Category Archives: iositol

Myo-inositol: a safe and effective supplement for PCOS

Recently, there has been a lot of interest in the role of inositol in the treatment of polycystic ovarian syndrome (PCOS). A recent systematic review has weighed up the evidence behind the claims (1).

The systematic review looked at the clinical outcomes of myo-inositol supplementation as a treatment for PCOS. Specifically, it examined the effects of myo-inositol on ovarian function and metabolic and hormonal parameters in PCOS sufferers.

What is inositol?

Inostiol is crucial for a whole range of processes from nerve signals to the breakdown of fats

Inositol is a substance that occurs naturally in the human body, and is also present in foods such as fruits, seeds, grains and nuts. It was once thought to be a member of the B Vitamin group, but this is not strictly true – vitamins are essential nutrients that the body cannot make on its own, whereas our body can actually synthesise inositol from glucose.

Inositol is used by the body to form signalling molecules, and so it is crucial for a whole range of processes, from nerve signals to the breakdown of fats. There are several different forms of inositol, and the two forms that are considered helpful in PCOS are myo-inositol and d-chiro-insolitol.

How is inositol helpful in PCOS?

The researchers found evidence that suggests myo-inositol is helpful in PCOS because it decreases levels of excessive androgens. The study also found evidence that the nutrient improves the ovarian response to hormones called gonadotropins, helping to achieve regular menstrual cycles and successful ovulation.

Women with PCOS often have a defect in the way that their body processes insulin. This has a knock-on effect on other hormones and proteins. Sex hormone binding globulin (SHBG) is decreased, testosterone levels are raised, and the results are problems with acne, hirsutism (excessive hair growth) and fertility.

The insulin-signalling pathway is heavily dependent on myo-inositol. Supplementing extra myo-inositol therefore appears to correct the mal-functioning insulin pathways, reducing the signs and symptoms of PCOS.

The blights of PCOS: ovulation problems, acne and hirsuitism

Other studies echo these findings. A previous randomised controlled trial investigated the effects of myo-insolitol supplements versus placebo on ovarian function (2). Ninety-two women with PCOS were given either 2g myo-inositol twice daily, or a placebo pill for 16 weeks. At the end of the study, significantly more women in the inositol group were found to have normal levels estrogen and progesterone, and experienced normal ovulation. The women in the myo-inositol also showed a significant amount of weight loss over the study period. The researchers concluded that the results indicate “a beneficial effect of myo-inositol in women with oligomenorrhea and polycystic ovaries in improving ovarian function.”

A further study investigated the benefits of myo-inositol on symptoms such as acne and excessive hair growth in women with PCOS (3). After three months of supplementation, levels of insulin, testosterone and luteinizing hormone were significantly reduced. At the six-month mark, both hirsutism and acne had also decreased. The researchers concluded that myo-inositol is a “simple and safe treatment that ameliorates the metabolic profile of patients with PCOS, reducing hirsutism and acne.”

Myo-inositol is not considered toxic even at high doses. It has been supplemented in doses up to 18g daily without significant side-effects, though digestive symptoms may be experienced at this level (4). Of course, it is not at all necessary to supplement at such as high dose for PCOS where results are seen at levels of around 2-4g daily.

I always consider the two most important questions to ask when considering supplementation to be ‘is it safe?’ and ‘is it effective?’ In light of the supporting evidence for the safety and effectiveness of this particular nutrient, I would not hesitate to use myo-inositol alongside a low G.I diet as an initial therapeutic approach to address PCOS.


  1. Unfer V, Carlmango G, Dante G, Facchinetti F (2012) Effects of myo-inositol in women with PCOS: a systematic review of randomized controlled trials. Gynecol Endocrinol 28(7):509-15.
  1. Gerli S, Papleo E, Ferrari A, Renzo GC (2007) Randomized, double blind placebo-controlled trial: effects of Myo-inositol on ovarian function and metabolic factors in women with PCOS. European Review for Medical and Pharmacological Sciences 11: 347-354.
  1. Zacchè MM, Caputo L, Filippis S, Zacchè G, Dindelli M, Ferrari A (2009) Efficacy of myo-inositol in the treatment of cutaneous disorders in young women with polycystic ovary syndrome. Gynecol Endocrinol 25(8):508-13.
  1. Lam S, McWilliams A, leRiche J, MacAulay C, Wattenberg L, Szabo E (2006) A Phase I Study of myo-Inositol for Lung Cancer Chemoprevention. Cancer Epidemiol Biomarkers Prev 15: 1526.

Can nutrition be helpful for sufferers of obsessive compulsive disorder (OCD)?

On the 8th July this year I wrote a piece entitled “Are you tearing your hair out? Study finds nutritional supplement may help reduce compulsive behaviour”, the post was looking at a study which found that N-acetylcysteine (NAC) may be useful for sufferers of trichotillomania.  NAC is an amino acid that acts as an antioxidant in the body but also affects levels of glutamate in the brain.  Glutamate triggers excitement in the brain, lowering glutamate levels may help people who suffer with obsessive compulsive disorders.  Today I thought I would have another look at obsessive compulsive disorder (OCD) in general to assess whether any other nutritional/lifestyle advice could help.

One nutrient that seems to be coming up time and time again in the medical literature is inositol.  Insolitol is classified as a member of the vitamin B complex and is sometimes referred to as vitamin B8.  Naturally inositiol (in its myo-inositol form) is found in nuts, beans and fruit, especially cantaloupe melon, oranges, grapefruit and raisins.  It has many functions in the body, structurally it is important in some lipids (fats) and cell membranes but it also functions in insulin control pathways, nerve guidance, calcium control within cells, and serotonin activity.  Serotonin is often known as a feel-good brain chemical.  Low levels have been linked to many mood disturbances.  Low levels of insolitol in the body have also been linked with depression, bulimia, panic disorder, OCD, bipolar depression and agoraphobia.

So let’s have a closer look at the available medical studies with inositol in OCD and similar disorders.

In 1996 (1) a small, but well designed, study published in the American Journal of Psychiatry found that 18g of inositol per day for six weeks was effective at significantly reducing OCD symptoms when compared to a placebo.  In 1997 (2) another small trial found that 18g of inositol for six weeks significantly reduced scores of OCD symptoms compared when compared with placebo treatment. 

A group of researchers in 2001 (3) undertook a study to compare the effect of inositol with that of fluvoxamine in individuals with panic disorder.  Fluvoxamine is a Selective Serotonin Reuptake Inhibitor (SSRI) pharmaceutical antidepressant drug often used in OCD.  The trial participants received up to 18g/day of inositol and up to 150mg/d of fluvoxamine for a month.  Improvements on Hamilton Rating Scale for Anxiety scores, agoraphobia scores, and Clinical Global Impressions Scale scores were similar for both treatments.   In the first month, inositol reduced the number of panic attacks per week by an average of 4.0 compared with a reduction of 2.4 with fluvoxamine.  Nausea and tiredness were more common with fluvoxamine.  The authors of the study conclude that “Because inositol is a natural compound with few known side effects, it is attractive to patients who are ambivalent about taking psychiatric medication. Continuing reports of inositol’s efficacy in the treatment of depression, panic disorder, and OCD should stimulate replication studies”.

Also published in 2001 was a paper (4) which reported three case studies to show that inositol may help in the treatment of trichotollomania.  The paper describes the cases of two women with trichotillomania and one with compulsive skin picking.  They were treated with 6g inositol (which was in a powder form and taken dissolved in water or juice three times per day). The treatment lasted 8-16 weeks and all of them found their condition improved with inositol treatment.  The authors of the paper conclude: “The three cases described here suggest that inositol might be a treatment option in some patients with hair pulling and skin picking and could be considered in patients who tolerate SRIs [selective reuptake inhibitors] poorly or who are unwilling to take them,” 

These studies and case-studies certainly indicate that inositol is worth investigating further and I hope that larger trials are carried out soon.  Many OCD sufferers and sufferers of depression and other mood disturbances are unwilling to take anti-depressant drugs due to the many side-effects and a general unwillingness to take pharmaceutical mood-altering medications.  Side effects of inositol treatment are few and generally mild.  Possible side effects of high dose inositol treatment are mainly gastrointestinal symptoms such as gas, diarrhoea and abdominal cramps.  Headaches may also occur. 

How might inositol be working to help in OCD, trichotillomania and similar disorders?

As mentioned earlier inositol is involved with serotonin action in the brain. In 2001 (5) and 2002 (6) a group of researchers looked specifically at OCD and how inositol may be working to help sufferers of the condition.  There is, as yet, no conclusive answer but inositol certainly seems to be having an effect in brain cells at specific ‘receptor’ sites which are important in brain chemical signalling (dopamine and serotonin appear to be brain chemicals that are affected by inositol).  Inositol from the diet is incorporated into cell membranes of neurones, brain cells, where it serves a function in brain chemical signalling.  In addition to its role in cell signalling, inositol lipids also seem to alter receptor sensitivity, can direct membrane trafficking events, and have also been found to modulate an increasing array of complex signalling proteins in the brain (6).  Further research work is needed in order to gain firmer insights.

If you are a sufferer of OCD, trichotillomania or panic disorder and are looking for an alternative treatment to conventional antidepressants, or are interested in taking a natural substance in addition to conventional treatment it may well be worth talking to your medical doctor about inositol.  They may not be aware of the evidence, in which case you could show them this blog post and they can read the full study papers to gain a fuller perspective.  Never stop taking a conventional treatment without talking to your medical doctor first and do not start a high dose inositol treatment without first consulting a medical doctor. 

If you are suffering with trichotillomania you may also wish to contact the following online support network:  Trichotillomania Support Online.  For OCD sufferers the following charity, OCD-UK, may be a helpful point of contact.

(1) Fux, M et al.  1996.  Inositol treatment of obsessive-compulsive disorder.  American Journal of Psychiatry.  153(9):1219-1221
(2) Levine J.  1997.  Controlled trials of inositol in psychiatry.  Eur Neuropsychopharmacol.  7(2):147-155.
(3) Palatnik A et al.  2001.  Double-blind, controlled, crossover trial of inositol versus fluvoxamine for the treatment of panic disorder. J Clin Psychopharmacol. 21(3):335-9
(4) Seedat S, Stein D, Harvey B (2001), Inositol in the treatment of trichotillomania and compulsive skin picking (letter). J Clin Psychiatry 62(1):60-61.
(5) Harvey BH et al.  2001.  Chronic inositol increases striatal D(2) receptors but does not modify dexamphetamine-induced motor behavior. Relevance to obsessive-compulsive disorder.  Pharmacol Biochem Behav.  68(2):245-253.
(6) Harvey BH et al.  2002.  Defining the neuromolecular action of myo-inositol: application to obsessive-compulsive disorder.  Prog Neuropsychopharmacol Biol Psychiatry.  26(1):21-32.
Written by Ani Kowal