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Healthy Low-Fat Diets
Tea: Green, Black, and Red
Caffeine-Free Red Tea
Hot Pepper and Cancer
Ask Dr. J: Arthritis and Food
References
In the Health News
Diet and Disease
Recipe of The Month: Millet Apricot-Date Cake
Dear Friends,
Not so fast! Wait before believing news about diets. In commenting
on scientific data regarding health care, and especially nutrition
and alternative medicine, the news media is apt to jump to
conclusions, and false ones at that. This can almost be forgiven
when even the researchers who do the studies and the editorialists
of the journals that publish them make similar erroneous claims.
I wonder if the journals benefit from sensational reporting.
Recently, this was evident in the widespread reporting of
several studies of diet that “clearly” showed
that no benefits in terms of reduction of heart disease or
cancer could be achieved by following a low-fat diet. The
only problem with the studies and the hoopla surrounding them
was that they did not actually study low-fat diets! What they
really studied was a comparison of a high-fat diet with a
very-high-fat diet. Maybe it is just that people (including
the news reporters) love to hear good things about their bad
habits.
These studies were derived from the Women’s Health
Initiative (WHI), in which 48,835 post-menopausal women participants
were asked to stay on the same diet they were on, which was
about 37 percent fat (the level in the standard American diet,
or SAD diet), or follow a suggested diet containing only 20
percent fat. This would have been reasonable enough (although
even lower fat diets have been shown to be even more helpful),
but the group on the lower fat wing of the study were not
successful in staying on their suggested diets, and only achieved
a reduction to an average 29 percent fat, which is still higher
than levels shown to be healthful in other studies. You can
hardly expect people to benefit from a diet when they do not
follow it. The intervention group was supposed to increase
fruits and vegetables to five, and grains to six servings,
but they barely increased them.
The Mediterranean diet is relatively high fat, but heart
disease is much lower than found in countries on diets with
similar fat intake, but the wrong kinds of fat. The olive
oil in the Mediterranean diet is much healthier than the animal
fats, processed oils, and margarines consumed in the United
States and some other industrialized countries. Still, the
rate of heart disease seen in populations on the Mediterranean
diet is higher than in Japan, where the diet is lower in fat
(although this is sadly changing in Japan and other countries
as they begin to follow the Western diet and incorporate more
processed foods and junk, and yes, more fat).
Some good news about low-fat diets did come out of these
studies, but this was barely reported. Women who started with
the highest fat diets but lowered fat intake the most had
the greatest reduction of breast cancer risk. Also, women
with the lowest fat intake had the lowest risk of heart disease.
Colon polyps that precede cancer were reduced with the lowest
fat intake. The real lesson of these studies is that low-fat
diets are healthful, but you would never know it by reading
the headlines.
Aside from non-commercial water, tea is the most consumed
beverage in the world (60 billion gallons in 1999), and it
is far ahead of the rest, including carbonated soft drinks
(which have recently surpassed milk), bottled water, beer,
and coffee. The tea plant, Camellia sinensis, provides the
leaves that have been consumed as tea for nearly 5000 years,
originally in China.
Green tea leaves are steamed before being dried, while black
tea is the result of fully oxidizing the tea leaves. The resulting
flavonoid content of the two differs in that green tea has
4-10 times as much catechin as black tea, as well as other
differences in flavonoid content. Green tea contains theanine,
a relaxing amino acid that also has benefits in cancer treatment.
Tea contains a number of healthful components, including
catechins (a group of polyphenols including epigallocatechin
gallate, or EGCG), and flavonols. These act as antioxidants,
protecting LDL cholesterol from oxidation and in animal studies
provide some protection from cancer metastases. When fed to
mice, these substances both delay the onset and reduce the
total number of tumors. They also induce programmed cell death
in cancer cells and inhibit proliferation.
Men with prostate cancer precursor cells (high-grade intra-epithelial
neoplasia) have a 30 percent chance of developing prostate
cancer within one year. A double-blind study of 60 men with
these cells showed that administration of 600 mg daily of
green tea catechins for one year reduced the development of
prostate cancer. Only one subject of the 30 in the treatment
group developed prostate cancer, while nine men in the placebo
group developed the disease. In men who also had symptoms
of prostate enlargement, treatment significantly reduced their
symptoms.
In animal studies, both green and black teas have anti-inflammatory
effects. One report showed inhibition of inflammation and
reduction signs of polyarthritis in a laboratory model of
the disease. Other studies show that black tea can reduce
cardiovascular disease and improve endothelial function, possibly
due to some of the flavonoids rather than the catechins. Healthy
endothelial function lowers cardiovascular risk, partly by
lowering blood pressure.
EGCG also displays anti-inflammatory effects in the brain,
and exerts some neuroprotective properties in animal models
of brain auto-immune disorders similar to MS. Administered
orally, ECGC reduced the condition when given at the onset
or later in the course of the disease and blocked free-radical
neuronal damage.
In cell cultures, EGCG and tea theaflavins also inhibit viral
infections. These protect from both respiratory viruses and
HIV, blocking both viral replication and cell invasion through
a variety of mechanisms.
One problem with drinking tea is the caffeine content. Coffee
may contain from 30-50 mg/oz (espresso) to 135 mg per 8-ounce
cup (12 oz. is a more realistic serving size, and might contain
200 mg or more). Tea has far less, but still significant amounts.
A 12-oz. cup of black tea contains about 60-100 mg of caffeine,
and green tea from 40-60 mg. These are significant doses of
this central nervous system stimulant and diuretic, and may
cause side effects in many people. Decaffeinated teas are
available, but may lose protective compounds in processing.
Supplements usually have no caffeine. Typical supplements
of green tea contain 200 mg of standardized extract.
Red tea is not true tea, as it comes from a different plant
altogether. It is the pine-needle-like leaf of a South African
red bush (rooibos, or Aspalathus linearis) and is naturally
free of caffeine. The leaves are usually fermented to a rich
reddish-brown color and then dried, and the “tea”
(or herbal infusion) retains the same color. Unfermented dried
leaves are also available (they are a yellow-beige color).
Rooibos does contain many antioxidant flavonoids and polyphenols,
similar to both green and black teas, and they also contain
healthful polysaccharides.
Laboratory and animal studies confirm many of the same benefits
as are found with green and black teas, but few human studies
are published. In one lab study, polysaccharides in rooibos
inhibited HIV activity. Rooibos extracts suppress skin cancer
cells in mice and protect against radiation damage, and peroxidation
of brain lipids, which might block the development of degenerative
brain disorders. It is good that rooibos is a very tasty tea,
as supplements are not available.
Capsaicin is the substance in hot peppers that makes them
hot. Recent studies suggest that capsaicin might help in prevention
and treatment of prostate and gastric cancers. In laboratory
cell studies, capsaicin inhibits the proliferation of prostate
cancer cells, both those that are sensitive to androgens and
those that are not. It also induces apoptosis, or programmed
cell death, in the cancer cells. (Mori A, et al., Capsaicin,
a Component of Red Peppers, Inhibits the Growth of Androgen-Independent,
p53 Mutant Prostate Cancer Cells. Cancer Res. 2006 Mar 15;66(6):3222-9.)
The same researchers reported in that study on their treatment
of mice grafted with prostate cancer cells. When the mice
were treated orally with capsaicin, tumor growth as measured
by size was reduced by 70 percent, and as measured by weight
by 40 percent. Overall, capsaicin had a number of beneficial
effects on tumor promotion, hormone sensitivity, PSA production
and activity, and other tumor growth factors.
Another study showed that capsaicin induced cell death in
gastric cancer cells under laboratory conditions. Treatment
of the cell lines resulted in an increase in apoptosis and
fragmentation of DNA. Evidence of cell death was directly
correlated with the dose of capsaicin. (Lo YC, et al., Capsaicin-induced
cell death in a human gastric adenocarcinoma cell line. World
J Gastroenterol. 2005 Oct 28;11(40):6254-7.)
Both of these studies are strongly suggestive that hot peppers
offer cancer protection. Capsaicin is also helpful for inflammation,
heart disease, and arthritis pain relief (topical application),
as well as protection of the gastric mucosa from ulcers.
Q. I have arthritis. What foods should I avoid to prevent
inflammation? I take fish oil, calcium, glucosamine, vitamin
C, and a multi daily.
JS, via email
A. Some people have suggested that foods from the nightshade
family, such as potatoes, tomatoes, peppers, and eggplants
might contribute to arthritis, but I have not found this to
be true for most patients. However, some foods might increase
inflammation, and others might reduce it.
Foods that contain land animal fat might increase inflammation
because of the arachidonic acid that they contain (this is
a non-essential fatty acid found in meat and poultry, as well
as milk, and is a precursor of prostaglandin E2, which promotes
inflammation). Trans fatty acids, from hydrogenated vegetable
oils such as margarine and shortening, also increase inflammation.
A diet high in fruits and vegetables is associated with reduced
inflammation, but it is not clear which specific components
are responsible.
The fish oil that you take and the vitamin C may both help
to reduce inflammation and reduce arthritis pain. Olive oil
and gamma-linolenic acid (from evening primrose or borage
oils) enhance the anti-inflammatory effect of fish oil. Vitamin
E (800-1200 IU daily) also lowers the markers of inflammation,
such as CRP, by up to 50 percent.
A number of supplements also help reduce the inflammation
or pain associated with arthritis. Curcumin, a turmeric extract
(300-600 mg), ginger (250-750 mg), and boswellia (400-600
mg) can all help with arthritis. S-adenosyl methionine (SAMe)
is beneficial in both osteoarthritis and rheumatoid arthritis
(200-600 mg). Some combination of a healthy diet and these
supplements should be helpful.
Low-fat dietary pattern... JAMA. 2006 Feb
8;295(6) [Three separate studies published in the same issue]
Thangapazham RL, et al., Green tea polyphenols
and its constituent epigallocatechin gallate inhibits proliferation
of human breast cancer... Cancer Lett. 2006 Mar 3; [Epub ahead
of print]
Peng G, et al., Green tea polyphenol (-)-epigallocatechin-3-gallate
inhibits cyclooxygenase-2 expression in colon carcinogenesis.
Mol Carcinog. 2006 Feb 28; [Epub ahead of print]
Siddiqui IA, et al., Beneficial effects
of tea and its polyphenols against prostate cancer. Mol Nutr
Food Res. 2006 Feb;50(2):130-43.
Bettuzzi S, et al., Chemoprevention of human prostate cancer
by oral administration of green tea catechins... Cancer Res.
2006 Jan 15;66(2):1234-40.
Nag Chaudhuri AK, et al., Anti-inflammatory
activity of Indian black tea (Sikkim variety). Pharmacol Res.
2005 Feb;51(2):169-75.
Widlansky ME, Effects of black tea consumption
on plasma catechins and markers of oxidative stress and inflammation...Free
Radic Biol Med. 2005 Feb 15;38(4):499-506.
Duffy SJ, et al., ...black tea consumption
reverses endothelial dysfunction... Circulation. 2001 Jul
10;104(2):151-6.
Aktas O, et al., [EGCG]...exerts neuroprotection
in autoimmune encephalomyelitis. J Immunol. 2004 Nov 1;173(9):5794-800.
Weber JM, Inhibition of adenovirus infection
and adenain by green tea catechins. Antiviral Res. 2003 Apr;58(2):167-73.
Fassina G, et al., [EGCG] from green tea
as a candidate anti-HIV agent. AIDS. 2002 Apr 12;16(6):939-41.
Liu S, et al., Theaflavin derivatives in
black tea and catechin derivatives in green tea inhibit HIV-1
entry by targeting gp41. Biochim Biophys Acta. 2005 May 25;1723(1-3):270-81.
Nakano M, et al., Anti-human immunodeficiency
virus activity of oligosaccharides from rooibos tea (Aspalathus
linearis) extracts in vitro. Leukemia. 1997 Apr;11 Suppl 3:128-30.
Marnewick J, et al., Inhibition of tumour
promotion in mouse skin by extracts of rooibos... Cancer Lett.
2005 Jun 28;224(2):193-202.
a. A combination of standardized extracts of St. John’s
wort (1 mg hypericin) and black cohosh (4 mg triterpene glycosides)
helps women with menopausal symptoms, including hot flashes
and depression. In a placebo-controlled study of 301 symptomatic
menopausal women for 4 months, the herbal combination reduced
symptoms of depression by 42 percent and menopausal symptoms
were cut in half. (Uebelhack R, et al., Black cohosh and St.
John’s wort for climacteric complaints: a randomized
trial. Obstet Gynecol. 2006 Feb;107(2 Pt 1):247-55.) The subjects
had no side effects and tolerated the treatment well.
b. Elderly people require 20 percent more energy and oxygen
to perform the same activity as younger adults, but this appears
not to be due to age itself, but to lack of training from
sedentary lifestyles. When elderly people were put on a 6-month
exercise training program, with jogging, bicycling, or walking,
and stretching, for 90 minutes 3 times a week, their capacity
improved 30 percent. (Woo JS, et al., The influence of age,
gender, and training on exercise efficiency. J Am Coll Cardiol.
2006 Mar 7;47(5):1049-57.) Training completely reversed the
age-associated decline in exercise efficiency.
Glycemic index or glycemic load (the effect of a food on blood
sugar) are not good guides to dietary choices. In 813 subjects
over five years, GI or GL were not associated with changes
in blood sugar indicators. The glycemic effect of a food is
different in real-life conditions than during testing, depending
on when it is eaten, with what else, how it is cooked, and
other variables (Mayer-Davis EJ, et al., Towards understanding
of glycaemic index and glycaemic load...Br J Nutr. 2006 Feb;95(2):397-405).The
best course is to choose high-fiber foods that are low in
fat, including lots of fruits, vegetables, whole grains, and
beans. This can include potatoes.
Put a cup of millet, 3 cups of water, and 1/2 tsp of salt(optional)
in a saucepan, bring to a boil, then turn it off to cool while
in a large bowl you mix 1/4 cup of chopped organic dried apricots,
1/4 cup of chopped dates, 1/2 cup of organic raisins, 1/4-1/2
cup of shredded coconut, 1 tsp of cinnamon, and 1/2-1 tsp
of freshly ground nutmeg. Add 1/4 cup of maple syrup and/or
honey and 1/2-1 Tbsp of vanilla extract. You can add 2-3 mashed
bananas at this point as an option. Blend the watery millet
in a food processor until creamy (about a minute), add this
to the other ingredients in the bowl, and mix well. Place
the mix in an oiled loaf pan and bake at 350 for about 75
minutes (up to 90 minutes if you add the bananas). Let it
cool, as it will set during this time. Remove it from the
loaf pan and cut slices to serve with fresh or frozen berries
(I defrost frozen organic blueberries and strawberries).
drjanson@drjanson.com
Practice phone: 603-878-2256
180 Massachusetts Ave., Suite 303
Arlington, MA 02474
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