Download NEW! D-Chiro-Inositol: Enhances Insulin Function and Blood

January 2010
NEW! D-Chiro-Inositol: Enhances Insulin Function
and Blood Glucose Metabolism
Blood sugar dysregulation is one of the most
prevalent health problems of our time. Over
20 million people in the United States have
diabetes and approximately one in four have
metabolic syndrome, a cluster of symptoms
that includes insulin resistance, obesity,
dyslipidemia, and hypertension. Poor control
of blood sugar increases the risk for a variety
of serious health conditions including cardiovascular and peripheral vascular diseases,
neurological impairments, renal dysfunction,
damage to the retina and ocular lens, and
impaired ovarian function. Dietary and
lifestyle modifications can reduce the risk of
these complications. Nutritional intervention
with chromium, alpha-lipoic acid, and other
supplemental nutrients has also been shown
to be of significant benefit to supporting
blood glucose metabolism and insulin
activity, and providing protection against
glycation and oxidative free radicals.
Evidence also shows that dietary D-chiroinositol, a naturally-occurring form of
inositol that plays an important role in
mediating cellular sensitivity to insulin,
may be inadequate to meet the increased
physiological demands in some individuals.
Promotes Insulin Sensitivity
D-chiro-inositol (DCI) is a unique stereoisomeric form of inositol that plays a key
role in promoting insulin sensitivity in the
human body. By supporting insulin function,
DCI contributes to normal glucose and lipid
homeostasis. DCI functions as a component
of a membrane-bound, signal transduction
molecule that mediates the activity of
insulin. Upon exposure to insulin, this signal
transducer is hydrolyzed to yield a bioactive
DCI-containing inositol phosphoglycan
(DCI-IPG) which helps regulate the disposal of
glucose within cells. DCI-IPG activates both
glycogen synthase, which converts glucose
to glycogen for storage, and pyruvate
dehydrogenase, which facilitates oxidative
metabolism of glucose for energy. By
supporting normal intracellular glucose
metabolism, DCI plays an important role in
preventing hyperglycemia and its adverse
clinical consequences.
Research in both animals and humans
supports the use of supplemental DCI in
helping to normalize glucose metabolism.
In a rat model of diabetes, a single intragastric
dose of DCI was found to significantly lower
plasma glucose and insulin levels. In diabetic
mice, administration of a DCI-enriched
feed exerts a dose-dependent hypoglycemic
effect as measured by oral glucose tolerance
testing. Oral administration of DCI has also
been shown to significantly reduce plasma
glucose without elevating insulin levels in
insulin-resistant rhesus monkeys.
In humans, an unpublished, double-blind,
placebo-controlled trial examining effects of
DCI in type 2 diabetics found administration
of 1,200 mg/day of DCI for 28 days produced
a decrease in blood glucose levels during
3-hour glucose tolerance testing. In a
subgroup of subjects with elevated free fatty
acid levels, enhancement in glucose disposal
was marked and statistically significant. In
both the main group and subgroup, DCI
administration also led to significant
beneficial modifications of blood pressure,
serum cholesterol, and triglyceride levels.
Published clinical research on DCI has
focused primarily on women with polycystic
ovarian syndrome (PCOS), a condition
characterized by enlarged, cystic ovaries,
oligo- or anovulation, menstrual irregularities,
and increased ovarian androgen secretion.
PCOS is also associated with insulin
resistance and its many sequelae including
hyperinsulinemia,
impaired
glucose
tolerance, obesity, dyslipidemia, hypertension, and increased risk for type 2 diabetes.
Hyperinsulinemia in women with PCOS is
believed to play a significant contributory
role in the development of ovulatory abnormalities and hyperandrogenism. In one
clinical trial, administration of 1,200 mg/day
of DCI to 22 obese women with PCOS for
6-8 weeks significantly diminished glucosestimulated plasma insulin levels compared
to baseline. Women taking DCI also
experienced marked improvements in
ovulatory function, waist-to-hip measurements,
serum androgen, triglyceride, and blood
pressure levels. Similar results were obtained
in a placebo-controlled study utilizing 600
mg/day of DCI in 10 lean women with PCOS
for 6-8 weeks. In this study, DCI administration significantly improved plasma glucose
and insulin levels during glucose tolerance
testing. In addition, measures of whole body
insulin sensitivity increased by 84%
(compared to a 14% decline in the placebo
group); ovulation occurred in 6 of 10 women
(vs 2 of 10 in the placebo group); serum free
testosterone levels were diminished by >70%
(vs <5% in the placebo group); and blood
pressure, serum cholesterol, and triglyceride
levels were all significantly improved.
Poor Bioavailability of Dietary Sources
DCI is present in a number of foods, but
dietary intake may be inadequate to meet
physiological requirements. Most DCI in foods
exists in a galactosyl form requiring alphagalactosidase for hydrolysis and absorption.
As this enzyme is not found in human
digestive secretions, a significant portion of
dietary DCI may not be bioavailable.
Additionally, some dietary forms of DCI exist
as methylated derivatives which may be
ineffective in improving insulin sensitivity
or glucose tolerance according to several
recent studies. Dietary myo-inositol could
theoretically support insulin-mediated
glucose metabolism via bioconversion to
DCI, but animal studies indicate this
conversion is markedly impaired in insulinsensitive tissues. Supplementation with DCI
therefore appears be the most efficient and
effective means of replenishing this nutrient
and thereby ensuring optimal insulin
activity and blood glucose management.
ProThera’s new D-Chiro-Inositol is designed
for persons who wish to support normal
insulin function and protect against the
harmful effects of sustained elevated blood
glucose levels. Men or women at increased
risk for developing insulin resistance or with a
personal or family history of blood glucose
abnormalities may benefit the most from this
formula. Derived from carob seed pods, each
capsule of D-Chiro-Inositol provides 150 mg
of DCI in its free and most bioavailable form.
Take two capsules daily with food for
normal maintenance, or up to four capsules
per day for maximum support.
Supplement Facts
Serving Size 1 Capsule • Servings Per Container 60
Amount Per Capsule
D-Chiro-Inositol**
150 mg*
*Daily Value not established.
Other Ingredients: Vegetarian capsule (hydroxypropyl methylcellulose, water),
L-leucine, cellulose, and silicon dioxide.
** Chirositol™ brand, a trademark of Cyvex Nutrition, Inc.
DCH 60 vegetarian capsules
References and further information available on request.
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The information contained in this publication is intended for educational purposes only. It is not provided in order to diagnose, prevent, or treat any disease, illness, or injured condition of the body, and
the copyright owner accepts no responsibility for such use. Non-medical professionals should consult with their healthcare provider regarding their health condition. It is the responsibility of the healthcare
provider to make his or her own determination of the usefulness and applicability of any information contained herein.