This
webpage is an excerpt from my book, Cardiovascular Efficiency vs Nutritional Deficiency, available through the
International Foundation for Health and Nutrition in San Diego, California
(858)-488-2533. While it is rather technical, the caliber of my patients seems
to demand some proof in the pudding. It is not complete by any means, but I
think it will give you a broader understanding of this mis-understood
topic…
******************
Nearly every discussion of cardiovascular health includes
the cholesterol status, but it is equally important to also consider
triglycerides, triglyceride:HDL ratios, thyroid
function, insulin, lipid peroxides, fibrinogen, lipoprotein (a) levels, uric
acid levels, iron studies, plasma homocysteine, calcium:phosphorus
ratios, testosterone level, etc. All of these biochemicals are related to
cardiovascular disease either as markers of another underlying disturbance or
along the same pathways of cholesterol metabolism.
Cholesterol
is hard and waxy and either ingested or manufactured from the breakdown of
sugars, fats, or proteins.
- Cholesterol is
essential to the proper function and structure of cell membranes. In fact,
cholesterol keeps membranes from falling apart. This property of
cholesterol is so vital that each cell has the capability of manufacturing
cholesterol if necessary.
- The liver,
adrenals, sex glands, intestines, and even the placenta manufacture
cholesterol. Cholesterol is a component of steroid hormones, including pregnenolone,
estrogens, progesterone, testosterone, vitamin D, and the hormones we
associate with adrenal function such as DHEA, cortisol, aldosterone, etc.
- Bile acids are
derived from cholesterol and serve as an important part of fat digestion,
absorption, and excretion. Later in this text, the paramount importance of
fat absorption and utilization will be discussed.
- Cholesterol,
secreted by glands in the skin, serve as one of
the body's protective barriers to dehydration and infection.
The
concern about cholesterol was largely fueled by the Framingham Study and others
that provided strong evidence that when large populations are observed, persons
with higher than average serum total cholesterol have a higher incidence
of coronary artery disease (CAD). The Framingham Study was an epidemiological
study and not an investigation of cause and effect, it merely reported the
association between total serum cholesterol levels and CAD. Isadore
Rosenfeld, M.D. used a great analogy with fever and pneumonia. When you have
pneumonia your temperature goes up; but the fever doesn’t cause the pneumonia,
and lowering it won’t cure the infection. The actual cause of CAD is thought to
be initiated when there is an injury to the arterial wall, which results in
calcium deposition into the arterial wall. Bacteria or other infectious agents
are being looked at as part of the culprits as causative factors in initiating
injury to the arterial wall. Cholesterol is then attracted to this ‘rough’ site
on the blood vessel wall in an attempt to heal the wall so that blood will flow
smoothly over the injured area. No research has ever shown cholesterol building
up on a healthy blood vessel and slowly clogging it just as a sewage pipe might
over time. Cholesterol itself is not the cause of CAD. The blood cholesterol is
rather only a reflection of other metabolic imbalances in the vast majority of
cases. (There are genetic hyperlipoproteinemias in
which excessive cholesterol is considered the primary factor). This has been
the observation in Southern Europe where
elevated cholesterol levels do not correlate at all with coronary artery
disease. This phenomenon can be explained in part by understanding that there
are several types of cholesterol. To be precise we should use the term
cholesterols when we are speaking generically about total cholesterol.
In
contrast to large population studies, the majority of heart attacks do not
occur in high-risk individuals based on their total serum cholesterol (D. Mark Hegsted, Ph.D. Professor of Nutrition Emeritus at Harvard).
In a World Health Organization report, in the U.S., about one half of heart
attacks occur in individuals with serum cholesterol below 240 mg%. Dr. William
Taylor of Harvard further points out that "for many people with
cholesterol levels elevated into the high risk range, cholesterol reduction by
itself only adds on the average of about three weeks to total life span."
Of course, Dr. Taylor is only talking about using a medication or a dietary
program designed primarily to adjust the cholesterol level, and not the
underlying mechanism that raised the cholesterol in the first place.
Laboratory
reports often mention two main types of cholesterol, the HDL cholesterol (often
termed the "good" cholesterol) and LDL cholesterol (often mis-named the "bad" one. A more precise term would be “susceptible”
cholesterol). A third cholesterol type is also mentioned, the VLDL, which we will not mention again. Let's focus on the
"bad" cholesterol, the LDL cholesterol, which is composed of two
general sub-types; a large LDL and a smaller, denser LDL. Even if the total LDL
is lowered, the important fraction is actually the small LDL, which is more
easily oxidized into a potentially atherogenic
particle than its larger, more buoyant counterpart. "Statins"
were ineffective in reducing the small LDL particles according to Art Charles,
M.D. at the University of California at Irvine
in his work involving Insulin-dependent diabetics. Unfortunately, determining
the size distribution of LDL is not readily available, and thus checking the
total LDL levels is only half the story.
Most
everyone agrees that a markedly elevated LDL cholesterol
and total cholesterol should be lowered and a low HDL should be raised.
Although the present class of medications called "statins"
(Baycol ®, Lescol ®,
Lipitor®, Mevacor®, Pravachol®,
Zocor®, etc) does lower cholesterol and LDL, they do so by inhibiting the
enzyme that participates in the synthesis of cholesterol, HMG-CoA
reductase. This enzyme also participates in the production of coenzyme Q10.
Coenzyme Q10 is critical in energy production. Of course, energy production is
what life is all about. HMG-CoA reductase inhibitors
have also been associated with carcinogenicity, liver toxicity, stomach ulcers,
and breakdown of muscle. It should be noted that the active ingredient in Mevacor is also found in a commonly
used red rice yeast from China
that has been sold over-the-counter as a natural alternative for high
cholesterol. For this reason, herbal remedies should be used with the same respect
and caution as pharmaceutical agents.
Recently,
there have been preliminary observations that one the components in Mevacor and Zocor have anti-cancer effects in certain types
of tumors. The data suggests that it is a metabolite in these drugs that is the
active component in this regard. Further studies are necessary to determine if
these effects are clinically relevant and even related to the
cholesterol-lowering activity. It is important to recall one of the major
functions of LDL cholesterol, that is transport fatty
acids into your cells. Anything that
reduces fatty acid levels in the cell membranes has the potential to reduce
cellular aerobic metabolism (see my webpage on cancer!). Could it be that if you eat healthfully with
adequate amounts of essential fatty acids that the statins
actually promote cancer while the individual who eats poorly by consuming
trans-fatty acids (partially hydrogenated) is protected from cancer because
these anaerobic-promoting fats are not delivered to the cell? Nevertheless, there a several peer-reviewed
studies showing a significant increase in cancer incidence in subjects using statins. Most
studies showing the increase were longer term studies as would be expected for
carcinogenesis to be evident.
Another
class of cholesterol-reducing agents, sometimes called the "fibrates" (Atromid-S® and Tricor® are current examples) are also used but have toxic
effects on the liver. These to seem to have some proclivity to increase cancer
incidence as well.
In
a provocative article in Circulation (Aug 1997), rabbits were fed a diet that
is known to produce atherosclerosis. In addition, the rabbits were given either
extra L-arginine (an amino acid) or Mevacor (one of
the statin drugs). Several of the results and conclusions were surprising.
Carotid blood vessel plaquing was blocked in the
group with additional L-Arginine but not by Mevacor. Aortic thickening was reduced by L-Arginine
better than Mevacor. In addition, superoxide
radical generation in the atherosclerotic wall was reduced with L-Arginine and
increased with Mevacor. When L-arginine is infused
directly into the coronary arteries, endothelium dependent vasodilation
of the coronary microcirculation occurs indicating a rapid and direct effect
(Circulation 1996;94(2):130-4). In other words,
L-arginine seemed to be more effective than Mevacor
not only in reducing the production of atherosclerosis, but also helped the
smaller blood vessels.
If
we assume blood lipid (fats) status are associated with some risk of
cardiovascular disease. The question is which lipids are the important markers,
and even more important what should we do about them. In an 18 year follow-up
of 740 patients, the risk factors for having a CAD event were diabetes
mellitus, triglycerides >100mg%, and HDL Cholesterol <35mg%. In fact,
there was a significant reduction in survival from CAD events when the
triglycerides level was >100mg%. Total cholesterol and LDL didn’t
even show a statistically significant relationship (J American College Card;
May 1998)! Another study published in Circulation (October 1997) compared
triglycerides (TG), TG:HDL
ratios, cholesterol ratios, and LDL:HDL ratios for
the association with heart disease in 680 adults. By far the most important
association was the TG:HDL
ratio. At the XIV
International Symposium on Atherosclerosis (ISA 2006), evidence was presented
from clinical trials that assessing the levels of apolipoprotein (apo) B, a
constituent of atherogenic lipoproteins; apo A-I, a
component of antiatherogenic high-density lipoprotein
(HDL) cholesterol; and the apo B/A-I ratio provides better prediction of future
cardiovascular events than measuring serum low-density lipoprotein
(LDL)-cholesterol levels. In 2004, the global INTERHEART
study (Lancet 2004; 364:937-52) of risk factors for acute myocardial
infarction (MI) in 52 countries concluded that "the apo B/A-I ratio was
the most important risk factor in all geographic regions." In addition data
from the long-term follow-up of a prospective trial and analyses of major
clinical trials of lipid-lowering therapy show that the predictive power of the
apo B/A-I ratio is superior to, and cannot be improved by adding, any other
lipid parameter or ratio. In another study published by Arteriosclerosis, Thrombosis, and Vascular Biology. 2006 (26:406-10), the
apo AI /B ratio was related to the Metabolic Syndrome (discussed elsewhere), as
well as to a direct measurement of insulin resistance.
Taking
a closer look at triglycerides, the common reported causes of elevated
triglycerides are: familial, obesity, physical inactivity, insulin
excess/resistance (Diabetes mellitus; inactivity; excess fats, sugar, alcohol,
and calories), drugs (ß-blockers, corticosteroids, estrogens, thiazide diuretics, etc.), liver dysfunction (alcohol,
viral hepatitis, endotoxins, etc.), toxic exposures
(heavy metals, chlorinated hydrocarbons), and omega-3 fatty acid deficiency.
One would assume that exercise, eating less carbohydrates
and avoiding excesses of any foods, and ensuring that you have an adequate
amount of the proper oils should lower the triglyceride to a healthier level.
The omega-3 fatty acids are usually derived from fish…
As
with all things in life, there must be balance. Lowering cholesterol too
aggressively (usually will ONLY occur with synthetically derived therapies,
extremely imbalanced diets, or in artificial circumstances) or having too low a
total cholesterol is also undesirable. In fact, as you may come to agree,
elevated cholesterol is the lesser of the evils compared with a low cholesterol
level. The connection of low cholesterol to cancer was first recognized in 1971
by Pearce and Dayton
when they observed that a diet high in poly-unsaturated fats was associated
with a cholesterol lowering effect and an offsetting rise in cancer (Lancet
1971;464-7)! Ibrahim and
McNamara showed that the PUFA did not lower
cholesterol production or increase its secretion, but rather caused cholesterol
to accumulate in the tissue and thus appear reduced in the blood (Biochem et Biophys Acta 1988;963:109-18). Using data
from 6 different studies from all over the world, the total cholesterol level
that correlated with an increase in cancer prevalence is below 190 mg% and an even
higher risk when below 160mg%. The cancers found were lung, colon (in
non-smokers), breast (beyond radiographic mammary dysplasia), prostate, and
leukemia. (i.e. Nathan Pritikin).
There is an increase in mental illness inversely related to cholesterol levels
as well. There was a protective effect for cancer mortality with cholesterol of
greater than 240mg%. The studies suggest an optimal range of cholesterol is
180-239mg%. This is a range of 60 mg/dl. One might attempt to get into the
lower end of this range with heart disease patients and the higher end with
cancer patients.
Levels < 180 mg/dl are associated with a
§
200%
increase in cerebrovascular accidents (strokes)
§
300%
increase in liver carcinomas
§
200%
increase in lung disease
§
200%
increase in depression and (suicides)
§
200%
increase in addictive behavior
The
conclusion from a study published in the American Geriatrics Society (2005; 53:
219) was that low cholesterol level is a robust predictor of mortality in the nondemented elderly and may be a surrogate of frailty or subclinical disease.
After the age of 50, the lower your cholesterol level is, the lower your
life expectancy. Ways to lower
cholesterol are important to recognize, but more importantly, why the
cholesterol is elevated and how to address the underlying cause must be
considered. Here are some rather technical thoughts on how to balance
cholesterol metabolism.
Rather
than simply treat the lab numbers, when confronted with an elevated cholesterol
or LDL cholesterol level, your investigation must begin with "why?"
J. Yudkin et al (Brit Med J 1980; 281:1396)
demonstrated that increased sucrose intake significantly decreases HDL
cholesterol, and Reiser et al (Am J Clin Nutr 1979; 32:1659) showed
an increase in dietary sucrose increases total serum cholesterol. Using fructose
instead of sugar, as is the fad among food and health food marketers trying to
exploit the misconception that fruit sugar is better than other forms of
sugars, was shown by Reiser (Science News 3/28/1988;
133: 196) to elevate LDL, cholesterol, triglycerides, and uric acid. After 5
weeks of a diet with 20% of total calories from fructose, the cholesterol
increased 11% and the triglycerides jumped 56%. The national average
consumption of fructose at the time of study was 10%. The percentage is
probably higher now with the large push by marketers and the availability of
high fructose corn syrup and white grape juice. The excess of dietary
carbohydrates contributes to elevated cholesterol levels due in large part by
the influence of insulin. In fact, when all the data is considered, the
strongest evidence implicating dietary influences on elevated cholesterol
levels involves refined carbohydrates. In your mind, refined carbohydrates
should equate to any "processed or simple" carbohydrate ranging from
white flour to white table sugar. The
reason for this is explained by A. Guyton in his Textbook of Medical
Physiology, “When the quantity of glucose entering the liver cells is more
than can be stored as glycogen or can be used for local hepatocyte
metabolism, insulin promotes the conversion of all this excess glucose into
fatty acids. These fatty acids are
subsequently packaged as triglycerides in very-low density lipoproteins and
transported in that form by way of the blood to the adipose tissue and
deposited as fat.”
The
sugar issue is not that clear cut, however. Cardiovascular mortality rates are
twice as high in patients showing reduced glucose tolerance (Lancet 1980;
1:1973-6) and 2 - 6 times higher in overt diabetics (Adv Metab
Disorder 1970 [suppl]; 1:395). Sugar intake alone may
not be the only culprit. The inability to manage glucose (either eaten or
produced by the body) also is relevant.
Cholesterol
can only be ingested from animal sources such as eggs, meat, dairy
products, fish, and shellfish. Plants do not contain cholesterol. It is
estimated that half of cholesterol eaten enters the body while the other half
passes through. Normally, the more cholesterol we absorb, the less our bodies
make (Lehninger’s Biochemistry). According to Guyton’s
Textbook of Medical Physiology, “An increase in the amount of
cholesterol ingested each day increases the plasma concentration of slightly. However,
when cholesterol is ingested, the rising concentration of cholesterol inhibits
the most essential enzyme for endogenous synthesis of cholesterol,
3-hydroxy-3-methylglutaryl CoA reductase, thus providing
an intrinsic feedback control system to prevent an excessive increase in plasma
cholesterol concentration. As a result,
plasma cholesterol concentration usually is not changed upward or downward more
than ± 15 percent by altering the amount of
cholesterol in the diet, although the response of individuals differs markedly.”
To
understand how to manage cholesterol better, it is important to realize
cholesterol is made from small 2-carbon fragments called acetates hooked end to
end. Through multiple steps the 27-carbon molecule of cholesterol is formed. How
the process occurs is complex and the important question is where do the 2-carbon acetate fragments come from, and what
promotes their linkage together to form cholesterol? When fatty acids are
broken down for energy, they are broken down into acetate fragments. When
sugars and starches are broken down for energy, they produce acetate. Proteins
are generally broken down into amino acids, but with extreme protein
consumption or during certain disease states, certain proteins can be broken
down into acetate. Excess acetates can come from eating too many non-essential fatty
acids, trans-fatty acids, and saturated fats, and refined carbohydrates (via
insulin and other agents). This "pressures" the body to form
cholesterol. In other words, cholesterol is formed from excess calories - most
often this is from carbohydrates and fats.
Be
sure not to make the common error of considering all saturated and all
unsaturated fats as having equal properties. As you will see from the
discussion below, the structure of unsaturated fats have a profound influence
on their biological effect. With regard to the saturated fats, which are
fats that do not contain any double bonds, there are three important
considerations. The first is the length of their carbon backbone, the second is
if they have been artificially desaturated through a
process called hydrogenation, and the third is what components are associated
with the fat. Length: fatty acids with short chains (SCFA) have between 4 - 14
carbon atoms in length) and are the principal source of energy for the colon.
They are easily absorbed into the colonic mucosa and affect nutrient absorption
and digestion, which in turn impacts the cardiovascular system. One food with a
high amount of SCFAs is butter. Fatty acids with a
medium chain (MCT) are easily absorbed and provide an
important energy source. One study shows combining coconut MCTs
with omega-3 fish oils enhanced the cardioprotective
effect of the omega-3 fatty acids. This study supports the observations made
over and over again about the importance of the fact that saturated fat intake
is essential for normal hormone production.
In
a study of individuals older than 84 years, the consumption of nuts 5 times per
week had a relative risk of death from cardiovascular disease of 82% compared
to those that did not consume nuts (Arch Inter Med 1997;157:2249-58).
In a study published in JAMA (1997;278:2145-50),
there was an inverse association of strokes in men with dietary fat intake. In
other words, a low fat intake was associated with a greater risk of ischemic
stroke. Lowering dietary fat to 30% reduced LDL, but lowering dietary fat to
<22% increased triglycerides and lowered HDL. None of the low fat diets was
associated with low body weight, blood sugar, insulin, or blood pressure.
Dietary
omega-3 fatty acid intake (1.5 grams/day) for two years was shown to
"modestly mitigate" the course of coronary atherosclerosis in 223
patients with angiographically proven coronary heart
disease (Annals of Internal Medicine 1999;130:554-62).
Peroxidation of lipids occurs when unsaturated fats are
exposed to oxygen and/or light; it is responsible not only for the
deterioration of fat (rancidity) but also for damaging tissue. This process may
play a prominent role in promoting cancer, atherosclerosis, inflammatory
diseases, autism, Parkinson’s disease, and aging. Lipid peroxidation occurs
only at unsaturated double bond sites and results in a continuous supply of
free radicals that can initiate further peroxidation. To control this effect,
food manufacturers use antioxidants such as synthetic propyl
gallate, butylated hydroxytoluene (BHT), and butylated hydroxyanisole (BHA) as food additives since they are strong antioxidants.
Because quality essential fatty acids are so fragile and yet absolutely
necessary, polyunsaturated oils should be purchased in small quantities, kept
cool and in the dark, and used rapidly to prevent lipid peroxidation. Keeping
the container in the refrigerator, tightly capped, in a light-proof container,
and with added natural vitamin E helps. Many natural whole foods containing
antioxidants such as red grapes are being exploited for this property.
Supplementing with whole complex E (which is naturally complexed
with selenium) helps combat peroxidation.
Hydrogenation, a process introduced in large scale in the 1930's
for making margarine and shortening, alters fatty acids to make them more
resistant to lipid peroxidation. In this process, an oil
with unsaturated fatty acids in their natural, all cis
configuration, are reacted at high temperatures and under pressure with
hydrogen gas in the presence of a metal catalyst (typically nickel).
Hydrogenation saturates the double bonds (it puts a hydrogen atom where there
was a reactive open site) so the fatty acid becomes saturated, hardens, and
becomes more resistant to lipid peroxidation. Hydrogenated oil makes potato
chips crisp and have a longer shelf life.
Unfortunately, the consumer ends up with fats and oils that are the nutritional
equivalent of other refined products — demineralized,
devitaminized, fiberless,
empty calories which cannot be properly digested or metabolized, and rob the
body of essential nutrients in doing so.
Partial
hydrogenation occurs when the above process is not brought to completion,
leaving fatty acids with a few unsaturated double bonds. However, partial
hydrogenation forms both trans and cis double bonds (saturated fats do not have cis and trans configurations), shifted double bonds,
fragments, etc. The process is random and so no one really knows all of the
resulting products. The reason processors partially hydrogenate unsaturated
oils is to prolong shelf life and keep partial liquidity of the fat. Read the
label on baked crackers, salad dressings, mayonnaise, hot chocolate, cereals,
breakfast bars, snacks, etc. and you’ll see the extent these oils are now used.
Trans fatty acids are produced when an
unsaturated fatty acid is exposed to high temperatures (which is why to
preserve the natural cis configuration,
cold-pressing of the vegetable oils are recommended). The slight difference in
the structure between a trans and cis bond has a dramatic effect on the shape and
function of the fatty acid. In nature, whether in animals or in plants, the
carbons on either side of the double bond are in the cis
conformation that results in a bend in the fatty acid chain. On the other hand,
the trans conformation results is a straighter and more elongated fatty
acid chain that can align closer together with other fatty acids, and therefore
is more solid and more sticky, which encourages deposition into arteries,
organs, and platelets. (Saturated fats are even stickier). For the same
reasons, trans fatty acids also get in the way
of cis fatty acid interactions with enzymes
and with the function and permeability of cell membranes (saturated fatty acids
do not). Trans fatty acids are useful only to
the body as energy-creating fuel and are broken down at a slower rate than cis fatty acids. Since trans
fatty acids are more stable than cis double
bonds, the chance of being converted into the more desirable cis configuration is unlikely. The main dietary
source of trans fatty acids is from partial
hydrogenation. Read a few labels from cereals, crackers, chips, snacks, instant
hot chocolate, salad dressing, etc. to see just how much partially hydrogenated
oil the average American consumes without suspecting it. There are no known
natural trans fatty acids. From the same study
that showed nuts reduce cardiovascular deaths to 82%, the regular consumption
of donuts not only increased the mortality from coronary heart disease 210% but
also death from any cause 140% compared to those that did not consume donuts
regularly (Arch Intern Med 1997;157:2249-58).
From
JAMA (Dec 24, 1997), 832 men were followed for up to
20 years. Those with a low fat and/or a low saturated fat intake had a much
higher incidence of stroke events. With higher and lower polyunsaturated fat
intake the effect was not as significant. The lesson here is that low fat is
detrimental which is not to say that high fat diets are necessarily beneficial.
Trans fatty acids can increase cholesterol
and triglyceride levels. In a study done at Harvard on 85,000 nurses, there was
a 50% greater incidence of heart disease among those women consuming the most trans fatty acids compared to those consuming the
least. The researchers concluded that "consumption of partially
hydrogenated vegetable oil may contribute to the occurrence of heart
disease." (Willett Lancet 1993) Recently the medical literature has been
more vocal about their concern over margarines, trans-fatty acids, partial
hydrogenation, etc.
Another
critical component of lipid metabolism warranting discussion is that of eicosanoids popularized by Barry Sears, Ph.D.
in his book, The Zone. Emmanuel Revici, M.D. provided the early conceptual
model for this entire field of fat metabolism. Eicosanoids
are a group of powerful chemical mediators that are derived from essential
fatty acids and control virtually every aspect of metabolism and physiology.
Prostaglandins, leukotrienes, and thromboxanes
are among the better described eicosanoids. As in
most biological systems, there is a balance among opposing eicosanoids
— the series 1 pathway components (generally associated with beneficial
activities) and the series 2 pathway components (generally associated with less
desirable activities such as inflammation). The biochemistry of those factors
that favor the series 1 eicosanoids over the series 2
eicosanoids have focused on the role of a critical
enzyme that directs fats down the series 2 pathway — the delta 5 desaturase enzyme. The enzyme is activated by insulin and
therefore excessive carbohydrates or carbohydrates with a high glycemic index,
aging, stress, viral infection, saturated fats, alcohol, and deficiencies of
vitamins and minerals. Strategies for controlling eicosanoids
into a favorable balance, called "The Zone," is the subject of Dr.
Sears book and another excellent text, Protein Power, by Michael Eades, M.D.
Any
discussion of fats cannot be complete without including carbohydrates, since
sugars and starches can be converted into fats. Refined carbohydrates
such as table sugar, fructose, syrups, puffed cereal grains, processed flours,
and honey provide an excellent source of energy, but if there is no activity or
exercise requiring this energy, then the body has an excess supply of glucose.
The capacity to rapidly raise blood sugar is called the glycemic index.
Normally, the body responds to high levels of glucose by stimulating the
pancreas to secrete insulin, which stimulates the metabolism of glucose into
fats for storage in fat tissue or in various organs. The fatty acids produced
from glucose metabolism are saturated and therefore can only serve as fuel. In
addition, high blood sugar inhibits the release of the essential fatty acid,
linoleic acid, from storage fat. This could exacerbate essential fatty acid
(EFA) deficiency despite having adequate stores of EFA. Complex unprocessed
starches, in contrast to refined sugars, are not as rapidly absorbed and do not
cause as dramatic a rise in glucose, the excess glucose. The glucose is
absorbed slowly and thus provides a relatively lower, and more prolonged level
of blood glucose energy; hence, a lower glycemic index. It is no surprise that a Denmark study
showed that "fasting serum insulin level is a very good predictor of the
development of CHD and CVD…"
According
to an article in the Journal of Cardiovascular Risk, June 1995, "All
dietary carbohydrates increase insulin levels. Excess carbohydrates cause elevated insulin levels…"
Angina
can be induced by hypoglycemia (Am Heart J 1943;26(2):147-163)
Insulin
promotes delta-5 desaturase activity lead to
increased pro-inflammatory eicosanoid production. Impaired sugar metabolism
stimulates adrenal exhaustion through blood sugar feedback attempts to increase
blood sugar lead to excess potassium, menopause & andropause,
etc.
Vegetables
in general lower insulin. Mung beans and other legumes (soybeans), Bitter gourd
(Momordica charantia),
Ivy gourd (Coccinia indica),
Brassica (cabbage, broccoli, cauliflower), green
leafy vegetables, omega-3 fatty acids (fish oils), anti-oxidants (vitamin E),
alpha-lipoic acid, possibly L-arginine (via NO pathway), chromium/glucose
tolerance factors, vanadium, and inositols (d-chiro inositol is important in
the construction of membrane proteoglycans that
maintain insulin sensitivity).
Syndrome
X is defined as "insulin resistance + hyperinsulinemia"
usually accompanied by elevated lipids, body weight, and blood pressure. The result is reduced cellular glucose
transport. Insulin affects gene expression by altering transcription factors
that affect triglyceride and cholesterol synthesis and degradation,
inflammatory cytokine release, shunting of estrogen to testosterone in women
(PCO). Hyperinsulinism contributes to
atherosclerosis, hypertension, hyperlipidemia, obesity, and diabetes.
Low
blood sugar levels lead to thyroid, anterior pituitary, adrenal cortex, and sex
hormones release. High blood sugar levels lead to insulin, posterior pituitary,
and sex hormone release.
As
a result of the Page Food Plan (dominated by protein and vegetables), which is
found under my web pages for food programs, the avoidance of sugar based on the
reasons above, one will quickly realize that the intake of protein necessarily
goes up. This has raised concerns about over-consumption of protein and its
effect on osteoporosis, etc. The British Medical Journal (October 1997)
included a study of 3600 Britons over a seven-year period. The results show no
correlation between meat consumption and cancer. Fresh fruits and vegetables
intake as expected had a protective effect. The other concern with increased
protein intake has been with promoting osteoporosis due to the systemic
acidification that results from protein metabolism. The fact is that the
Framingham Osteoporosis Study carried out over a four year period found that
individuals with the lowest protein intake had increased rates of bone loss
compared to those with higher intakes. In this study, the women who had the
highest percentage protein intake had no bone loss at all during the study
period. Another study in Switzerland
showed the same findings - higher protein intake was associated with greater
bone density. A Chinese study of elderly females found lower bone mineral
densities in vegetarians than in omnivores. There was no difference between the
lactovegetarians and the vegetarians with regard to
bone mineral density. Concern over consistent protein intake as recommended by
Page contradicts these observations.
OTHER FACTORS INVOLVED IN CHOLESTEROL AND LIPID METABOLISM
Steroid
hormones play an important role in cholesterol metabolism. After all,
cholesterol is a precursor to steroid hormones, including progesterone,
cortisol, estrogen, and testosterone. In Denmark, testosterone has
been used as a cholesterol-lowering agent for decades. They report the average
reduction in serum cholesterol after testosterone initiation in males is about
25%. A 1972 World Health Organization (WHO) symposium also provided evidence
that testosterone had cholesterol-lowering effects as well as increased clot
dissolution, and reduced the adhesiveness of platelets (by reducing the amount
of the pro-aggregation effect of ADP). Testosterone also induced suppression of
lipoprotein (a) levels (Marcovina SM in
Atherosclerosis 1996; 122: 89-95). These are all traditional parameters of
heart disease risk. Confirming the association between testosterone and heart
disease, Gerald Phillips, M.D. at Columbia
University Medical
School, showed that men
with the lower levels of testosterone had greater x-ray evidence of coronary
artery blockage. Maurice A. Lesser, M.D. injected testosterone to 100 patients
during an angina attack with "moderate to marked" improvement in 91%.
Testosterone
shifts metabolism from an anaerobic state to an aerobic one by increasing the
activity of enzymes in the Krebs cycle, which increases the level of ATP
relative to ADP, which affords the changes mentioned above as well as a variety
of other metabolic effects. Testosterone also balances glucose homeostasis by
antagonizing glucocorticoids and insulin. It has also been shown "to have
a direct effect on reducing blood sugar," in addition to lowering the
insulin requirements of diabetics and improving insulin resistance (J New Drugs
1965; 5: 108-224). Testosterone therapy has been useful for a variety of
degenerative conditions. Clearly, the notion that testosterone is merely a sex
hormone is to discount the profound effects it has on metabolism – rather it
should be considered an anabolic steroid in both males and females.
Testosterone also stimulates protein synthesis and decreases protein breakdown
leading to improved nitrogen balance. Some common clinical findings with
testosterone insufficiency are fatigue, reduced muscle energy, decreased
secondary sex characteristics, reduced temperature, reduced blood pressure,
cold sweaty hands, frequent/excessive urination, anemia, and compensatory
prostatic hypertrophy. The blood chemistry may show low phosphorus.
Another
factor involved in the balancing role of testosterone is its relationship to
saturated fat intake. In a study done in Finland, a diet containing only 25%
saturated fat decreased testosterone levels by 15%. The same effect occurred
when the ratio of polyunsaturated fats was increased compared to saturated
fats.
"Observational
studies have consistently shown that estrogen replacement therapy (ERT) is associated with lower overall mortality rates. The
effects on deaths due to coronary artery disease (CHD)
are striking: a pooled relative risk (RR) of 63%…" (Arch Intern Med 1997;157: 2181-7). However, women who use estrogen were more likely
to have healthy habits and characteristics such as not smoking, less
overweight, etc. Again, the cause and effect remains uncertain. According to
Joseph Collin’s 1999 book on endocrine function, estrogen has powerful
anti-oxidant effects.
Estrogen
has several other effects related to cardiovascular efficiency including
lowering LDL levels, increasing HDL levels, decreasing Lp(a) levels, affecting
endothelin-1, decreasing homocysteine levels and enhancing the effects of B-6,
B-12, and folic acid supplementation, decreasing the risk of hyperinsulinemia, and possibly lowering fibrinogen levels
and platelet aggregation.
Conventional
care for those women with a uterus and who take estrogen in any form, progesterone
are considered mandatory to offset estrogen’s uterine cancer-promoting effects.
The most commonly used form of progesterone is the synthetic derivative,
methoxyprogesterone (MPA
for short), Provera®. Unfortunately, a study published in March 1997 Nature
Medicine showed that "moderate levels of MPA
interfere with the protective effects of estradiol (E2) against
coronary reactivity and vasospasm…" This is not to say that progesterone
itself is detrimental. This distinction between natural progesterone and
synthetic progestins like Provera can not be overemphasized.
Excess
cortisol, on the other hand, not only raises blood lipids and
cholesterol, but also promotes the breakdown of protein. Tissue damage, high
blood sugar, sympathetic overflow, psychosocial stress leads to ACTH secretion
from the anterior pituitary and subsequent cortisol release from the adrenal
cortex. Testosterone counteracts this effect and normalizes carbohydrate
metabolism with reported marked improvement in pathological glucose tolerance.
Confirmation of this effect was recently published by IR
Reid in Osteoporosis International (1996;6(suppl 1):274) in 15 asthmatic men receiving long-term oral
steroid therapy. Bone density and muscle mass increased while body fat
declined. Testosterone also improves circulation with many reports of healing
of gangrene, etc. Since cardiac output is the ultimate determination of
workload capability of the heart (i.e. the primary marker of health), it is
worth understanding how the adult improves cardiac output when the demand
arises. We know cardiac output = stroke volume ´ heart rate. It is a fact that,
after the age of thirty, the maximal cardiac output declines. The primary way
the body stimulates greater output is to increase the heart rate through an
increase in the production of catecholamines. Testosterone tempers the
metabolic effect of increased catecholamines as well. Goodman and Gillman’s The
Pharmacologic Basis of Therapeutics (1980) reported "large or repeated
doses of catecholamines given to experimental animals lead to damage to arterial
wall and myocardium so severe as to cause the
appearance of necrotic areas indistinguishable in the heart from myocardial
infarcts." This tells us that atherosclerosis (and cholesterol) alone must
be appreciated for a rational approach to prevention and management of heart
disease. A high level of stress with greater overall production of
catecholamines and cortisol then must be offset by the balancing effect of
other hormones, of which testosterone is included. One could put this in
context of Revici’s dualism — the battle and balance
between insufficient oxidation and excessive oxidation. For our patients with
cortisol excess, either due to stress or medication, should we provide
testosterone? Perhaps this is why tranquilizing products such as Min-Chex (Standard
Process) that combine the minerals known to balance to autonomics
(catecholamines) with a source for testosterone production to balance the
hormones (cortisol) are so effective.
Another
adrenal hormone is DHEA, which can be useful addition in select
individuals. I would not recommend using it, however, without appropriate
medical guidance.
At
the meeting of the American
College for the
Advancement of Medicine in October 1997, a speaker reported that a persistently
low HDL suggested pituitary hypo-function. Other lab findings include an
increase in total cholesterol, low thyroid function tests, and a high
fibrinogen. At the 1996 American Academy
of Anti-Aging Medicine seminar in Las Vegas, Dr. Bengt-Ake reported that deficiency of growth hormone is apparently
associated with an increase in atherosclerosis and cardiovascular mortality.
Growth hormone has been considered an insulin antagonist. Adult growth hormone
deficiency may be characterized by sagging cheeks, deep and large wrinkles,
thin hair, lips, jaw bones, and skin, pseudogynecomastia,
an obese floppy belly, general muscle loss, fatigue, somnolence, lack of
self-assurance and esteem, anxiety, and low sociability. A mixture of arginine,
lysine, ornithine, and glutamine can be used to
induce growth hormone release. A variety of nutritional products have been
developed claiming to stimulate the pituitary to release growth hormone. Other
stimulators of growth hormone include hypoglycemia, exercise, sleep, estrogen, glucagon, and stress. Growth hormone itself, albeit in
minute amounts, can be purchased over-the-counter while recombinant growth
hormone is available through physicians as an injectable.
Insulin-like
Growth Factor-1 (IGF-1) is a derived from metabolism of Growth Hormone in the
liver. Effective Growth Hormone therapy elevates IGF-1 and IGF-1 itself has
been shown to decrease insulin levels, increase stroke volume, reduce vascular
resistance, and lower the filling pressures of the right and left heart.
In
continuing our discussion of hormones, thyroid hormones play a major
role in cholesterol metabolism and in atherosclerosis. Advocates of thyroid
hormone use report over 50 percent of Americans have low thyroid function, and
thyroid hormone levels within the normal range do not exclude a functional
deficiency/insufficiency. Gubner and Lange showed
hypothyroidism was associated with increased permeability of arteries and less
strength of capillaries. A significant percentage of individuals with
hypothyroidism have elevated cholesterol. In a study of 279 women, 12% with
cholesterol >240mg% had an elevated TSH (Amer J
Med; June 1998).
From
Melvin Page, DDS and other endocrinologists, it is known that blood calcium,
phosphorus, and cholesterol levels are controlled by the thyroid. With low
thyroid function, a relatively high calcium, low phosphorus and high
cholesterol is found. With elevated thyroid function, a relatively low calcium,
high phosphorus and low cholesterol is found. Of course there are other
influences on these levels beside thyroid, but with thyroid replacement, one
should be able to predict the resultant changes in calcium, phosphorus, and
cholesterol. The balance between calcium and phosphorus is among the most
important markers of biochemical homeostasis ever identified. For further
discussion, see later text.
Because
there is much confusion about thyroid hormone replacement or glandular support,
a brief review of thyroid metabolism is warranted. The thyroid gland secretes
thyroxine (T4) and a small amount of tri-iodothyronine (T3).
About 30% of T4 is de-iodinated to T3 and 40%
de-iodinated to reverse-T3 (rT3) in the periphery. Both T4 and T3
are metabolized in the liver by glucuronidation and sulfation. References state that T3 is about
three times* as active as T4 on target tissues and is the principal
regulator of thyroid action within the pituitary; rT3 has no
activity. (*There are some reports that T3 has nine times the
activity of T4). Dopamine and glucocorticoids reduce the pituitary’s
stimulus to secrete Thyroid Stimulating Hormone (TSH). It has been reported
that an excess of polyunsaturated oils, cabbage, soy foods, and improperly
prepared nuts and lentils, and beta-carotene suppress thyroid function.
Consider liver dysfunction or providing bioactive sulfur if thyroid support is
being taken and there is no clinical response. Thyroid function can be adjusted
with more than just hormones. To stimulate the thyroid, give phosphorus,
polyunsaturated FA (pulls iodine out of the gland), or provide sympathetic ANS
support. To depress the thyroid, give calcium, iodine (pharmacologic dose), or
provide parasympathetic ANS support. It is worth noting that there is often
confusion about the use of iodine with thyroid dysfunction. When there is insufficient
iodine, supplemental iodine provides support for the gland. When given in
excess, iodine suppresses the thyroid. One last caveat that many practitioners
have observed - whenever appropriate therapy of any kind or for any reason does
not provide a clinical response, consider thyroid support.
The
recent popularity of soy products has raised some concerns. Not only with
regard to its phytoestrogen content, but because it
will be marketed in high potency and in a processed form… This is not the forum
for a more thorough review but I'm going on records as having a great concern
about the intake of high amount of soy. The average daily consumption of soy
protein in the Orient is only a few milligrams.
Many
clinical trials have shown phosphatidylcholine reduces total cholesterol
and triglycerides by as much as 20-30% as well as a marked improvement in the
pathological lipoprotein patterns. Overall, the profile that has been
associated with the development of atherosclerosis improves including increases
in HDL cholesterol. Phosphatidylcholine also increases the mobilization of
cholesterol from pre-existing atheromas to the liver
for metabolism and ultimate excretion as bile acids. Improvements in
atherosclerotic vascular changes have been shown by several objective measures
as well as in reducing symptoms of angina pectoris, cerebral circulatory
disorders, and peripheral vascular disease. It is interesting to note that a
study showed choline conserved carnitine (J Clin Nutr 1996;63:904-10). It is nice
to get the confirmation that the balanced, comprehensive approach we’ve watched
in clinical practice work more successfully than a piecemeal fractionated
approach is supported in research. Lecithin is an excellent whole food complex
rich in phosphatidylcholine. Symptoms suggestive of a need for lecithin include
stiffness and bone spurs (phosphorus deficit), vasomotor disturbances (nerve
sheath integrity), gallbladder symptoms, and an intolerance to ingested fats
(complements bile in emulsification), lipomas and
elevated cholesterol (lipid transporter), and forgetfulness (memory occurs in
the acetylcholine-rich hippocampus).
Niacin has long been used for cardiovascular conditions,
especially involving lipid metabolism. The use of niacin for managing lipid
markers for cardiovascular disease is well established:
•
Reducing LDL and Total Cholesterol (5-25%)
•
Increasing HDL Cholesterol (15-35%)
•
Decreasing Triglycerides (20-50%)
•
Increase in Apolipoprotein A1
•
Decrease in Apolipoprotein B
•
Shift to larger (less atherogenic) LDL particles
•
Reduction in Lipoprotein (a)
It
also may help Raynaud’s Disease (excessive blood
vessel constriction due to cold and symptoms of intermittent claudication) due to insufficient blood supply to calf
muscles while walking. Niacin lowers VLDL formation
in the liver by activating phosphodiesterase and
inhibiting adenylate cyclase
which results in the reduction of cyclic AMP in fat cells which in turn reduces
the release of free fatty acids from fat cells. As a result, serum VLDL, LDL, triglycerides, phospholipids, and cholesterol
are decreased. Niacin also inhibits the formation of cholesterol from acetate
in the liver and appears to increase its breakdown as well. There is also
evidence lipoprotein A2 synthesis is reduced by niacin and that
niacin converts the smaller easily oxidized LDL into larger,
oxidation-resistant LDL particles.
Niacin
is part of the alcohol insoluble and heat labile fraction of vitamin B (named
the "G" complex that includes riboflavin, niacin, folic acid, PABA,
choline, inositol, and betaine).
As part of the "G" complex, it relaxes nerves and thereby acts as a
vasodilator, helping selected individuals with hypertension and smooth muscle
spasm without tone. According to Compiled Notes on Clinical Nutritional
Products by Wally H. Schmitt Jr., D.C. (1990) and Vitamin News
(1952), signs of "G" deficiency include:
According
to Robert Peshek, DDS the "G" fraction of
B-complex allows chloride to enter the cell, just as Valium does. Also raises
cholinesterase levels. In fact checking the level of rbc-cholinesterase
levels can be a guide to functional need for "G."
- Cardiovascular -
tachycardia, extra ventricular beats (PVC’s), angina pectoris, and
pre-myocardial infarction
- Psychological -
excessive worry, apprehension, moodiness, depression, suspicion
- Digestive –
insufficient stomach acid production and excess alkalinity, spastic gall
bladder
- Liver – cirrhosis
and loss of fat metabolism activity, deficient formation of Yakitron, a physiologic anti-histamine
- Neurological –
insufficient acetylcholine activity and cholinesterase activity (for
breaking down acetylcholine and for recycling choline), restless, jumpy,
or shaky legs, body or limb jerks upon falling asleep, can hear heartbeat
on pillow
- Skin and mucous
membranes – cheilosis (cracking at corners of
mouth), friable skin, especially on face and neck (when shaving), bright
red tongue tip, strawberry tongue (purple), loss of upper lip (thin upper
lip), irritated mucous membranes of the rectum, vagina, and conjunctiva
(frequent crying), excessive oil on face and nose, roughness, cracking and
exfoliation of the soles of the feet, and psoriasis
- Visual - burning
or itching of eyes, photophobia (sun sensitivity), blepharospasm
(eyelid spasms), blood shot eyes due to capillary engorgement, seeing only
parts of printed words (circumcorneal
injection), pallor of the temporal half of optic disc, transient ischemia
of retina - like looking through a fish bowl
- Endocrine –
excess estrogen and menstruation, cystic mastitis or gynecomastia,
premenstrual tension, and excessive adrenal function.
Note:
You may be wondering what the evidence for oral exam findings has to do with
the heart. The Medical Tribune ran an article in May 1999 correlating the
degree of gum disease with the degree of carotid artery plaque… I'm not making
this up.
Niacin
is also part of glucose tolerance factor (GTF) which is necessary for proper
glucose homeostasis, in part by acting in concert with insulin to improve the
body’s responsiveness to insulin. As a result, less insulin is required to
accomplish blood glucose regulation. Insulin reduces DHEA and increases the
production of the pro-inflammatory eicosanoids such
as arachidonic acid. Interestingly, the other part of
the vitamin B complex that is alcohol soluble, named the "B"
fraction, is combined with even a larger amount of niacin than the commercially
available "G" complex per tablet, and yet it has an opposite effect
in terms of nerve transmission, heart function, blood vessel tone, and other
metabolic functions. Wheat germ has been shown to bind irreversibly to the
insulin receptor and mimic its function, thereby creating an artificial insulin
effect. It is not known whether sprouting and/or de-fatting the wheat germ
changes this effect.
Niacin
is often sold as a timed-released or sustained release product to reduce the
flushing that is common when using the high dosage required to effect laboratory
benefit. Niacin is metabolized by two
pathways. One pathway is through conjugated
with Glycine resulting in Nicotinuric Acid (NUA). This results in most of the benefits of niacin mentioned
above but also produces the flushing. Niacin
can also be converted to niacinamide (NAM) and other
metabolites which are harmless at lower levels but can be potentially hepatotoxic at doses exceeding 1.5 grams per day. The goal of a sustained-release niacin
product is to release as much niacin via the first pathway (NUA)
without causing flushing, while fully releasing all the niacin before the
secondary pathway is able to form potentially hepatotoxic
metabolites. This may be alleviated by using a wax-matrix tablet to achieve a release
profile of 45% release within the first hour, 55% release by two hours, 85% in
the 3.5 hour, and 90% in 7 hours (www.orthomolecularproducts.com)
Pantethine has been shown in several studies to lower
cholesterol as well as inhibit the oxidation of LDL. In the cytoplasm of the
cell, pantethine promotes lipid formation at the
expense of cholesterol. In the mitochondria, pantethine
accelerates the beta-oxidation of fatty acids and enhances the metabolic flow
into the energy-producing Krebs cycle. During conditions of inadequate blood
supply, pantethine improves cellular energetics. Pantethine is a derivative of pantothenic acid (vitamin B5).
When
all is said and done, ideal cholesterol levels for adults is probably
180-200mg% with concern when it drops below 160mg% or when it is higher than
240mg%. For HDL (the "good" cholesterol), a level of >60 is worth
shooting for. A LDL (the "bad" cholesterol) should be less than
140mg%. Triglycerides should be <100mg%.
Apolipoprotein A1 / B ratio should be < 0.7 with an apolipoprotein B
level <84.