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Coenzyme Q10 and migraine
Low-carb/high protein diets
Low protein reduces cancer risks
Exercise lowers breast cancer risk
Diet reduces prostate cancer risk
Benefits of lignans and soy isoflavones
Ask Dr. J: Healthy Weight Gain
Supplements of Coenzyme Q10 help migraine headaches. In
a double-blind, placebo controlled study of 42 migraine patients,
subjects received either 300 mg of coenzyme Q10 per day or
a placebo. Within three months, treatment led to a reduction
in the frequency of headaches, the number of days with nausea,
and the number of headache days. Treatment produced no side
effects. Half of the subjects in the treatment group had
fewer headaches, compared with only 14 percent in the placebo
group (Sandor PS, et al., Efficacy of coenzyme Q10 in migraine
prophylaxis: a randomized controlled trial. Neurology. 2005
Feb 22;64(4):713-5.)
A new study of diet suggests that low-carbohydrate diets
do not raise the risk of heart disease. The Nurses’ Health
Study examined the effects of different nutritional combinations
among 82,202 women over a period of 20 years. The researchers
did find that the quality of the carbohydrate and the source
of the protein and fat were significant. (Halton TL, et al.,
Low-carbohydrate-diet score and the risk of coronary heart
disease in women. N Engl J Med. 2006 Nov 9;355(19):1991-2002.)
This study compared those subjects with the lowest carbohydrate
intake (bottom 10 percent) with those who had the highest
intake (top 10 percent) and evaluated the incidence of heart
disease. One problem with this method is that the researchers
used total caloric intake as carbohydrate without distinguishing
the amounts of sugar and white flour versus the intake of
whole grains, beans, and fruits, and other high-fiber sources
of carbohydrate.
As a result, any purported benefits from consuming “low
carbohydrates” could be totally due to the reduced
intake of sugar and white flour and other refined grains
or sweeteners. One effect of this would be to conceal the
dangers of high-protein diets when compared to high-carbohydrate
diets rich in whole grains, beans, vegetables and fruits.
Numerous studies have shown reduced disease and mortality
when adding whole grains and other unrefined carbohydrate
sources to the diet. (Lang R, Jebb SA, Proc Nutr Soc. 2003
Feb; 62(1): 123-7; Steffen LM, et al. Am J Clin Nutr. 2003
Sep;78(3):383-90; Jacobs DR Jr, et al., Am J Public Health.
1999 Mar;89(3):322-9; Liu S, J Am Coll Nutr 2002 Aug;21(4):298-306;
Liu S, A J Clin Nutr 1999;70:307-308,412-419; Cotterchio
M, et al., J Nutr. 2006 Dec; 136(12):3046-53; and others.)
These studies show that the rate of heart disease, diabetes,
and a variety of cancers are reduced by whole grains, legumes,
fruits and vegetables.
It appears from this and other research that fiber, flavonoids,
antioxidants, and other phytochemicals found in unrefined
carbohydrate foods are protective. Another finding in the
current study was that all of the apparent benefit of the
lower-carbohydrate diets resulted if the sources of the protein
and fat in the diet were vegetarian.
A new study suggests mechanisms by which a low protein diet
might reduce the risk of cancer. (Fontana L, et al., Long-term
low-protein, low-calorie diet and endurance exercise modulate
metabolic factors associated with cancer risk. Am J Clin
Nutr. 2006 Dec;84(6): 1456-62.) The researchers noted that
long-term, low-protein or low-calorie diets, as well as endurance
exercise, are associated with a lower incidence of cancer.
The researchers found that those on low protein or low calorie
intake, or exercisers had lower levels of insulin, inflammatory
markers such as CRP, and sex hormones. In the low-protein
and low-calorie groups, growth factors such as IGF-1 (insulin-like
growth factor) were lower, but these were not influenced
by exercise. These plasma markers are all associated with
increased cancer risk. Only the dietary changes influenced
all the markers.
In the Iowa Women’s Health Study of 41,836 post-menopausal
women, a new analysis shows that recreational exercise lowers
the risk of breast cancer. (Bardia A, et al., Recreational
Physical Activity and Risk of Postmenopausal Breast Cancer
Based on Hormone Receptor Status. Arch Intern Med. 2006 Dec
11;166(22):2478-83.) Those women who did the most exercise
had a 15 percent lower risk of breast cancer than those who
did the least exercise, and the risk of estrogen receptor
positive tumors was similarly reduced. These are the riskiest
tumors. Some estrogen sensitive tumors had a 44 percent lower
risk.
A review article in a German scientific journal concluded
that dietary choices and dietary supplements could reduce
the risk of prostate cancer. (Theobald S. Nutrition and prostate
cancer--what is the scientific evidence? Med Monatsschr Pharm.
2006 Oct;29(10):371-7.) The author noted that a high intake
of total fat, saturated fats, meat, dairy, and calcium were
associated with an increased risk of prostate cancer.
Conversely, lower risk was seen with a high intake of tomato
products, soy, lycopene (a carotenoid found in tomato, watermelon,
red grapefruit and red navel oranges), selenium, omega-3
oils from fish, and vitamin E (in smokers). Also, supplements
of tomato derivatives and selenium could slow the progression
of tumor growth. The author also noted that selenium supplements
could reduce the toxicity of chemotherapy and enhance its
effectiveness.
Plant compounds that have mild estrogen-like activity include
isoflavones, present in a variety of beans, especially soybeans,
and lignans found in grains, fruits, nuts, some vegetables,
and seeds (especially flaxseeds). These substances have a
variety of health benefits.
New research on 2985 subjects shows that those with the
highest lignan intake had a 27 percent lower risk of colo-rectal
cancer, while those with the highest isoflavone intake had
a 29 percent lower risk, compared to those with the lowest
intake of the two substances. (Cotterchio M, et al., Dietary
phytoestrogen intake is associated with reduced colorectal
cancer risk. J Nutr. 2006 Dec;136(12):3046-53.) Other research
shows a lowered risk of breast and prostate cancers.
While some writers have expressed concerns about the possible “dangers” of
soy intake, the evidence continues to accumulate that typical
dietary amounts of minimally processed soy products (such
as tofu, soymilk, and tempeh) have a variety of health benefits.
Setchell evaluated the risks and benefits of soy intake in
2001 (Setchell KD, Soy isoflavones--benefits and risks from
nature's selective estrogen receptor modulators (SERMs).
J Am Coll Nutr. 2001 Oct;20(5 Suppl):354S-362S). He estimated
that soy food intake among Asian adults ranges from 2 to
4 ounces per day, providing 7 to 14 grams of soy protein,
and 15 to 70 mg of isoflavones daily.
Isoflavones contribute to lowered cholesterol, reduced atherosclerosis,
and improved blood vessel reactivity (greater relaxation
and dilation of the arteries leading to improved blood flow:
Honore EK, et al., Fertil Steril. 1997 Jan;67(1):148-54.).
Other studies indicate that soy isoflavones limit bone turnover
and reduce post-menopausal bone loss. They are also antioxidant
and anti-inflammatory.
Some animal studies suggesting problems with soy ignored
the species differences in metabolism of isoflavones (the
cat family, for example, lacks an enzyme to help metabolize
the phytoestrogens so these have much greater hormonal effects
in cats than in humans). Other problems are due to the ingestion
of extremely high amounts of phytoestrogens that go far beyond
the typical human dietary intake.
The concern about thyroid inhibition is based on test-tube
studies of the blockage of an enzyme that is required for
thyroid hormone production (thyroid peroxidase), but the
levels of isoflavones required to show this negative effect
are extremely high, and again unrelated to typical soy food
consumption in humans. (This enzyme is also inhibited by
other flavonoids commonly present in many fruits and vegetables,
but they do not have adverse effects either).
While breast milk is the ideal food for infants, those who
are fed soy formula do not have evidence of thyroid problems
(retardation of growth and development). This suggests that
isoflavones do not lead to significant thyroid inhibition.
Still, it is best for brain development if infants are breast
fed so they would get the omega-3 fatty acids present in
breast milk.
Finally, some writers and medical colleagues have suggested
that Asians do not eat as much soy food as has been thought.
The numbers noted above are one indication that for adults
in Asia soy intake is moderately high (and very high compared
to typical Western diets). During my visits to Japan for
consulting, I have found that soy foods are readily available
in grocery stores and served in most restaurants. I have
eaten at restaurants that specialize in numerous ways to
prepare soy foods.
Soy consumption in Asia now has a lot of competition with
more abundant and affordable supplies of meat and dairy,
and the transition to more animal products and less soy is
associated with an increase of some diseases, such as heart
disease as well as increasing average body weight. I am not
a proponent of texturized soy protein or any other highly
processed and adulterated foods, but minimally processed
soy, such as tofu, tempeh, and soy milk are healthful.
Q: How can I gain weight in a healthful way, without having
to eat lots of ice cream and overloading the diet with excessive
amounts of fat?
KK, Netherlands, via Internet
A: It is not often that I have questions on how to gain
weight, as overweight and obesity are far more common problems
in industrialized cultures. However, a significant number
of people do have problems with being underweight.
It is important first to make sure there is no underlying
health issue, such as malabsorption, infectious diseases,
hyperthyroidism, liver problems, or malignancies. If none
of these is the issue, you can gain weight healthfully by
some dietary choices and a combination of regular exercises.
Include extra oily foods that contain healthful essential
fatty acids. These include avocados (added to salads or as
guacamole), sesame tahini (in salad dressings, vegetable
dips, or in hummus – a chick pea dip, and baba ghanouj – an
eggplant dip), and seeds and nuts. Peanuts and soybeans are
the highest legumes in fat content, so tofu and peanut butter
might help. Also, coconut is healthful and relatively high
in calories. Add it to smoothies or use some coconut milk
in sautéed vegetables with brown rice.
You can also include olive oil and flaxseed oil in your
diet as part of salad dressings or drizzled over vegetables
and potatoes. It is helpful to eat frequently, with nutritious
between meal snacks, and it may help to take pancreatic digestive
enzymes.
Regular exercise and weight lifting to build muscle will
help make sure that you are putting on muscle as well as
gaining some fat weight. Increasing muscle mass is important
for general health, longevity, and blood sugar control.
drjanson@drjanson.com
Practice phone: 603-878-2256
180 Massachusetts Ave., Suite 303
Arlington, MA 02474
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