Anxiety disorder, depression and obsessive compulsive disorder blight the lives of hundreds of millions of people across the globe, with the World Health Organization reporting that 115 million people globally suffer from depression alone.
Rates of these disorders are higher in developed, wealthy nations like the United States, and while effective (and expensive) pharmaceutical treatments help a great many people, they don’t work for everyone and can unfortunately cause distressing side effects. Side effects which make sufferers reluctant to use these medications.
For people unable or unwilling to use prescription drugs to manage their condition, natural dietary supplements are a source of great interest and one supplement that shows some promise is Inositol.
In this article we’ll take a look at the available evidence for Inositol as an aid in managing the symptoms of anxiety, depression, and OCD.
What Is Inositol?
Inositol (also known as also known as hexahydroxy cyclohexane and cyclohexanehexol) is a naturally occurring non-essential nutrient necessary for proper cell formation and growth, nerve transmission and transportation of fats in the body.
Inositol is also believed to positively impact the action of serotonin – a neurotransmitter that plays a large role in depression, anxiety and obsessive compulsive disorder.
Non-essential doesn’t mean that we don’t need Inositol because we most assuredly do. This term simply means that we manufacture Inositol within the body, as opposed to being reliant on food sources like we are for nutrients like vitamin C and vitamin E.
Inositol is synthesized from the glucose present in the body and is particularly plentiful in the spinal fluid of healthy individuals. In patients with depression, decreased spinal fluid Inositol levels have been reported.
Although nine forms of Inositol exist, the most abundant form of Inositol found within cellular membranes – and the one commonly taken as a supplement – is Myo-inositol, which makes up 95% of free Inositol in the body.
Myo-inositol was first isolated in the 1800’s and by the middle of the last century researchers had discovered the role it played in biological processes. At that time Inositol was classified as an essential vitamin – vitamin B8.
Later research led to the realization that our bodies make their own Inositol and this is why the nutrient was reclassified as non-essential.
Adequate Inositol levels are linked with good health, while low levels have been linked to a number of psychiatric conditions. These include:
- Attention Deficit Hyperactivity Disorder
- Anxiety Disorder
- Obsessive Compulsive Disorder.
Preliminary evidence suggests that correcting low Inositol levels may improve symptoms of these disorders.
While Inositol is present in many foods, the amount available from these foods isn’t sufficient to have a positive therapeutic effect on mental health.
For this reason, individuals seeking to relieve their symptoms with Inositol use high-dose Myo-inositol supplements.
The initial research responsible for the popularity of Inositol supplementation was carried out by the Ministry of Mental Health at Ben Gurion University, and later published in the Journal of Clinical Psychology.
This research took the form of a double blind study and found that Inositol was an effective treatment for general anxiety disorder, panic disorder and obsessive compulsive disorder.
Inositol may not work equally well for males and females, with women seeing more significant effects than men.
Dietary Sources of Inositol
Small amounts of Inositol can be obtained from beans, nuts, seeds, meats, organ meats, fish, fruits, grains, vegetables and dairy products.
The best food sources are whole grains and citrus fruits which contain more Inositol than foods like meat and dairy.
For example, oranges contain 3.07 mg Inositol per gram, stone ground wheat contains 11.5 mg per gram, ground beef 0.37 mg per gram, and milk contains 0.04 mg per gram.
An average intake of 2500 calories a day from a varied, healthy diet, should result in consumption of around 900 mg of inositol per day and diet can be tailored to deliver higher amounts.
Inositol Effects on Obsessive Compulsive Disorder
Obsessive disorder can be very difficult to treat successfully and SSRI treatment only has a limited degree of effectiveness in 40-60% of patients. What’s more SSRI’s are associated with a wide range of adverse side effects.
Recent research has indicated that certain nutritional supplements including Myo-inositol are able to modulate the glutamatergic and serotonergic pathway dysregulation thought to be associated with OCD.
During a double blind crossover trial, 13 individuals diagnosed with obsessive compulsive disorder were given 18 grams of Inositol per day during the first six week stage of the trial and a placebo (inert sugar pill) during the second six week stage.
Their symptoms were measured using the Yale-Brown Obsessive Compulsive Scale, and the results of the study revealed patients had better scores on the scale when taking Inositol compared to their scores when taking the placebo.
Another study using 18g Inositol per day in conjunction with serotonin reuptake inhibitors noted that while some patients had a favorable response, these patients were in the minority, indicating that Inositol produces better results when used alone.
Inositol Effects on Anxiety
The method through which Myo-inositol acts to reduce anxiety symptoms isn’t fully understood.
While researchers know that individuals with severe anxiety disorder tend to have very low concentrations of Inositol in their cerebrospinal fluid, it’s not clear if Inositol deficiency causes the anxiety, or if anxiety disorder generates conditions that deplete Inositol reserves.
A low Inositol level is also unlikely to be the sole factor in anxiety, so while taking inositol can improve symptoms you shouldn’t take it with the expectation that it will be a wonder cure.
Though the specific Inositol mechanisms haven’t been fully determined by researchers, many suspect that Myo-inositol may improve monoaminergic neurotransmission. Monoaminergic means “working on the monoamine neurotransmitters”, which include serotonin and dopamine.
It is thought that Inositol mediates serotonergic signaling and induces an anti anxiety (anxiolytic) effect. Additionally, Inositol elicits a range of neurophysiologic effects, including fat transportation, calcium ion release and protein kinase C activation which could also contribute to the anxiety reducing effect.
A study carried out by the Ministry of Mental Health Center at Ben Gurion University, found that patients with anxiety disorders taking 18 grams per day of Myo-inositol had similar results to those experienced when taking 150mg per day of the prescription antidepressant fluvoxamine.
Study participants underwent 1 month of Inositol treatment followed by 1 month of fluvoxamine. During the Inositol phase of the trial, participants experienced 4 fewer panic attacks per week. In the fluvoxamine phase, panic attacks were reduced by 2.4 per week.
Common side effects of fluvoxamine include nausea and fatigue. Anxiety sufferers who are reluctant to use prescription drugs because of side effects may benefit from Inositol which has few adverse effects.
While Inositol has shown effectiveness for general anxiety and panic attacks, it hasn’t shown any benefit for patients suffering from Post Traumatic Stress Disorder (PTSD).
Inositol can also improve sleep quality which is often compromised in those suffering from anxiety, and lack of restorative sleep tends to make anxiety symptoms worse.
EEG brain scans on individuals with anxiety show that there are excess beta waves and not enough alpha, delta and theta waves present during sleep which can negatively affect the ability to experience deep sleep.
Large scale clinical trials have not yet been conducted on Inositol for anxiety disorder so it’s impossible to state a probable benefit level with any certainty.
Inositol Effects on Depression
Post mortem examinations on individuals who have committed suicide reveal lower levels of Inositol in the frontal cortex region of the brain.
Inositol has been studied for its effects on depression. A small double blind trial found that 12 grams of Inositol administered daily for 4 weeks led to improved scores on the Hamilton Depression Rating Scale (HDS).
During the trial, 13 depressed patients who discontinued their medication were given Inositol every day while 15 were given a placebo (inert sugar pill).
Improvements to scores on the HDS were significantly greater for those taking Inositol than for those taking the placebo. The score results were as follows:
For the Inositol group, the overall score on the HDS was 64% of the baseline (33.4 to 21.6).
In the placebo group the HDS score was 87% of baseline (32.9 to 28.9).
These results suggest that Inositol is moderately effective when used in depressed patients.
When Inositol use was discontinued, half of the patients relapsed. The study also found that females benefited from Inositol to a greater degree than males.
Inositol appears to be ineffective in patients who don’t respond to SSRI drugs. Studies using 12 grams of Inositol in these individuals over a 4 week period have failed to find an antidepressant effect.
Finally, Inositol used in conjunction with SSRI’s hasn’t shown any benefit over using SSRI’s by themselves.
Is Inositol Safe?
Inositol is generally safe and doses of 18 grams per day have not caused any serious adverse effects.
However, it’s important to note that no studies have been carried out into the long term effects of Inositol.
Inositol Side Effects
Most people take Inositol without experiencing any problems, but Inositol does have the potential to cause some side effects, particularly when you first take it in large doses.
Because larger doses may be needed for symptom relief in anxiety disorder, depression and OCD, you should be aware of the side effects that you may have to deal with.
Side effects can include:
As your body adjusts to Inositol, any side effects should disappear or cease altogether.
Some people have found that side effects become apparent even at low doses, and diarrhea seems to be the most common problem encountered in particularly sensitive people.
It may be a good idea to begin taking Inositol at the weekend, when you can stay at home and be close to your bathroom, just in case.
Who Shouldn’t Take Inositol?
Inositol may not be suitable for use during pregnancy or nursing. Several studies have used 4 grams per day during pregnancy with no adverse results, but amounts greater than this have not been tested on pregnant women.
If you get relief from Inositol and want to use it during a pregnancy, discuss your intention with your doctor to make sure that your baby won’t be affected.
While there are currently no known drug contraindications for Inositol, anyone taking prescription medication should always check with their doctor before using large doses of any supplement.
Inositol may not be suitable for people suffering from bipolar disorder. The substance may have caused a manic episode in a bipolar patient whose condition was under control at the time.
The hospitalization of this individual was not related to direct supplementation with Inositol but to his heavy consumption of an energy drink containing Inositol, caffeine, taurine and other ingredients.
If you have bipolar disorder, you should consult your doctor before using Inositol.
Children do take Inositol and many parents report good results, but you should always check with your family pediatrician before use.
The recommended dose for general Inositol supplementation is 500 milligrams twice a day; however, to treat anxiety, panic disorder and OCD, you may need to take higher amounts.
The exact effective dose, will vary from person to person and it’s sensible to begin with lower doses and work your way up.
Doses used in the studies generally fall in the 12 to 18 gram per day range, but many users report beneficial results with lower doses, so it’s important to experiment and find the dose that gives you the best results.
Taking a lower dose – 2 grams (or less) twice a day to begin with – will save you money and a lower dose will reduce the chance of side effects.
Inositol Withdrawal Symptoms
At this time there are no known withdrawal symptoms associated with stopping Inositol supplementation.
Contrast this with the often horrendous withdrawal symptoms that are known to affect a significant number of patients when they attempt to stop taking SSRI’s. Symptoms so severe that the only option is to continue taking the medication, even when the medication no longer works to control symptoms.
Using Inositol With Tryptophan or 5-HTP
Tryptophan and 5-HTP are both popular supplements used to improve the symptoms of OCD, depression and anxiety, and Inositol makes a good addition to this supplement regime.
A good starting point if you want to use Inositol with these other supplements is to take 2 grams of Inositol per 500 mg of tryptophan.
Where To Buy Inositol
Inositol is widely available. You should be able to find 500 mg capsules in natural food stores as well as in the dietary supplement section of large pharmacies, and numerous brands are also available on Amazon and from other online retailers.
However, given the large dose needed to see positive effects on anxiety, depression and obsessive compulsive disorder, it will be more cost effective to purchase your Inositol supplement as a bulk powder.
For example the ‘Jarrow Formulas Inositol Powder’ available on Amazon costs $15.49 for 227 grams. While their 750 mg capsules cost $10.39 for 100 capsules giving you a total of just 75 grams of Inositol.
Unlike many powdered supplements, Inositol doesn’t have an unpleasant taste, so it’s easy to take unencapsulated. Simply mix your desired amount with water.
The gel cap form of Inositol supplement is more effective than powders or capsules and using this form of the supplement allows you to reduce the dose taken. Gel caps are harder to find and do cost more.
A 2 – 4 gram dose of powder or capsule Inositol can be reduced to 600 mg – 1200 mg of Inositol in the gel cap form.
Inositol is a natural dietary supplement usually taken in large doses and often resulting in some degree of symptom relief for anxiety disorder (though not symptoms of PTSD), depression, and OCD.
The recommended dose ranges from 1 gram per day up to 18 grams per day, which is the largest amount tested in trials.
The supplement is widely available and relatively inexpensive, especially if you purchase the loose powder.
Taking Inositol powder is very easy. The powder quickly dissolves in water and has a pleasantly sweet flavor.
Side effects tend to be minor and short lived, and are most common during the early days of large dose Inositol supplementation.
Unlike SSRI’s that are the standard treatment for anxiety, depression and OCD, Inositol has no known withdrawal effects. You can try Inositol and if it doesn’t work, you’ll be in no worse shape than you were before you tried it.
Generally, Inositol is considered to be a very safe supplement although no studies have reported on the long term use of high doses of Inositol.
To find out if Inositol will work for you, you only need take the supplement for 4 weeks and then asses how you feel. Four weeks is the time span used in most of the trials that found Inositol beneficial.
A supply of Inositol powder used for 4 weeks at a dose of 18 grams per day (540 grams) would only cost you $1 per day, making this a very affordable supplement to try, and well worth the ongoing cost if it proves to be effective for you.
While some studies have demonstrated beneficial outcomes when taking Inositol it should be remembered that all of the studies used a very small sample group and as such its difficult to draw broad conclusions.
If you suffer with anxiety, depression or OCD and don’t want to take prescription drugs, Inositol by itself may be able to offer you some relief or form part of a multifaceted natural therapy.