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Reporting Research Statistics
Nutrition and Brain Function
Antioxidant Brain Protection
Ask Dr. J: Peptic Ulcers
Ask Dr. J: Carotid atherosclerosis
In the Health News
Diet and Disease
Recipe of the Month: Guacamole
and Gazpacho
References
Dear Friends,
If you know how to manipulate statistics, you
can appear to prove or disprove almost anything.
I am particularly interested in recent articles
that appear to show that ginkgo biloba does
not work to help improve memory and that vitamin
E is dangerous.
In similar articles that I have already discussed,
they suggested that vitamin C was either risky
for arteries or a cancer promoter (both untrue),
or that St. John’s wort did not help depression
(but was as good as Prozac relatives!).
There is a fascinating little book by Darrell
Huff, first printed in 1953, called How to Lie
with Statistics. He notes that the death rate
in the Navy during the Spanish American war
was 9 per thousand, while in New York it was
16 per thousand. Navy recruiters used the figures
to show that it was safer to be in the Navy
than in New York.
They neglected to mention that the Navy is
made up of young, fit, carefully selected men,
while the New York population included the elderly,
the infirm, infants, and hospitalized patients,
so the two groups were hardly comparable.
Data manipulation still takes place in medical
science, when a researcher or a reporter wants
to make a point. A study may be too small or
too short to reach significance. Researchers
can then claim that they found no evidence of
effectiveness. Authors may also draw conclusions
that are not justified by their own data.
The recent study on ginkgo biloba is an example
of misleading conclusions. Many studies have
shown that as people age, and memory starts
to fail, they can restore and maintain their
mental function with supplements of ginkgo biloba.
Research supports a daily dose of 120 to 240
mg of standardized extract. In this study, the
subjects had normal memory function, and in
six weeks they had no improvement with 120 mg
daily. One can only conclude from this that
taking ginkgo at a typical dose (but not high
doses) for a short time may not help people
with normal memory.
News reporters may mislead readers with their
headlines and opening paragraphs, even if later
in the article they temper those remarks. Many
readers do not venture deeply into the text.
When the first scientific article showing benefits
from ginkgo appears, that is news. The next
nine are not. Then one appears that shows no
benefit, and that is news again. Tempting material
for reporters. We must draw our conclusions
from the weight of evidence, not one study.
Right now, the evidence shows that ginkgo biloba,
St. John’s wort, vitamin C, vitamin E,
and numerous other dietary supplements and herbs
are safe and effective in the treatment and
prevention of many diseases.
Last month I reported that adequate dietary
linoleic acid (an omega-6 polyunsaturated fatty
acid, or PUFA), is an essential fatty acid (EFA),
found in sunflower, corn, and soy oils that
reduces the risk of stroke. However, when consuming
PUFA’s, you must take adequate antioxidants.
PUFA’s are highly subject to oxidation.
A high intake of omega-6 PUFA is associated
with impairment of brain function, perhaps because
of oxidation or the production of arachidonic
acid, a precursor that can lead to increased
inflammation and reduced blood flow.
Other studies point out that the issue is complex.
Research shows that a high intake of total fat,
saturated fat, and cholesterol can nearly double
the risk of dementia, while a high intake of
fish with omega-3 EFA’s decreases the risk
of developing dementia (flaxseeds and walnuts
are other sources of omega-3 fatty acids).
The authors speculate on the mechanisms by
which fat consumption might increase the risk
of brain degeneration. They include atherosclerosis
and thrombosis, inflammation, impaired brain
development, abnormal membrane functioning,
or an accumulation of beta-amyloid, a protein
found in excess in Alzheimer’s disease
(AD).
Although the Western diet is rich in omega-6
oils, and relatively deficient in omega-3 oils,
much of the omega-6 oil comes from highly processed
sources and margarines, of which the former
may already be oxidized, and the latter compromised
by high levels of trans fatty acids. Trans fatty
acids are found in hydrogenated oils, and they
interfere with normal fat metabolism, prostaglandin
production, and membrane structure.
One study on fat and brain function showed
that the risk of AD was doubled for subjects
with the highest level of dietary fat compared
to those with the lowest. The same relationship
was noted between total caloric intake and AD.
These are particular problems in the US, where
fat consumption and total caloric intake are
both high.
In other research, investigators studied the
effects of omega-3 oils and saturated fat on
cognitive function in animals. They found that
if brain blood flow was already low, increased
saturated fat led to further cognitive decline.
On the other hand, in the same study, omega-3
fish oil improved the brain function in animals.
They evaluated the animals by maze testing and
other behavioral measurements.
One of my concerns is that many people are
choosing low carbohydrate diets for weight loss
and other reasons. I agree that refined, simple
carbohydrates (especially sugars and white flour)
are significant problems in the western diet,
and increasingly in other countries, including
China and Japan. However, complex carbohydrates
from whole, unrefined foods are healthy.
Whole, unrefined foods include whole grains,
potatoes, yams or sweet potatoes, winter squashes,
beans, and fresh vegetables and fruits. With
low carbohydrate diets, the only alternative
sources of calories are protein and fats. If
calories are restricted, active people will
lose weight. High fat intake is not healthy,
and loss of brain function is only one of the
risks. (The surest and safest way to lose weight
is to increase exercise while eating whole,
healthy, natural foods.)
Because of the risk of oxidation of dietary
fats, high levels of fruits and vegetables,
particularly those very rich in antioxidants
(such as berries, which I wrote about last month)
are apparently protective of brain function
(as well as reducing heart disease, cancer,
eye disease, and more). Other antioxidant nutrients
that protect the brain include coenzyme Q10,
acetyl L-carnitine, alpha-lipoic acid, N-acetyl
cysteine, ginkgo, bioflavonoids, and proanthocyanidins.
Vitamin E is one antioxidant that helps preserve
brain function. Beta-amyloid is toxic in part
due to free radical damage, which can be controlled
to some extent by vitamin E. In tissue culture,
vitamin E protects brain cells.
However, the study I mentioned on page 1 showed
that supplements of 200 IU of vitamin E, might
prolong respiratory infections or increase symptoms.
While such a study is of concern, many other
human and animal studies suggest the opposite
for influenza, hepatitis, and other infections,
and enhancement of immune function.
I suggest a low-fat diet with adequate amounts
of the EFA’s, with specific EFA’s
added as needed, and nutrient and herb antioxidant
supplements.
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Q. What is the alternative for the treatment
of ulcers? RB, via Email
A. Peptic ulcers are erosions in the stomach
or the duodenum, the first part of the small
intestine, and the disease is often related
to the presence in the stomach of a bacterium
called Helicobacter pylori. Treatment includes
antacid drugs and antibiotic therapy to eliminate
the bacteria. Pepcid, Axid, and Prilosec are
examples of antihistamine antacids, but they
have side effects, and reducing stomach acid
may increase the growth of Helicobacter.
It is important to eliminate the bacteria,
but many other lifestyle changes and dietary
supplements can also help relieve symptoms and
heal the ulcer. Avoid aspirin and other non-steroidal
anti-inflammatory drugs, such as ibuprofen (Advil
or Motrin), which are stomach irritants.
Stress plays a role in hyperacidity and predisposition
to ulcers. Stress reduction, through visualization,
breathing exercises, yoga, meditation, or the
relaxation response may be helpful.
Dietary changes that help include elimination
of caffeine, alcohol, sugar, salt, and white
flour foods, as well as fried foods and highly
processed fast foods. High dietary fiber helps
to absorb stomach acid and reduce damage to
the duodenum, and it prevents the recurrence
of ulcers.
Dietary supplements are very important. L-glutamine,
the main source of energy for intestinal cells,
promotes healing of any gastric inflammation
(2-4000 mg daily). Arginine, another amino acid,
also helps ulcer healing (3-5000 mg).
Heartburn or pain in the upper abdomen or chest
can be relieved with a licorice extract called
DGL (deglycyrrhinizated licorice), which coats
the stomach lining. It also helps relieve acid
reflux symptoms. It must be chewed to be effective.
I also recommend vitamins C (2-6000 mg) and
E (400 IU), zinc (30 mg), quercetin (800 mg)
and other bioflavonoids, plus some vitamin A.
Q. My dad has a blocked
carotid. What can he do without surgery? JL,
W. Virginia.
A. Symptoms of blocked carotid arteries range
from temporary loss of brain function called
a transient ischemic attack (TIA, including
dizziness, weakness, paralysis, or loss of vision,
to a stroke from prolonged lack of brain circulation.
Atherosclerotic carotid arteries require the
same lifestyle changes as heart disease. A low-fat,
high-fiber vegetarian diet plus fish appears
to provide the best nutrition. Typical dietary
supplements include vitamins C (4-6000 mg),
and E (800 IU), magnesium (1000 mg), coenzyme
Q10 (200 mg), and a comprehensive multivitamin
(such as UltraVitality from QCI Nutritionals).
For high cholesterol, he can take octacosanol
(10 mg plus mixed polycosanols), inositol hexaniacinate
(16-2400 mg), gugulipids (500 mg), or red yeast
rice (1000 mg), plus garlic, and fish oils (both
of which also help circulation).
If he has high blood pressure, coQ10 should
help plus hawthorn extract (500 mg), garlic,
and gamma-linolenic acid (240 mg). He should
also start intravenous chelation therapy with
EDTA, shown since the 1950’s to help circulation
to the heart, brain, and legs. Find a doctor
from the American College for Advancement in
Medicine (ACAM), at www.acam.org, or 800-532-3688.
• A new review of women taking hormone
replacement therapy confirms the recent reports
from the Women’s Health Initiative that
they appear to do more harm than good. This
review is of 20,000 women in four different
studies (Beral V, et al., Evidence from randomised
trials on the long-term effects of hormone replacement
therapy. Lancet 2002 Sep 21;360(9337):942-44).
Again, they showed an increased risk of strokes,
breast cancer, and blood clots in women on Premarin
with or without medroxyprogesterone. However,
it is important to note that none of this information
applies to women taking natural (bio-identical)
hormones. Human estrogens and progesterone are
not the same as the typical prescriptions given
to women. Many compounding pharmacies will make
these bio-identical hormones with a doctor’s
prescription.
• Salmonella bacteria are found in significant
numbers in sausages, according to British researchers.
Even if the sausages appear well cooked, they
may still have live bacteria, which can cause
diarrhea, vomiting, and fever (Reuters Health,
September 10, 2002). The bacteria were found
in just under 10 percent of sausages, particularly
in cheap brands. In the report, the public health
doctors said the message is to be sure to cook
your sausages well! Well, that is one possible
message!
• A 28-year Finnish study of 10,000 people
confirms that an apple a day may keep the doctor
at bay (Knekt P, et al., Flavonoid intake and
risk of chronic diseases. Am J Clin Nutr 2002
Sep;76(3):560-8.) Many antioxidant flavonoids
from fruits and vegetables reduce the incidence
of cancer, asthma, diabetes, heart disease,
and strokes. Apples, rich in quercetin, appeared
to provide the greatest risk reduction, but
many other flavonoids, such as kaempferol from
onions, and hesperidin were also beneficial.
I can’t grow avocados or lemons, but I
add my own garden harvest to them for a healthy
dip. Peel and mash up two ripe avocados, juice
one lemon (adjust the amount for your taste),
press one or two cloves of garlic, and mince
a fresh medium tomato and a handful of fresh
cilantro. Add some minced hot pepper if you
like it spicy. Serve this with wedges of whole
wheat pita bread. While you are at the tomatoes,
cilantro, and garlic, (and fresh basil) you
can make that cold gazpacho soup I mentioned
last month. Add to the above ingredients some
diced sweet peppers and cucumber, organic corn,
minced onion and fresh basil, and lemon juice,
with a small amount of tomato juice for liquid.
Add a dash of cumin, pepper, and oregano. Now,
plan a larger garden for next year.
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Solomon PR, et al., Ginkgo for memory enhancement:
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Kirsch I, The Emperor’s New Drugs: An Analysis
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Kalmijn S, Fatty acid
intake and the risk of dementia and cognitive
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Luchsinger JA, et al., Caloric intake and the
risk of Alzheimer disease. Arch Neurol 2002
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de Wilde M, et al., The effect of n-3 polyunsaturated
fatty acid-rich diets on cognitive and cerebrovascular
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Greenwood CE, Winocur G, Learning and memory
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Andreone P, et al., Vitamin E as treatment for
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Katschinski BD, et al.,
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Rees WD, et al., Effect of deglycyrrhizinated
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Rydning A, Berstad A, Dietary aspects of peptic
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Beil W, et al., Effects of flavonoids on...acid
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Tanaka H, et al., Influence of L-glutamine on
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