What is the recommended dose of Inositol?

The recommended dose is 2000--4000 mg. 40:1 myo:D-chiro ratio often used for PCOS.

When should I take Inositol?

Inositol is best taken in the morning or evening. Often split into 2 doses.

Who should take Inositol?

Inositol is most beneficial for: Women with PCOS; Those with anxiety or OCD; People with insulin resistance.

›vitamin›Inositol

vitamin

Inositol.

3.9

Reviewed by Pierson Riley — Founder, UtritionReviewed under Utrition’s editorial methodologyLast reviewed Jun 2026Allergen-free

A vitamin-like compound involved in cell signaling and insulin sensitivity.

vitaminpcosinsulinanxietyfertility

Evidence

Moderate evidence

Best time

Morning

Often split into 2 doses

Typical dose

2000–4000

Primary use

Vitamin

Quick answer

Inositol in one minute. A vitamin-like compound involved in cell signaling and insulin sensitivity. Typical dose: 2000–4000 mg. Take in the morning or evening.

What is Inositol?

Inositol is a carbocyclic sugar naturally produced by the body. Myo-inositol is the most common form; D-chiro-inositol is also used. Research supports use for PCOS, anxiety, and mood. Often taken at gram-level doses.

PCOS symptom improvement

Anxiety reduction

Insulin sensitivity

Keep reading

Evidence A

Vitamin B9 (Folate)

A water-soluble vitamin essential for DNA synthesis and cell division.

Evidence A

Vitamin D3

A fat-soluble vitamin essential for bone health and immune function.

Evidence A

Vitamin C

A water-soluble antioxidant essential for immune function and collagen synthesis.

Evidence B

Vitamin K2

A fat-soluble vitamin that directs calcium to bones rather than arteries.

Evidence A

B-Complex Vitamins

A group of eight water-soluble vitamins essential for energy metabolism.

Evidence A

Vitamin A

A fat-soluble vitamin essential for vision, immune function, and cell growth.

What is Inositol?

A vitamin-like compound involved in cell signaling and insulin sensitivity.

What the evidence says

The overall evidence grade for Inositol is B (moderate — mixed or smaller trials, reasonable mechanistic support). Good evidence for PCOS and some mental health applications.

Specific findings with supporting evidence:

Supports insulin sensitivity in PCOS. Evidence grade A.
May help anxiety and OCD. Evidence grade B.
Improves egg quality in PCOS. Evidence grade B.

Best-supported outcomes:

PCOS symptom improvement.
Anxiety reduction.
Insulin sensitivity.

Where marketing outpaces evidence:

Marketing often overstates: Fertility miracle.
Marketing often overstates: Works for everyone with anxiety.

Dose and timing

The typical effective dose for Inositol is 2000–4000 mg. 40:1 myo:D-chiro ratio often used for PCOS.

Take it in the morning and evening. Often split into 2 doses.

Who it's for, and who should skip it

Most relevant for:

Women with PCOS.
Those with anxiety or OCD.
People with insulin resistance.

Not appropriate for:

Those without specific indication.

Safety and cautions

GI effects. High doses may cause nausea or diarrhea initially.

Common mistakes

Wrong ratio of myo to D-chiro.
Underdosing.
Expecting immediate results.

Myths vs reality

A common misconception: More D-chiro is better. In reality, too much D-chiro may impair egg quality. Ratio matters.

How it interacts with other compounds

Inositol works well alongside vitamin b9 — often paired for fertility support.

Questions people ask

Myo vs D-chiro inositol? Most research uses myo-inositol or a 40:1 ratio for PCOS.

How long until effects? Typically 2-3 months for PCOS-related benefits.

Editorial note

This guide summarizes the published evidence on Inositol. It is educational content, not medical advice. Confirm with your clinician if you take prescription medications or manage a chronic condition.