Arginine, Pycnogenol and Erectile Dysfunction and Impotence
L-Arginine and Pycnogenol. Both
L-Arginine and Pycnogenol have good track records in the research for increasing
endothelial Nitric Oxide, which is the prime chemical involved in erections.
 Several studies have shown that supplemental L-Arginine increases
blood flow, even in healthy individuals. 
Furthermore, a well-done study shows that these can significantly cure and often
cure erectile dysfunction (impotence).
Oxide relaxes the veins of the penis allowing blood to flow in which obviously is
critical for an erection. (Viagra, Cialis and Levitra work on Nitric Oxide for example.) By
the way, you bodybuilders may be interested to know that Arginine is used to
make creatine as well.
NOTE: Not all studies have shown L-Arginine
in a positive light as far as being a promoter of Nitric Oxide. For example,
one study of healthy males showed no increased blood flow from 20
g/day of Arginine, which is a very large dosage .
disappointing results were found in patients in
patients with heart failure as well.  It is much more safe
and effective to
Boost Nitric Oxide Through Food and Drink.
Pycnogenol is a Nitric Oxide producer or stimulator. (Several foods
are.) L-Arginine is the precursor for Nitric Oxide in the body and for Nitric
Oxide Synthase, the enzyme that crates Nitric Oxide, and thus can boost Nitric Oxide
indirectly in several ways.  The idea that some researchers had was that Arginine could
provide the building blocks for Nitric Oxide and then Pycnogenol would take that
substrate and pump out more Nitric Oxide. One study had already showed that
50 men given 5 g L-Arginine per day doubled their urinary Nitric Oxide secretion.
 However, that's quite a bit of L-Arginine and so, I presume, the researchers
wanted to find a safer approach using Pycnogenol.
Pycnogenol is a Nitric Oxide producer in its own right. Arginine also boosts Nitric Oxide directly by being its precursor. One study showed that
50 men given 5 g L-Arginine per day doubled their urinary Nitric Oxide secretion.
 If you put the two together, reasoned one set of researchers, you’ve got a potentially
powerful solution to erectile dysfunction. And they reasoned correctly:
study of men with erectile dysfunction  showed very significant improvement in the ability to achieve an erection though a combination of 1.7 G L-Arg per day along
side 2X40 mg doses of Pycnogenol.
Steven Lamm, in his book
The Hardness Factor,
recommends a dose of L-Arginine of 3 g per day.
He chose this value because it would
approximately double what a male would consume through an average diet. (By the way, L-Arginine also increases sperm counts for those of you
struggling with pregnancy-related issues.)
Need to boost your Nitric Oxide naturally through food, drink and supplements? Check out Lee Myer's book here:
The Peak Erectile Strength Diet
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Italian researchers found that L-Arginine supplements actually helped blood sugar
metabolism and insulin sensitivity of obese, Type II diabetics. 
Of course, elevated blood sugar and insulin sensitivity is not just a problem of
obese diabetics but is the curse of many on a Western diet . Those on a
Western Diet also need the increased Nitric Oxide output in to help protect
their cardiovascular system AND erections.
You may also be familiar with a nice side benefit of L-Arginine: the
stimulation of growth hormone release.
But keep in mind that this only occurs when ingesting fairly high levels of L-Arginine. Syracuse researchers found that 7 g/day of growth hormone
increased growth hormone response.  And when coupled with weight lifting, an
even greater growth hormone response was achieved. Other studies list doses (to
achieve growth hormone output) between 8-12 g/day.
Again, I recommend caution with
such high doses. (See Side Effects below.)
Caffeine and L-Arginine
Caffeine and L-Arginine can act synergesitcally. This is because one reason
that we experience decreased Nitric Oxide output is because of an increase in
our "arginase pathway". What happens is that more our precious arginine is
funneled through arginase instead of being available to make Nitric Oxide for
your heart and penis.
What is a good way to decrease arginase activity? Well, one recent animal
study shows that caffeine does just that. Rats given a relatively small
dose had significantly reduced arginase  and one reason is probably
caffeine's increase in Cyclic AMP. This is just one study and is on
animals, but it probably explains why caffeine and L-Arginine can be a winning
combination. (Be careful not to have so much caffeine that it disturbs
I should also point out that anther recent study actually investigated arginase
inhibitors - there are drugs that will, like caffeine, inhibit arginase
expression - for sexual disorders.  Their conclusion? The study stated, "Accordingly, arginase inhibition can enhance NO-dependent physiological
processes, such as the smooth muscle relaxation required for sexual arousal:
administration of arginase inhibitors in vitro and in vivo enhances erectile
function and engorgement in the male and female genitalia. Therefore, arginase
is a potential therapeutic target for the treatment of sexual arousal disorders
in men and women". But this is cutting edge and has not yet resulted in
any actual treatment protocols.
However, you can get in on the ground floor with a combination
of pycnogenol (or other dietary Nitric Oxide boosters specified in my
Erectile Dysfunction Dietary Program), L-Arginine and caffeine. This is definitely
a winning combination.
Arginine and Weight Loss:
One recent animal study showed that Arginine may actually help with weight loss
and fat reduction. Animals fed L-Arginine had substantial weight
reductions over controls.  Granted, these were obese rats due to
overfeeding, but the point is that the Arginine helped them significantly
regardless as to whether they were eating a low fat or high fat diet. It
is definitely involved in blood sugar and insulin: it is glycogenic,
meaning it can be converted to glucose, or blood sugar and deficiencies can lead
to decreases in insulin.
Side Effects of L-Arginine:
Side Effect #1: I do not advise taking more than 2-3 g of L-Arginine
per day. Arginine can be converted in the body to Nitric Oxide,
which is a good thing, or to a second amino acid, L-Ornithine. Unfortunately,
L-Ornithine can help cancerous tumors grow. In addition, L-Arginine
can increase body ammonium levels which could potentially lead to increased Herpes
Again, play it safe and stick to L-Arginine levels that would be approximated by
a reasonable diet, i.e. 2-3 g/day. NOTE: Arginine can also boost the
immune system because it stimulates the thymus, a gland in your upper chest that
pumps out an important leukocyte for immunity.
Side Effect #2: If you have a heart condition, work with
your doctor before taking Arginine
or any supplement. One Journal of the AMA study [Vol. 295 No. 1, January 4, 2006]
reported that researchers gave 153 heart-attack survivors 9 g daily of L-Arginine.
Six participants on the L-Arginine died, pushing the researchers to actually halt
the study. Keep in mind that thousands and thousands of people have taken L-Arginine
without incident and that the study individuals had heart problems. Also, keep in
mind that this is a fairly high dosage of L-Arginine: I would recommend more
in the 2-3 g range. Regardless, it underscores the need to get the advice
of a medical professional.
Side Effect #3: L-Arginine taken at higher doses is alleged
to cause higher body ammonia levels leading to potential herpes and/or shingles outbreaks.
This appears to be ameliorated through the consumption of cruciferous vegetables
such as brocolli, cauliflower and cabbage which are high in indole-3-carbinol
(I3C). I3C interferes with the way that shingles and herpes viruses
Arginine and Diet
You can get a respectable amount of L-Arginine through your diet. Of
course, your body manufactures L-Arginine as well, but supplemental or dietary
Arginine is what will produce a clinical effect. Good plant source of
dietary Arginine include peanuts, almonds, sunflower seeds, walnuts, hazelnuts -
almost any kind of nut - as well as lentils, kidney beans and soybeans.
Several animal products, including fish, chicken, shrimp and egg yolks also have
substantial L-Arginine. In addition, it is in most meats and dairy
products as well.
Also, if you do decide to take L-Arginine supplementally, it is probably more
effective on an empty stomach. It can compete with other dietary
components, such as L-Lysine, and so is probably better absorbed just by itself.
Arginine - Other Advantages
L-Arginine is another chemical that is used in many of the body's processes.
L-Arginine is a component of collagen and thus is important in skin maintenance
and repair. I also document in my
How to Improve Male Fertility link the
role that Arginine can play in improving our ability to achieve pregnancy.
(Seminal fluid contains a lot of Arginine for starters and, of course, it can
help with erections and some say libido as well.) Also, a recent study
showed some cardiovascular beneftis as well.  Men with high cholesterol were
given 12 g/day, which is a lot in my opinion, resulting in a slightly decreased
blood pressure and significantly decreased homocysteine, a leading heart disease
risk factor. Another study gave 6 g/day of L-Arginine and also found a
decrease in blood pressure and an increase in blood flow. 
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