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D-Chiro-Inositol (DCI)

D-Chiro-Inositol

Research reviewed: Up until 03/2026

D-Chiro-Inositol (D-Chiro-Inositol (DCI)) is a dietary supplement with 7 published peer-reviewed studies involving 680 participants, researched for PCOS Management, Insulin Resistance, Ovulation & Fertility and 1 more areas.

7
Studies
680
Participants
1999–2018
Research Span

Evidence at a Glance

Strength is scored by study design, sample size, study type, and outcomes

Overall: Very Strong Evidence

PCOS Management

Moderate
2 studies 1 of 2 positive 44 participants

Insulin Resistance

Moderate
2 studies 1 of 2 positive 83 participants

Ovulation & Fertility

Moderate
1 study 1 of 1 positive 31 participants

Hormonal Balance

Strong
2 studies 2 of 2 positive 20 participants

Research Visualised

Visual breakdown of the clinical data.

Study Quality Breakdown

What types of studies were conducted

4/7
Randomised
4/7
Double-Blind
3/7
Placebo-Controlled

Participants Per Study

Larger samples = more reliable results

Study 1 (1999)
44
Study 2 (2016)
0
Study 1 (2016)
46
Study 2 (2008)
37
Study 1 (2005)
31
Study 1 (2018)
0
Study 2 (2004)
20

Research Timeline

When the studies were published

1
1999
1
2004
1
2005
1
2008
2
2016
1
2018

All Studies

Detailed breakdown of each trial. Click to expand.

PCOS Management

1

To evaluate the ovulatory and metabolic effects of D-chiro-inositol in women with polycystic ovary syndrome.

1999 44 participants 6–8 weeks 1,200 mg D-chiro-inositol once daily
Human Study RCT Double-Blind Placebo Positive

Study Type

Randomised, double-blind, placebo-controlled

Purpose

To evaluate the ovulatory and metabolic effects of D-chiro-inositol in women with polycystic ovary syndrome.

Dose

1,200 mg D-chiro-inositol once daily

Participants

44 women with PCOS and insulin resistance

Duration

6–8 weeks

Results

D-chiro-inositol significantly increased ovulation rate (86% vs 27% placebo), decreased serum androgens, improved insulin sensitivity, and reduced blood pressure in women with PCOS.

How They Measured It

Ovulation rate, serum androgens, fasting insulin, HOMA-IR, testosterone, LH, FSH

Read full study
2

To describe the rationale, biochemical, and clinical data related to the use of inositols in PCOS.

2016 ? participants Various Various, typically 40:1 myo:DCI ratio
Human Study Mixed

Study Type

Review

Purpose

To describe the rationale, biochemical, and clinical data related to the use of inositols in PCOS.

Dose

Various, typically 40:1 myo:DCI ratio

Participants

Systematic review

Duration

Various

Results

Both myo-inositol and D-chiro-inositol improve PCOS outcomes including insulin sensitivity, ovulation rates, and hormonal profiles. The physiological 40:1 MI:DCI ratio provides optimal clinical benefit.

How They Measured It

Review of myo-inositol and D-chiro-inositol RCTs in PCOS

Read full study

Insulin Resistance

1

To evaluate the effect of combined myo-inositol and D-chiro-inositol on endocrine parameters and insulin resistance in young overweight PCOS women.

2016 46 participants 6 months MI 550 mg + DCI 13.8 mg daily (40:1 ratio) for 6 months
Human Study RCT Double-Blind Placebo Positive

Study Type

Randomised, double-blind, placebo-controlled

Purpose

To evaluate the effect of combined myo-inositol and D-chiro-inositol on endocrine parameters and insulin resistance in young overweight PCOS women.

Dose

MI 550 mg + DCI 13.8 mg daily (40:1 ratio) for 6 months

Participants

46 PCOS patients (randomised to MI+DCI vs folic acid)

Duration

6 months

Results

The MI+DCI combination significantly improved insulin resistance (HOMA index), reduced androgens, normalised LH/FSH ratio, and improved hormonal profile compared to placebo. Menstrual cycles regularised in the treatment group.

How They Measured It

FSH, LH, 17β-oestradiol, SHBG, androstenedione, free testosterone, DHEAS, HOMA index, fasting glucose and insulin

Read full study
2

To investigate insulin-stimulated release of D-chiro-inositol-containing mediators and their correlation with insulin sensitivity in PCOS women.

2008 37 participants Crossover assessment N/A (observational)
Human Study Positive

Study Type

Prospective observational study

Purpose

To investigate insulin-stimulated release of D-chiro-inositol-containing mediators and their correlation with insulin sensitivity in PCOS women.

Dose

N/A (observational)

Participants

37 women with PCOS and 18 healthy controls

Duration

Crossover assessment

Results

DCI-containing mediator release was significantly blunted in insulin-resistant PCOS women compared to insulin-sensitive controls. DCI-IPG release correlated with insulin sensitivity, confirming DCI's role in insulin signalling.

How They Measured It

DCI-IPG mediator levels, HOMA-IR, glucose disposal rate

Read full study

Ovulation & Fertility

1

To assess the effect of D-chiro-inositol on ovulation in anovulatory PCOS women.

2005 31 participants 16 weeks 600 mg D-chiro-inositol daily
Human Study RCT Double-Blind Positive

Study Type

Randomised, double-blind, controlled

Purpose

To assess the effect of D-chiro-inositol on ovulation in anovulatory PCOS women.

Dose

600 mg D-chiro-inositol daily

Participants

31 anovulatory PCOS women

Duration

16 weeks

Results

D-chiro-inositol significantly improved ovulation rates compared to placebo. Serum androgens decreased and SHBG increased. Pregnancy rate was higher in the DCI group.

How They Measured It

Ovulation rate (confirmed by serum progesterone), pregnancy rate

Read full study

Hormonal Balance

1

To meta-analyse the effects of inositol supplementation on hormonal and metabolic outcomes in PCOS.

2018 ? participants Various (3–6 months) Various myo-inositol and DCI protocols
Human Study Positive

Study Type

Meta-analysis

Purpose

To meta-analyse the effects of inositol supplementation on hormonal and metabolic outcomes in PCOS.

Dose

Various myo-inositol and DCI protocols

Participants

Meta-analysis of multiple RCTs

Duration

Various (3–6 months)

Results

Inositol supplementation significantly reduced total testosterone, fasting insulin, HOMA-IR, and LH, while increasing SHBG in women with PCOS. Both myo-inositol and DCI showed hormonal benefits.

How They Measured It

Testosterone, SHBG, LH, FSH, fasting insulin, HOMA-IR across RCTs

Read full study
2

To evaluate the effect of D-chiro-inositol on androgens and insulin resistance in postmenopausal women with type 2 diabetes.

2004 20 participants 6 weeks 600 mg D-chiro-inositol daily
Human Study RCT Double-Blind Placebo Positive

Study Type

Randomised, double-blind, placebo-controlled

Purpose

To evaluate the effect of D-chiro-inositol on androgens and insulin resistance in postmenopausal women with type 2 diabetes.

Dose

600 mg D-chiro-inositol daily

Participants

20 postmenopausal women with T2DM

Duration

6 weeks

Results

D-chiro-inositol significantly improved insulin sensitivity, reduced fasting insulin and HOMA-IR, and was well tolerated in postmenopausal women with type 2 diabetes.

How They Measured It

Fasting insulin, HOMA-IR, testosterone, urinary inositol excretion

Read full study

Frequently Asked Questions

Common questions about D-Chiro-Inositol research

What does the research say about D-Chiro-Inositol?

There are currently 9 peer-reviewed studies on D-Chiro-Inositol (D-Chiro-Inositol (DCI)), involving 680 total participants. Research covers PCOS management, Insulin resistance, Ovulation & fertility and 1 more areas. The overall evidence strength is rated as Very Strong.

How strong is the evidence for D-Chiro-Inositol?

The evidence is currently rated as "Very Strong Evidence". This rating is based on study design quality (randomisation, blinding, placebo controls), sample sizes, study types (7 human studies), and reported outcomes.

What health goals has D-Chiro-Inositol been studied for?

D-Chiro-Inositol has been researched for: PCOS management, Insulin resistance, Ovulation & fertility, Hormonal balance. Each area has its own body of evidence which you can explore in the study breakdowns above.

Are the studies on D-Chiro-Inositol based on human trials?

Yes, 7 out of 9 studies are human trials. Human trials carry more weight in our evidence scoring system.