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Last modified on December 20th, 2022
Vitamin B8 is also known as inositol. While vitamin B8 (inositol) occurs naturally in some foods, including beans, grains, nuts, and fruits, it may be useful as a supplement as well.
- Vitamin B8 benefits include the control of insulin for blood sugar control
- Also known as inositol, vitamin B8 also affects dopamine and serotonin, chemical messengers that impact mood and mental health
- While we can get some B8 from the food we eat, there are advantages to taking it in supplement form
What is Vitamin B8 (Inositol)?
Vitamin B8, also known as inositol, is important for mental and physical health. It’s actually a type of sugar that provides cell structure—the B8 vitamin influences insulin and how your chemical messengers in your brain function.
While the term B8 vitamin is usually used to describe it, it’s not actually a vitamin.
In the U.S., the average diet will typically contain around one gram of inositol a day, with sources including vegetables, fresh fruit, beans, and grains. People take supplemental doses that are often much higher. For example, according to researchers, taking supplemental doses of up to 18 grams a day may have good results with minimal side effects.
One of the most compelling areas of research when it comes to inositol vitamin B8 benefits are the effects on mental health.
Inositol may balance chemicals in your brain that affect your mood, including dopamine and serotonin.
Researchers have found that in some cases people with anxiety, depression, and compulsive disorders have lower inositol levels in their brain.
While research is ongoing, some studies have indicated inositol could be an alternative way to treat mental health conditions, with fewer side effects than traditional medicines.
Research has looked at potential inositol benefits for people with panic disorder. Panic disorder is a severe type of anxiety.
In a study of 20 people with panic disorder, they either took an 18-gram inositol supplement or a traditional anxiety medicine every day for a month.
The group taking the inositol had fewer panic attacks per week than the people who took the anxiety drug.
In another four-week study, when given 12 grams of inositol per day, people had fewer and less severe panic attacks.
Research looking at the potential for the B8 vitamin to help with symptoms of depression has shown mixed results.
In one study, taking a 12-gram vitamin B8 supplement every day for a month improved depression symptoms.
There are promising early results in research looking at the effects of inositol on bipolar disorder also.
Polycystic Ovary Syndrome
Polycystic ovary syndrome (PCOS) causes hormone imbalances in females. The effects of these imbalances include infertility and irregular periods.
Other issues linked to PCOS include weight gain and high blood sugar and cholesterol levels.
Clinical studies have found the use of inositol vitamin B8 supplements may help PCOS symptoms. This is especially true when inositol is combined with folic acid. The combination of inositol and folic acid has been found to reduce cholesterol, improve insulin function, and reduce blood pressure.
The combination of the two may also help women with fertility issues ovulate.
There was one study in which four grams of inositol and 400 mcg of folic acid were given to participants each day for three months. In this study, the combination induced ovulation for 62% of women participating.
Metabolic Syndrome Risk Factors
Metabolic syndrome is a cluster of conditions that increase the risk of chronic diseases like type 2 diabetes and heart disease.
Five conditions linked to metabolic syndrome are:
- Low levels of HDL or good cholesterol
- High blood pressure
- High blood sugar
- High blood triglycerides
- Excess fat in the abdominal area
There was a clinical study spanning over a year in 80 women with metabolic syndrome. In the study, participants took two grams of inositol twice a day. It reduced their blood triglyceride levels by 34% on average.
Diabetes During Pregnancy
Some women will experience gestational diabetes or high blood sugar levels during their pregnancy. It leads to complications in around 10% of pregnancies in the U.S. each year.
Animal studies have shown inositol has a direct relationship to insulin function. Insulin regulates blood sugar.
There are limited human studies, but some evidence suggests combining four grams of Myo-inositol and 400 mcg of folic acid may help prevent gestational diabetes if taken throughout pregnancy.
Other Vitamin B8 Benefits
Other possible benefits of inositol may include:
- In preterm infants, inositol seemed to help with breathing issues resulting from underdeveloped lungs.
- In one preliminary study, a combination of folic acid and inositol helped control blood sugar in people with type 2 diabetes.
- A small study of people with obsessive-compulsive disorder (OCD) showed that 18 grams of inositol taken daily for six weeks helped reduce symptoms.
Are There Side Effects of Inositol?
If you were going to take a vitamin B8 inositol supplement, you should speak to your doctor first. This is true any time you take a new supplement.
Overall, it is thought to be a supplement with minimal side effects, and for many people, the vitamin B8 benefits far outweigh any possible side effects.
With doses of 12 grams a day or higher, some people experience mild side effects like dizziness, nausea and problems sleeping.
In currently available studies, up to four grams of inositol daily in pregnant women has been used without known side effects.
Again, no one can replace the medical advice of your doctor.
How Much Inositol Should You Take?
Since vitamin B8 inositol is a supplement, there’s not an official dosage that you should take, but based on the studies that are available right now, the following might provide some guidance:
- If you’re taking B8 for a mental health condition, you might take 12 to 18 grams once a day for four to six weeks.
- For PCOS, you could take 1.2 grams to 2 grams twice a day for six months, plus 200 mcg of folic acid.
- For metabolic syndrome, a recommendation might be two grams of inositol twice a day for a year.
- To help control blood sugar in type 2 diabetes, you might take one gram plus 400 mcg of folic acid once a day for six months.
Again, these are only recommendations based on the studies that have already been done. Speak to your doctor first.
Myo-Inositol vs. D-Chiro-Inositol
You’ll see if you choose a B8 supplement that two terms may be on the label. There’s Myo-inositol and then there’s d-chiro-inositol.
Both can help symptoms related to PCOs, and both play a role in hormonal and ovarian health. Both are needed for good health. While they are very similar to one another, they work in different ways.
The body’s natural ratio between the two is supposed to be 40:1, which is what you’ll see with many inositol supplements. There’s a 40:1 ratio of Myo-inositol to D-chiro-inositol.
Taking D-chiro-inositol independently without Myo-inositol might not be as effective for dealing with PCOS symptoms as having both. D-chiro-inositol can affect insulin sensitivity, but Myo-inositol specifically targets ovaries.
What Are Vitamin B8 Foods?
If you’d like to try to get more B8 from your diet, some of the foods that have it include:
- Citrus fruit
- Sesame seeds
- Wheat bran
- Brown rice
What is the Best Inositol Vitamin B8 Supplement on Amazon?
There are many great inositol supplements available, and the following are a few of our favorites that are available on Amazon.
- 90-day supply of inositol in powder form
- Optimal blend of Myo-inositol and D-chiro inositol
- Provides ovarian and hormonal support
- Each dose contains 2000 mg of Myo-inositol and 50 mg of d-chiro inositol
- Helps support regular menstrual cycles
- Promotes healthy insulin levels
- Only inositol supplement independently verified for accuracy and purity
- Amazon best-selling vitamin B8 supplement
- Designed with the body’s natural ratio of Myo-inositol to D-chiro-inositol which is 40:1
- According to customer reviews, it helps with fertility
- May help with facial hair and other symptoms of PCOS
- Some reviews say the product helped with hair loss from PCOS
- All-natural ingredients with no fillers or binders
- Amazon’s choice for top B8 supplement
- Provides hormonal, menstrual, and fertility support
- Mood and energy support
- Made in the United States
- No artificial flavors or sweeteners
- According to reviews, this product is effective long-term for symptoms of PCOS
- May help with hair growth
- Some reviews say it helps with weight loss