
scores on the Yale- Brown Obsessive Compulsive Scale.
Another study conducted by Joseph Levin, M.D., looked at the effects
of taking inositol for four to six weeks in patients with depression,
panic disorder, schizophrenia, and obsessive-compulsive disorder. Inositol
had a significant therapeutic effect for depression, panic disorder and
obsessive-compulsive disorder illnesses that respond to Prozac.
The sophisticated chemistry of the brain depends on many nutrients, and
further research is needed to uncover the effects of supplementation on
various central nervous system disorders.
References: Benton, D., et al. "Thiamine supplementation for mood
and cognitive functioning." Psycho-pharmacology, 129: 66-71, January 1997.
Fux, M., et al. "Inositol treatment of obsessive-compulsive disorder."
Am J Psychiatry, 153: 1219-21, 1996.
Vitamin E Reduces Prostate Cancer
A recent study suggests that alpha-tocopherol (Vitamin E) may reduce
the risk of advanced prostate cancer. A prospective, placebo-controlled,
double-blind trial carried out by Olli P. Heinonen and his colleagues
at the University of Helsinki in Finland studied 29,133 men aged 50 to
69. The subjects received either 50 IU daily of alpha-tocopherol, 20 mg
daily of beta-carotene, both supplements together, or a placebo. The treatments
were continued for five to eight years.
Compared with the placebo group, the men taking only alpha-tocopherol
developed 36% fewer prostate cancers. The men taking both supplements
had a 16% lower incidence.
Combined, the two groups receiving alpha-tocopherol developed 32% fewer
prostate cancers than the two groups that did not receive it. Their incidence
of advanced cancer was 40% lower, and their mortality from prostate cancer
was 41% lower.
These results suggest that vitamin E may help prevent prostate cancer
from moving from the latent to the progressive stage. There is evidence
that alpha-tocopherol may also reduce benign prostatic enlargement. If
this were so, men who take vitamin E would have fewer symptoms-and would
therefore be less likely to receive tests that might lead to cancer diagnosis.
As such, further clinical trials are suggested to confirm vitamin E
being recommended for prostate cancer prevention.
Reference: Journal of the National Cancer Institute 1998;90(6):4406.
Health Tip
Vitamin C may be working behind the scenes to prevent heart disease say
scientists at the Lipid Research Laboratory at Sheba Hospital in Tel Hashomer,
Israel.
Based on a popular hypothesis that vitamin C helps recycle the vitamin
E that is spent gobbling up free radicals, the Israeli researchers studied
healthy men with no known risk of cardiovascular disease. The men ate
a diet relatively low in vitamin C for one month before being split into
two groups.
For three months, one group continued on the low-C diet, and the second
received fresh-squeezed orange juice to raise their daily vitamin C intake
to 500 mg.
Shifting to a high-C diet raised vitamin C plasma levels nearly fourfold
to a level shown to maximize protection from coronary artery disease.
Because vitamin E levels did not change, the authors concluded that vitamin
C regenerated the vitamin E spent in quenching free radicals.
Reference: American Journal of Clinical Nutrition 1998;67:2405.
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