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Drugs and Grapefruit
Mercury Toxicity
Mercury Protection
Asprin vs. Supplements
Ask Dr. J: Lung Disease (COPD)
References
In the Health News
Diet and Disease
Recipe of the Month: Whole Wheat Cous Cous
Dear Friends,
A recent article suggested that grapefruit sales are down
in part because of physicians’ and patients’ concerns
that grapefruit can interfere with the effect of some drugs,
leading to side effects or excessive activity of those drugs.
I should put quotes around the word “interfere”
because it might just as well read “enhance.”
The common opinion is that grapefruit might be dangerous
for people taking medications. Another view is that eating
grapefruit or drinking grapefruit juice might reduce the doses
of medications that people have to take. Grapefruit blocks
cytochrome P450 enzymes that are involved in drug absorption
and metabolism, often providing a greater effect for the same
dose.
Lowering a dose of medication while maintaining benefit would
be a good effect, not a bad one, as long as it is monitored.
(Of course, this may not be seen as a good thing by the pharmaceutical
companies that will sell less medication.) Some drugs affected
by grapefruit juice include antihistamines, calcium channel
blockers, and drugs for cholesterol (statins), anxiety (Xanax),
hypertension, GERD, depression, and organ rejection.
Doctors and patients need to be in good communication about
this effect (as well as other health care issues). Patients
who are eating grapefruit or drinking the juice need to tell
their doctors and be consistent in their consumption, and
the doctor needs to make appropriate adjustments of the medications
to account for the increased effect. One difficulty is that
the effect can vary from one drug to another and from one
patient to another, but that is true of medications even without
grapefruit.
This is not the only situation in which foods or supplements
might alter medication effects. After my heart valve replacement,
while I had to be on coumadin (an anticoagulant) for a short
time, I was told that I could take vitamin E as long as I
took no more than 400 IU daily. I was informed that higher
doses could enhance the effect of the coumadin, leading to
excessive bleeding risk. Although I did not think this was
likely, I saw the situation from a different perspective.
If vitamin E could enhance the effect of coumadin, in theory
I could take less coumadin and get the same effect if I took
higher doses of vitamin E. This would reduce the cost and
the potential side effects of coumadin.
The medical team was surprised by my view that if you have
a choice it would be better to reduce the medication, and
not automatically tell patients to reduce the dietary supplement.
I continued to take my vitamin E, and noticed no enhancement
of the coumadin effect, but this is not to say it doesn’t
happen. No matter what supplement you take or what drug you
need, it is very important to stay in close communication
with your health care provider because the effects might not
be consistent for some drugs or different people.
Exposure to toxic heavy metals such as lead, mercury, arsenic,
cadmium, and others poses a serious health risk. These metals
poison enzyme systems and damage tissues.
Mercury gets into the environment from mining ore deposits,
coal burning, medical waste incineration, and various manufacturing
plants. It is found in batteries and in dental amalgams (“silver”
fillings).
In the environment, inorganic mercury is converted by bacteria
to methylmercury, which is particularly toxic. Methylmercury
gets into the water supply and is consumed by fish. Larger
fish and scavengers accumulate more mercury.
Mercury sources in humans come from fish, contaminated air
and water, dental amalgams, and immunizations containing thimerosol,
a preservative. Methylmercury (or mercury vapors) damages
the kidneys, brain, and developing fetus, and impairs neurological
development in children. It is also a likely carcinogen.
A number of physicians have associated mercury with the development
of autism in children. High levels may cause or worsen skin
rashes, mental cloudiness, chronic fatigue, nervousness, irritability,
paresthesias (pins and needles), and autoimmune disorders.
Out of over 200 studies on the toxicity of mercury, only
one has suggested that mercury consumption from fish is safe,
and this study is contrary to all of the other data. Of course,
the tuna industry has promoted this study to suggest that
mercury is quite safe during fetal development and childhood,
but it is unwise to base decisions on this one “outlier”
study.
For healthy children and adults, it is important to limit
exposure to heavy metals and to remove the ones that have
already accumulated. The Environmental Working Group (www.ewg.org)
lists the most contaminated fish (tuna, Gulf oysters, sea
bass, halibut, and others) and the least contaminated (wild
salmon, flounder, haddock, farmed trout and catfish, and others).
They point out that the US standards for safety are among
the worst in the world. (Farmed salmon is usually also contaminated
with excessive levels of toxic PCB’s.) However, you
can do a lot to protect yourself from the dangers of mercury
toxicity, as well as the risks of other heavy metal excess.
Your most important protection from mercury and other heavy
metal toxicity is prevention. Avoid excessive immunizations,
especially in children, with thimerosol-preserved vaccines.
Preservative-free vaccines are available for hepatitis and
DTP. If you have tooth decay, have composite fillings instead
of amalgam.
Be careful of other environmental sources, particularly the
listed seafoods. Mercury may be found in household chemicals,
cosmetics, and medications. It is important to eat organic
foods as much as possible to reduce exposure to a variety
of toxic metals and other chemicals.
If you have been exposed to mecury and other heavy metals,
you can be tested for the level of exposure. Everyone has
some of these elements in their system, but they do not always
cause symptoms or chronic problems. The best test is to have
a urine toxic metal screen after taking a dose of a chelating
agent (one that binds with metals and carries them into the
urine).
This challenge test has to be interpreted correctly, as any
chelator will increase the urine level of particular metals,
so the level has to be especially high to suggest toxicity,
and it should be associated with symptoms. If the level is
only moderately elevated, it is important to look for other
causes of the health problems.
Symptoms caused by high mercury levels can be treated with
continued doses of the chelating agents that are used for
the test. I recommend DMSA (dimercaptosuccinic acid) for the
test and treatment. It is effective and has very low risk.
It is also now available without a prescription.
I recommend oral DMSA over intravenous DMPS for mercury and
lead excess, as it is less expensive, and more effective in
protecting the brain.
It is also valuable to take other sulfur-containing supplements,
such as alpha-lipoic acid, and N-acetyl cysteine (NAC) (animal
studies show that it is effective in eliminating methylmercury).
At the same time, I recommend supplements that help detoxify
the body or displace heavy metals, including zinc, selenium,
and vitamin C.
Low-dose aspirin is commonly recommended for prevention of
heart disease and reduction of excessive blood clotting within
the arteries. The benefits in reduction of heart deaths is
outweighed by the complications, unless the risk of a coronary
is high (one percent/year or more; in other words, mainly
patients who have already had a coronary thrombosis).
I have written before about the risks of aspirin, as even
low doses are associated with increased gastrointestinal bleeding.
In one study, doses of 325 mg (one aspirin tablet), 81 mg
(a baby aspirin), or even 10 mg daily all induced significant
gastric mucosal or duodenal damage.
Aspirin also induces kidney damage. Low dose therapy reduces
the ability of the kidneys to clear waste from the blood.
Within just one week of taking daily aspirin, uric acid and
creatinine clearance are impaired. Creatinine clearance stayed
low even a week after stopping aspirin.
Aspirin is effective at reducing platelet adhesiveness. Platelets
initiate blood clotting by clumping together when they are
disturbed in several ways, but other substances also reduce
platelet stickiness without side effects. Grape flavonoids
reduce platelet clumping by 77 percent. Vitamins C and E (mixed
tocopherols only) significantly reduce platelet aggregation.
Ginkgo biloba inhibits platelet activating factor. In addition,
120 to 240 mg of standardized extract reduces claudication,
improves memory and mood in Alzheimer’s patients, and
relieves tinnitus. It also contains potent antioxidants.
Platelet aggregation is inhibited by garlic, curcumin, ginseng,
ginger, fish oil and other natural and safe substances. Animal
fat increases platelet aggregation. Aspirin is unnecessary
if you attend to your diet and supplements.
Q. What would be a good
supplement or supplements for COPD and the accompanying shortness
of breath? CC, via email
A. Chronic obstructive pulmonary disease,
or COPD, is the result of chronic damage to the lining of
the lungs, usually from smoking, but also from other causes,
such as chronic bronchitis. It is commonly associated with
emphysema, an irreversible destruction of the air sacs (alveoli)
and loss of elasticity of the lungs.
Shortness of breath is the primary symptom of COPD, and severity
is determined by how much air someone can force out in one
second (FEV1). Treatment is with drugs to dilate the bronchi
and thin the mucus secretions, and steroids.
A high-fat diet increases the symptoms. Eat lots of fruits
and vegetables for their antioxidant components. Also, take
supplements that help mucous membranes and reduce shortness
of breath, including vitamin C (4 gms/d), vitamin E (400 to
800 IU of mixed tocopherols), gamma-linolenic acid (240 mg
from borage oil), omega-3 fatty acids (fish oil and flaxseed
oil), and a variety of flavonoids (1 to 2 gms). N-acetyl cysteine
(NAC, 1 to 2 gm) helps loosen secretions and is a good antioxidant.
Lung function is a significant predictor of mortality, so
it is important to avoid smoke and air pollution and follow
healthy supplement guidelines and a low-fat diet.
Lohezic-Le Devehat F, et al., Grapefruit
juice and drugs... Therapie 2002 Sep-Oct;57(5):432-45.
Why grapefruit sales are souring. Wall
St. Journal, July 17, 2003
Forman J, et al., ...mercury exposure cases
treated with ... (DMSA) Environ Health Perspect. 2000 Jun;108(6):575-7.
Fournier L, et al., [DMSA] treatment of
heavy metal poisoning... Med Toxicol Adverse Drug Exp. 1988
Nov-Dec;3(6):499-504.
Aaseth J, et al., Treatment of mercury
and lead poisonings with
[DMSA] and [DMPS]. A review. Analyst 1995 Mar;120(3):853-4.
Ballatori N, et al., N-acetylcysteine as
an antidote in methylmercury poisoning. Environ Health Perspect
1998 May;106(5):267-71.
Sanmuganathan PS, et al., Aspirin for primary
prevention of coronary heart disease: safety and absolute
benefit... Heart 2001 Mar;85(3):265-271.
Cryer B, Feldman M, Effects of very low
dose...aspirin therapy on...mucosal injury... Gastroenterology
1999 Jul;117(1):17-25.
Caspi D, et al., The effect of mini-dose
aspirin on renal function...in elderly patients. Arthritis
Rheum 2000 Jan;43(1):103-8.
Keevil JG, et al., Grape juice, but not
orange juice or grapefruit juice, inhibits human platelet
aggregation. J Nutr 2000 Jan;130
(1):53-6.
Schindler TH, et al., Effect of vitamin
C on platelet aggregation in smokers and nonsmokers. Med Klin
2002 May 15;97(5):263-9.
Akiba S, et al., Inhibitory effect of the
leaf extract of Ginkgo biloba L. on oxidative stress-induced
platelet aggregation. Biochem Mol Biol Int 1998 Dec;46(6):1243-8.
Srivastava KC, et al., Curcumin...inhibits
aggregation...in...platelets. Prostaglandins Leukot Essent
Fatty Acids 1995 Apr;52
(4):223-7.
Verma SK, et al., Effect of ginger on platelet
aggregation in man. Indian J Med Res 1993 Oct;98:240-2.
Legnani C, et al., Effects of...garlic...on...platelet
aggregation in healthy subjects. Arzneimittelforschung 1993
Feb;43(2):119-22.
Liu M, et al., Mixed tocopherols inhibit
platelet aggregation in humans... Am J Clin Nutr 2003 Mar;77(3):700-6
A new study in Japan shows that supplements of the hormone
DHEA (dehydroepiandrosterone) can improve blood vessel function
and increase insulin sensitivity. Taking 25 mg of DHEA enhances
blood flow through the arteries by protecting the endothelium,
reduces sugar levels in the blood without changing insulin
levels, and lowers the amount of plasminogen activator inhibitor,
preventing excessive blood clotting. These changes all have
the potential to reduce the risk of heart disease and diabetes.
(Kawano H, et al., Dehydroepiandrosterone
supplementation improves endothelial function and insulin
sensitivity in men. J Clin Endocrinol Metab 2003 Jul;88(7):3190-5.)
The Environmental Working Group has issued a warning about
the dangerous levels of PCB’s found in farmed salmon
(http://www.ewg.org/reports/farmedPCBs/es.php).
PCB’s (polychlorinated biphenyls) are doxin-like chemicals
that are carcinogenic, impair neurological development in
children, particularly if they are exposed during pregnancy,
and damage immune function. EWG found high levels in 70 percent
of the tested fish, with 16 times as much PCB’s as the
safer wild salmon. PCB’s accumulate in farmed salmon
because of their diet and the fattening-up process used to
increase their sale weight.
The UN Food and Agriculture Organization and the World Health
Organization advice on diet to governments (Reuters,
March 2003) says that to prevent heart disease, diabetes,
cancer, and obesity people should get most of their calories
from complex carbohydrates, eat adequate but not high protein,
and reduce sugar calories to less than 10 percent of the diet
(this amount of dietary sugar is less than half that of the
typical American diet).
Cous cous is a traditional North African dish made with a
small, round pasta that is commonly made from refined wheat,
but is available as whole wheat. It is easy to make a vegetarian
version. Sauté onions, crushed garlic, and ginger with
olive oil. Turn off the heat, and add cooked chick peas plus
diced tomatoes, carrots, peppers, and summer squash. Boil
a cup of whole wheat cous cous in 1 1/2 cup of vegetable broth
(it only takes a few minutes), add the cooked vegetables,
and simmer until the broth is absorbed. Add chopped cilantro
and season the dish with lemon or lime, cumin, and black or
cayenne pepper. You can use other vegetables, such as cauliflower.
You can make this dish with millet instead of cous cous. Boil
a cup of millet in 2 cups of vegetable broth until most is
absorbed, then proceed as above. Either way, this dish is
tasty and nutritious.
drjanson@drjanson.com
November
through May: 386-409-7747
June
through October: 603-878-2256
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