--- [log in to unmask] wrote:
>What about the cancer and heart-protective attributes
of catechins,
>which chocolate products have become increasingly
associated with? >Again
- >in isolation, polyphenols work well in a test-tube
environment, but
>cocoa also happens to be very high in Copper, which
unfortunately
>inhibits the action of some flavonoids, particularly
hesperidin, which >is an essential flavanone.”
Eades says we as paleo eaters, need to find a copper
source, as our diets are very high in zinc due to the
high levels of meat we consume. In the article I
read, he mentioned chocolate as a source.
There are tons of studies on pubmed that show a
substantial benefit from consuming the flavonoids in
chocolate. I couldn't find one that found a problem
with copper toxicity. It may be because the groups
that consume large amounts of cocoa are not typically
lare consumers of grains, which are also high in
copper.
I pasted a few below of the pubmed abstracts
below.....
Substantial data suggest that flavonoid-rich food
could help prevent cardiovascular disease and cancer.
Cocoa is the richest source of flavonoids, but current
processing reduces the content substantially. The Kuna
living in the San Blas drink a flavanol-rich cocoa as
their main beverage, contributing more than 900 mg/day
and thus probably have the most flavonoid-rich diet of
any population. We used diagnosis on death
certificates to compare cause-specific death rates
from year 2000 to 2004 in mainland and the San Blas
islands where only Kuna live. Our hypothesis was that
if the high flavanoid intake and consequent nitric
oxide system activation were important the result
would be a reduction in the frequency of ischemic
heart disease, stroke, diabetes mellitus, and cancer -
all nitric oxide sensitive processes. There were
77,375 deaths in mainland Panama and 558 deaths in the
San Blas. In mainland Panama, as anticipated,
cardiovascular disease was the leading cause of death
(83.4 +/- 0.70 age adjusted deaths/100,000) and cancer
was second (68.4 +/- 1.6). In contrast, the rate of
CVD and cancer among island-dwelling Kuna was much
lower (9.2 +/- 3.1) and (4.4 +/- 4.4) respectively.
Similarly deaths due to diabetes mellitus were much
more common in the mainland (24.1 +/- 0.74) than in
the San Blas (6.6 +/- 1.94). This comparatively lower
risk among Kuna in the San Blas from the most common
causes of morbidity and mortality in much of the
world, possibly reflects a very high flavanol intake
and sustained nitric oxide synthesis activation.
ACKGROUND: Cocoa powder is rich in polyphenols such as
catechins and procyanidins and has been shown in
various models to inhibit LDL oxidation and
atherogenesis. OBJECTIVE: We examined whether
long-term intake of cocoa powder alters plasma lipid
profiles in normocholesterolemic and mildly
hypercholesterolemic human subjects. DESIGN:
Twenty-five subjects were randomly assigned to ingest
either 12 g sugar/d (control group) or 26 g cocoa
powder and 12 g sugar/d (cocoa group) for 12 wk. Blood
samples were collected before the study and 12 wk
after intake of the test drinks. Plasma lipids, LDL
oxidative susceptibility, and urinary oxidative stress
markers were measured. RESULTS: At 12 wk, we measured
a 9% prolongation from baseline levels in the lag time
of LDL oxidation in the cocoa group. This prolongation
in the cocoa group was significantly greater than the
reduction measured in the control group (-13%). A
significantly greater increase in plasma HDL
cholesterol (24%) was observed in the cocoa group than
in the control group (5%). A negative correlation was
observed between plasma concentrations of HDL
cholesterol and oxidized LDL. At 12 wk, there was a
24% reduction in dityrosine from baseline
concentrations in the cocoa group. This reduction in
the cocoa group was significantly greater than the
reduction in the control group (-1%). CONCLUSION: It
is possible that increases in HDL-cholesterol
concentrations may contribute to the suppression of
LDL oxidation and that polyphenolic substances derived
from cocoa powder may contribute to an elevation in
HDL cholesterol.
A single-dose ingestion of flavanol-rich cocoa acutely
reverses endothelial dysfunction. To investigate the
time course of endothelial function during daily
consumption of high-flavanol cocoa, we determined
flow-mediated dilation (FMD) acutely (for up to 6
hours after single-dose ingestion) and chronically
(administration for 7 days). The study population
represented individuals with smoking-related
endothelial dysfunction; in addition to FMD, plasma
nitrite and nitrate were measured. The daily
consumption of a flavanol-rich cocoa drink (3 x 306 mg
flavanols/d) over 7 days (n=6) resulted in continual
FMD increases at baseline (after overnight fast and
before flavanol ingestion) and in sustained FMD
augmentation at 2 hours after ingestion. Fasted FMD
responses increased from 3.7 +/- 0.4% on day 1 to 5.2
+/- 0.6%, 6.1 +/- 0.6%, and 6.6 +/- 0.5% (each P <
0.05) on days 3, 5, and 8, respectively. FMD returned
to 3.3 +/- 0.3% after a washout week of cocoa-free
diet (day 15). Increases observed in circulating
nitrite, but not in circulating nitrate, paralleled
the observed FMD augmentations. The acute, single-dose
consumption of cocoa drinks with 28 to 918 mg of
flavanols led to dose-dependent increases in FMD and
nitrite, with a maximal FMD at 2 hours after
consumption. The dose to achieve a half-maximal FMD
response was 616 mg (n=6). Generally applied
biomarkers for oxidative stress (plasma, MDA, TEAC)
and antioxidant status (plasma ascorbate, urate)
remained unaffected by cocoa flavanol ingestion. The
daily consumption of flavanol-rich cocoa has the
potential to reverse endothelial dysfunction in a
sustained and dose-dependent manner.
There has been considerable work on the relationships
between nutrition and the immune response,
particularly on studies that have focused on adaptive
responses. There is increasing recognition of the
importance of innate immunity in host protection and
initiation of cytokine networks. In this study, we
examined the effect of select cocoa flavanols and
procyanidins on innate responses in vitro. Peripheral
blood mono-nuclear cells (PBMCs), as well as purified
monocytes and CD4 and CD8 T cells, were isolated from
healthy volunteers and cultured in the presence of
cocoa flavanol fractions that differ from another by
the degree of flavanol polymerization: short-chain
flavanol fraction (SCFF), monomers to pentamers; and
long-chain flavanol fraction (LCFF), hexamers to
decamers. Parallel investigations were also done with
highly purified flavanol monomers and procyanidin
dimers. The isolated cells were then challenged with
lipopolysaccharide (LPS) with quantitation of
activation using CD69 and CD83 expression and analysis
of secreted tumor necrosis factor (TNF)-alpha,
interleukin (IL)-1beta, IL-6, IL-10, and granulocyte
macrophage colony-stimulating factor (GM-CSF). The
chain length of flavanol fractions had a significant
effect on cytokine release from both unstimulated and
LPS-stimulated PBMCs. For example, there was a
striking increase of LPS-induced synthesis of
IL-1beta, IL-6, IL-10, and TNF-alpha in the presence
of LCFF. LCFF and SCFF, in the absence of LPS,
stimulated the production of GM-CSF. In addition, LCFF
and SCFF increased expression of the B cell markers
CD69 and CD83. There were also unique differential
responses in the mononuclear cell populations studied.
We conclude that the oligomers are potent stimulators
of both the innate immune system and early events in
adaptive immunity.
BACKGROUND: Long term cocoa ingestion leads to an
increased resistance against UV-induced erythema and a
lowered transepidermal water loss. AIM OF THE STUDY:
To investigate the acute effects of a single dose of
cocoa rich in flavanols on dermal microcirculation.
METHODS: In a crossover design study, 10 healthy women
ingested a cocoa drink (100 ml) with high (329 mg) or
low (27 mg) content of flavanols. The major flavanol
monomer in both drinks was epicatechin, 61 mg in the
high flavanol, and 6.6 mg in the low flavanol product
per 100 ml. Dermal blood flow and oxygen saturation of
hemoglobin were examined by laser Doppler flowmetry
and spectroscopically at 1 mm skin depth at t = 0, 1,
2, 4, and 6 h. At the same time points, plasma levels
of total epicatechin (free compound plus conjugates)
were measured by means of HPLC. RESULTS: Subsequent to
the intake of high flavanol cocoa, dermal blood flow
was significantly increased by 1.7-fold at t = 2 h and
oxygen saturation was elevated 1.8-fold. No
statistically significant changes were found upon
intake of low flavanol cocoa. Maximum plasma levels of
total epicatechin were observed 1 h after ingestion of
the high flavanol cocoa drink, 11.6 +/- 7.4 nmol/l at
baseline, and 62.9 +/- 35.8 nmol/l at 1 h. No change
of total epicatechin was found in the low flavanol
group. CONCLUSION: Flavanol-rich cocoa consumption
acutely increases dermal blood flow and oxygen
saturation.
Mark
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