D-chiro inositol (DCI) is a nutritional substance which first became of interest in 1999 when an article entitled “Ovulatory and metabolic effects of d-chiro inositol in the polycystic ovary syndrome” appeared in the New England Journal of Medicine by a group of researchers working for Insmed, an American drug development company. Insmed was funding the study of DCI in relation to it’s potential as a treatment for PCOS and Type II diabetes, however, in September 2002 they discontinued the entire program after Phase II clinical trials of DCI or INS-1 as they called it, ended with disappointing results, namely a lack of statistically significant improvements against it’s key efficacy measures. In respect to PCOS, this meant an increased rate of ovulation, however, despite the trial not achieving an increased rate of ovulation, there was an increased rate of pregnancy in participants taking the d-chiro inositol supplement.
6 months prior to this, Insmed announced that they would be forming a partnership with a privately held clinical genomics company called Oxagen to investigate the genetic profile associated with PCOS and other metabolic disorders related to insulin resistance, currently believed to be the root cause of the symptoms associated with PCOS, such as weight gain, hormonal imbalances which can lead to hirsuitism, alopecia, irregular menstrual cycles and even infertility.
More recent studies have found that DCI supplementation in women with PCOS reduces their amount of excess insulin in their blood, which in turn reduces the amount of male hormones (androgens) and their effects on head hair loss and increased facial and body hair, restoring a menstrual cycle in women who were previously anovulatory and even lowering the risk of heart disease, stroke and diabetes, through lowering blood pressure, blood triglycerides and LDL (bad) cholesterol.
References to Studies on D-Chiro Inositol & Myo-Inositol, Most Recent First:
2009 – Constantino D, Minozzi G, Minozzi E, Guaraldi C “Metabolic and Hormonal Effects of Myo-Inositol in Women With Polycystic Ovarian Syndrome – A double blind trial”. Eur Rev Med Pharmacol Sci Mar-Apr; 13 (2):105-10. PMID: 19499845.
2002 – Sun TH, Heimark DB, Nguygen T, Nadler JL, Larner J “Both myo-inositol to chiro-inositol epimerase activities and chiro-inositol to myo-inositol ratios are decreased in tissues of GK type 2 diabetic rats compared to Wistar controls”. Biochem. Biophys. Res. Commun. 293 (3): 1092-8. PMID 12051772.
2002 – Larner J ”D-chiro-inositol–its functional role in insulin action and its deficit in insulin resistance”. Int. J. Exp. Diabetes Res. 3 (1): 47-60. PMID 11900279.
2002 – Luorno MJ, Jakubowicz DJ, Baillargeon JP, et al “Effects of D-chiro-inositol in lean women with the polycystic ovary syndrome”. Endocrine practice 8 (6): 417-23. PMID 15251831.
2000 – Nestler JE, Jakubowicz DJ, Iuorno MJ “Role of inositolphosphoglycan mediators of insulin action in the polycystic ovary syndrome”. J.Pediatr. Endocrinol. Metab. 13 Suppl 5: 1295-8. PMID 11117673.
1999 – Nestler JE, Jakubowicz DJ, Reamer P, Gunn RD, Allan G ”Ovulatory and metabolic effects of D-chiro-inositol in the polycystic ovary syndrome”. N. Engl. J. Med. 340 (17): 1314-20. PMID 10219066.