Inositol is a carbohydrate found in your body, as well as in food and dietary supplements.
There are various forms of this molecule, and each of them has a chemical structure similar to the main sugar found in your blood — glucose.
Inositol plays a role in many bodily processes. Therefore, it has been studied for its potential health benefits.
Inositol supplements may help treat specific medical conditions, including some anxiety and fertility disorders. They may also have other health-promoting effects.
Here are 5 evidence-based health benefits of inositol.
Inositol affects the processes that make neurotransmitters, the molecules responsible for relaying information within your brain ().
Serotonin is one important neurotransmitter affected by inositol. This molecule has many roles in your body and impacts your behavior and mood (2).
Researchers have examined whether inositol supplements can improve symptoms associated with conditions affecting serotonin and the brain.
This includes anxiety disorders, such as panic disorder, obsessive-compulsive disorder (OCD) and posttraumatic stress disorder (PTSD).
Several studies have shown that inositol may be able to reduce the number of panic attacks in those with panic disorders (, ).
One study in 20 people with panic disorders found that 18 grams of inositol each day reduced the number of weekly panic attacks by 4 — more than the reduction of 2.4 per week seen in individuals on anxiety medication ().
Another study in people with OCD found that 18 grams of inositol each day improved symptoms better than a placebo ().
However, the small amount of research examining inositol and PTSD has not shown any benefits ().
In fact, some researchers have questioned whether inositol is effective in treating any of these anxiety disorders ().
Overall, inositol could have benefits for certain types of anxiety disorders, but more studies are needed to determine these effects.
Summary Inositol can affect the neurotransmitters in your brain, including serotonin. High doses may be beneficial for treating some forms of anxiety disorders, such as panic disorders. However, mixed results have been reported, and more research is needed.
Insulin is a hormone that is critically important for controlling blood sugar levels in your body.
Insulin resistance, a problem with your body’s ability to respond to insulin, is considered one of the key factors associated with conditions like metabolic syndrome ().
Inositol can be used to produce molecules that are involved in insulin’s action in your cells ().
Therefore, inositol has been explored for its potential to improve the body’s sensitivity to insulin — thus, reducing insulin resistance.
One six-month study in 80 postmenopausal women with metabolic syndrome found that 4 grams per day of inositol improved insulin sensitivity, blood pressure and cholesterol levels more than a placebo ().
Other research in women with gestational diabetes has also shown benefits of inositol for insulin sensitivity and blood sugar control ().
What’s more, inositol may improve insulin’s action in women with polycystic ovary syndrome (PCOS), though the results are mixed (, , ).
Summary Inositol plays a role in insulin signaling and may improve the body’s sensitivity to insulin in some cases. Benefits have been seen in individuals with metabolic syndrome, women at risk for gestational diabetes and women with PCOS.
PCOS is a syndrome that occurs when a woman’s body produces abnormally high amounts of certain hormones.
Women with PCOS are at a higher risk of several diseases and can experience infertility issues (15).
Problems with insulin sensitivity may be one of the causes of reduced fertility in women with PCOS. Since inositol may improve insulin sensitivity, it has been studied as a potential treatment ().
Studies have found that inositol may be beneficial for improving the function of the ovaries and fertility in women with PCOS (, , ).
These studies have typically used doses of 2–4 grams per day, and benefits have been seen in normal-weight, overweight and obese women.
Overall, research has found that inositol supplements may improve menstrual cycle regularity, ovulation and pregnancy rates in women with PCOS (, , ).
Summary Inositol is a promising compound to improve several aspects of reproductive function in women with PCOS, including menstrual cycle regularity, ovulation and fertility. Doses for these purposes are typically 2–4 grams per day.
Due to its effects on neurotransmitters in the brain, inositol has been explored as a treatment for depression.
Some research has shown that 12 grams of inositol per day taken for four weeks can reduce symptoms of depression relative to a placebo ().
Another small study reported that 6 grams per day improved depression in 9 of 11 participants (23).
However, other research has shown that adding inositol to standard medication for depression does not improve symptoms more than the medication alone ().
What’s more, inositol has not proven effective in reducing depression in those who previously failed to respond to standard medication ().
Summary Though some research has shown reductions in depression with inositol, the results are mixed. Inositol may not improve symptoms in those taking medication or those who don’t respond to standard medication.
Inositol is found naturally in your body and in a variety of foods.
The quantity obtained from food can vary from less than 1 gram up to several grams, depending on the composition of your diet ().
Even when given as a dietary supplement, it has a very good safety record.
In research studies, doses have ranged from about 2 to 18 grams per day (, ).
At higher doses of 12–18 grams, some mild side effects have been reported. These primarily consist of stomach pains, upset stomach and flatulence (, ).
However, slightly reducing the dose of inositol appeared to improve these symptoms in some studies ().
Inositol supplements have even been given to pregnant women at doses of around 4 grams per day with no concerning effects ().
Summary Inositol is a naturally occurring compound with a good safety record. At higher doses of 12 grams or more, upset stomach may occur. However, these symptoms can be improved by reducing the dosage.
Inositol has been examined for several other health benefits, including:
- Weight loss: This supplement may cause a small degree of weight loss in women with PCOS (, ).
- Blood lipids: Some improvements in blood lipids like cholesterol have been reported (, ).
- Blood pressure: Several studies have reported small reductions in blood pressure in women with PCOS (, ).
Though there may be other health effects of inositol, many of them currently have very limited evidence.
Summary Due to its many roles in the body, inositol may have numerous health effects, including weight loss and improvements in blood lipids or blood pressure in specific groups. Future research may identify other important effects of this molecule.
The amount normally consumed each day may range from less than 1 gram up to a few grams depending on the foods you eat ().
Though there are several forms, inositol in supplements usually refers to the molecule myo-inositol, which makes up over 90% of the inositol content in your cells (, ).
Studies of inositol supplements have used higher amounts than typically found in food, with doses of up to 18 grams per day (, ).
Doses for insulin sensitivity and fertility are usually much lower than those used for neurological conditions like anxiety disorders and depression (, ).
Summary Inositol is present in a variety of foods in fairly small quantities. There are several forms of inositol, but most supplements contain myo-inositol. Doses of inositol supplements used in studies generally range from 2 to 18 grams per day.
Inositol is a carbohydrate that is found naturally in your body and certain foods.
It plays many roles in your body, including affecting levels of neurotransmitters and the way your body handles glucose.
It may be effective in improving some anxiety disorders and your body’s sensitivity to insulin.
Additionally, inositol appears to offer several health benefits for women with polycystic ovary syndrome (PCOS), including improving menstrual function and fertility.
This molecule has a good safety record, and few adverse effects have been seen at both moderate and high doses.
Due to its many functions, future research will likely continue to investigate inositol’s significance for health and medical applications.