Inositol: Benefits, Side Effects, Interactions and Recommended Dosages

Sometimes referred to as vitamin B8, it occurs naturally in foods like fruits, beans, grains, and nuts.

Your body can also make inositol from the carbohydrates you eat.

However, research suggests that additional inositol in supplements may have numerous health benefits.

This article looks at the benefits, recommended dosages, and potential side effects of inositol supplements.

What is inositol?

Although it is often referred to as vitamin B8, inositol is not a vitamin but a type of sugar with several essential functions.

Inositol plays a structural role in your body as a significant component of cell membranes.

It also influences the action of insulin, an essential hormone for blood sugar control. Also, it affects chemical messengers in the brain, such as serotonin and dopamine.


Rich sources of inositol include:

  • Grain.
  • Beans.
  • Walnuts.
  • Fruits.
  • Fresh vegetables.

However, supplemental inositol doses are often higher. Researchers have studied the benefits of doses of up to 18 grams per day, with promising results and few side effects.


Inositol is a type of sugar that helps provide structure to your cells. It also affects the hormone insulin and the function of chemical messengers in the brain.


It May have mental health benefits.

Inositol can help balance essential chemicals in your brain, including those believed to affect your moods, such as serotonin and dopamine.

Interestingly, researchers have found that some people with depression, anxiety, and compulsive disorders have lower levels of inositol in the brain.

Although more research is needed, several studies suggest that inositol has the potential to be an alternative treatment for mental health conditions. It also appears to have fewer side effects than traditional medications.

Panic disorder

While research is still limited, inositol supplements may help treat panic disorder, a severe form of anxiety.

People with panic disorder experience frequent panic attacks and sudden feelings of intense fear.

Symptoms include:

  • Fast heartbeat
  • Difficulty breathing.
  • Dizziness
  • Sweating
  • Tingling or numbness in the hands.

In one study, 20 individuals with panic disorder took an 18-gram inositol supplement or a common anti-anxiety medication every day.

Those who took inositol had fewer panic attacks per week than those who took the anxiety medication.

Similarly, in a 4-week study, people experienced fewer and less severe panic attacks when taking 12 grams of inositol per day.


Inositol can improve symptoms of depression, but research has had mixed results.

For example, an early study showed that taking a 12-gram inositol supplement every day for four weeks improved symptoms in people with depression.

In contrast, subsequent studies were unable to show any significant benefit.

Overall, there is not yet enough evidence to say whether inositol has an actual effect on depression.

Bipolar disorder

As with other mental health conditions, research on the effects of inositol and bipolar disorder is limited. However, the results of the preliminary studies look promising.

For example, a small study in children with bipolar spectrum disorders showed reduced symptoms of mania and depression when 3 grams of omega-3 fatty acids and up to 2 grams of inositol were taken daily for 12 weeks.

Additionally, studies suggest that 3-6 grams of inositol taken daily can help reduce the symptoms of psoriasis caused by lithium, a common medication used to treat bipolar disorder.


Although more research is needed, inositol shows potential as an alternative treatment option for mental health conditions, including panic disorder, depression, and bipolar disorder.

May improve symptoms of PCOS.

Polycystic ovary syndrome (PCOS) is a condition that causes hormonal imbalances in women, which can lead to irregular periods and infertility.

Weight gain, high blood sugar, and undesirable cholesterol and triglyceride levels also concern PCOS.

Inositol supplements can improve PCOS symptoms, particularly when combined with folic acid.

For example, clinical studies suggest that daily doses of inositol and folic acid can help lower blood triglyceride levels. They can also improve insulin function and slightly lower blood pressure in PCOS patients.

Additionally, preliminary research found that the combination of inositol and folic acid can promote ovulation in women with PCOS fertility problems.

In one study, 4 grams of inositol and 400 mcg of folic acid taken daily for three months induced ovulation in 62% of treated women.


Inositol can help lower blood triglyceride levels, improve insulin function, lower blood pressure, and promote ovulation in women with polycystic ovary syndrome (PCOS).

May Help Control Metabolic Syndrome: Risk Factors

Clinical studies suggest that inositol supplements may benefit people with metabolic syndrome.

A metabolic syndrome is a group of conditions that increase the risk of chronic diseases, including heart disease and type 2 diabetes.

Specifically, five conditions are associated with metabolic syndrome:

  • Excess fat in the stomach area.
  • High levels of triglycerides in the blood.
  • Low “good” levels of HDL cholesterol.
  • High blood pressure
  • High blood sugar

In a one-year clinical study in 80 women with metabolic syndrome, 2 grams of inositol twice daily reduced blood triglyceride levels by an average of 34% and total cholesterol by 22%.

Improvements in blood pressure and blood sugar were also seen.

Surprisingly, 20% of the women taking inositol supplements no longer met the criteria for metabolic syndrome at the end of the study.


Inositol can help control metabolic risk factors by helping to lower blood triglyceride levels, blood pressure, and blood sugar. It can also improve cholesterol levels.

Can prevent diabetes during pregnancy

Some women experience high blood sugar levels during pregnancy. This condition is called gestational diabetes (GDM).

In animal studies, inositol has been directly linked to the function of insulin, a hormone that regulates blood sugar levels.

Only a few studies are available on the supplement and DGM in humans. However, some suggest that a combination of 4 grams of myoinositol and 400 mcg of folic acid may help prevent GDM when taken daily during pregnancy.

However, more research is needed, as other studies have not shown the same effects.


Inositol can help prevent high blood sugar levels during pregnancy when taken in combination with folic acid, but more studies are needed to confirm this effect.

Other potential benefits

Inositol has been studied as a potential treatment option for many conditions.

In addition to those already mentioned, research suggests that inositol may be helpful in the following conditions:

  • Respiratory distress syndrome: In premature newborns, inositol appears to help treat breathing problems in underdeveloped lungs.
  • Type 2 diabetes: A preliminary study suggests that inositol and folic acid taken daily for six months can help control blood sugar in people with type 2 diabetes.
  • Obsessive-compulsive disorder (OCD): A small study suggests that 18 grams of inositol taken daily for six weeks can reduce OCD symptoms.

Inositol is a potential treatment option for premature babies with respiratory distress syndrome.

It can also help control blood sugar in people with type 2 diabetes and can reduce the symptoms of obsessive-compulsive disorder.

Side effects and interactions

Inositol supplements appear to be well tolerated by most people.

However, mild side effects have been reported with doses of 12 grams per day or more. These include:

  • Sickness.
  • Gases.
  • Difficulty in sleeping.
  • Headache.
  • Dizziness
  • Fatigue.

Pregnant women have taken up to 4 grams of inositol daily in studies with no adverse effects, although more research is needed in this population.

There are also preliminary studies to determine the safety of supplements during breastfeeding. However, breast milk appears to be naturally rich in inositol.

Also, it is not clear whether inositol supplements are safe for long-term use. In most studies, inositol supplements were only taken for a year or less.

As with any supplement, talk to your doctor before taking inositol.


Inositol supplements are associated with very few and only mild adverse effects. More research is needed to determine its safety in pregnant and lactating women and long-term use.

Recommended dosage

There are two primary forms of inositol used in supplements, namely Myo-inositol (MYO) and D-chiro-inositol (DCI).

Although there is no official consensus on the most effective type and dosage, the following appear to be effective in research studies:

  • For mental health conditions: 12-18 grams of MYO once a day for 4-6 weeks.
  • For PCOS: 1.2 grams of ICD once a day, or 2 grams of MYO and 200 mcg of folic acid for six months.
  • For metabolic syndrome: 2 grams of MYO twice a day for one year.
  • To control blood glucose in gestational diabetes: 2 grams of MYO and 400 mcg of folic acid twice a day during pregnancy.
  • To control blood glucose in type 2 diabetes: 1 gram of ICD and 400 mcg of folic acid once a day for six months.

While these doses of inositol appear to be helpful for certain short-term conditions, more research is needed to determine if they are safe and effective for more extended periods.


There is no official consensus on recommended doses of inositol. The amount and type of inositol supplement vary depending on the condition.

The bottom line

Research suggests that inositol may help people with mental health and mental problems, such as panic disorder, depression, bipolar disorder, polycystic ovary syndrome, metabolic syndrome, and diabetes.

It appears safe for most people and causes only mild side effects if they occur in daily doses of up to 18 grams.

While your diet likely contains small amounts of inositol, taking a supplement may benefit some.

Always discuss supplement use with your healthcare provider first.