Vitamin B8 (Inositol, cyclohexanehexol) is a sugar alcohol and isomer of glucose. As a nootropic, inositol is involved in brain cell signaling, and is a component of cell membranes.
Vitamin B8 is no longer considered a ‘true’ B-Vitamin because your body can make inositol on its own. A “true vitamin” is either essential for life and/or cannot be made by the human body. So inositol no longer qualifies.
Inositol is used in your brain as a “secondary messenger”. It facilitates communication between brain cells. All of your major neurotransmitters need inositol to relay messages.
Inositol is also a component making up the phospholipid ‘shell’ encasing each brain cell. Once again, inositol acts as a messenger of sorts by assisting in the transport of amino acids, proteins and neurotransmitters across and into the brain cell.
Inositol is a ‘group’ of 9 molecules called ‘stereoisomers’. Myo-inositol is the most abundant stereoisomer, making up 90-95% of the total free inositol in your body.
As a nootropic, Vitamin B8 (Inositol) can be used to treat panic attacks and anxiety, depression, Obsessive Compulsive Disorder (OCD), bulimia, depression in bipolar disorder and mood swings.
Vitamin B8 (Inositol) helps:
- Brain Optimization: Inositol helps boost serotonin and dopamine receptor density. Improving the effectiveness of serotonin, GABA, glutamate and dopamine neurotransmitters in your brain.
- Neurotransmitters: Inositol improves the effectiveness of major neurotransmitters in your brain. Boosting alertness, concentration, focus, motivation and memory.
- Mood: Inositol is often used along with popular antidepressant medications improving their effectiveness. Or sometimes even replacing SSRI’s in the treatment of depression, anxiety, panic attacks and OCD.
- How does Vitamin B8 (Inositol) work in the Brain?
- How things go bad
- Vitamin B8 (Inositol) to the rescue
- How does Vitamin B8 (Inositol) feel?
- The Research
- Dosage Notes
- Side Effects
- Available Forms
- Nootropics Expert Recommendation
Vitamin B8 (Inositol, cyclohexanehexol) is a sugar alcohol and isomer of glucose found in nearly all animals and plants.
Inositol is a group of 9 molecules called stereoisomers. In this article we’re talking primarily about myo-inositol which accounts for up to 95% of the inositol in your body.
Vitamin B8 is no longer considered a ‘true’ vitamin because our body makes inositol. And we can get it from most types of food.
Myo-inositol is involved in cell-signaling. In the simplest terms, myo-inositol hears from the first neuron that it’s about to fire over a neurotransmitter. And passes that information on to the receiving neuron. Not enough inositol and the neurotransmitter can’t do its job.
Inositol is one busy molecule in your body:
- Myo-inositol affects mRNA which regulates cell volume.[i]
- Phosphatidylinositol signaling pathways control signals inside and outside of brain cells.[ii]
- Inositol plays a role in DNA repair[iii]
- Inositol affects long-term potentiation[iv]
- Myo-inositol is a component of cell membranes
- Myo-inositol regulates cell metabolism
- Myo-inositol regulates cell energy consumption
How does Vitamin B8 (Inositol) work in the Brain?
Vitamin B8 (Inositol) boosts brain health and function in several ways. But two in particular stand out.
- Inositol influences neuroplasticity and neurotransmitters. Transcranial Direct Current Stimulation (tDCS) has been used to treat depression, Parkinson’s Disease, stroke and pain. But the maximum effect of tDCS in the brain was not until several minutes after treatment. Which indicates the effects of tDCS is not by direct neurotransmitter action like you would expect for example if you were using a nootropic.[v]
Researchers concluded the effect of tDCS was best explained by the activation of a ‘secondary messenger system’, and modulation of brain cell membrane proteins.
Neurotransmitters, neuromodulators and hormones have been shown to exert their action via an intracellular (inside the cell) secondary messenger system in which the activated neuroreceptor stimulates the turnover of inositol phospholipids.[vi]
Clinical studies have found that low levels of inositol are present in patients with anorexia, brain disorders and depression.[vii] And abnormal levels of myo-inositol in middle-aged adults can signal the initial stages of cognitive decline such as Alzheimer’s and dementia.[viii]
- Inositol helps reduce anxiety and depression. Long-term potentiation needed for encoding long-term memories, and long-term depression, rely on neural signal transmission and synaptic plasticity. And both are strongly influenced by the myo-inositol and phosphoinositide pathway.[ix]
A meta-analysis and systematic review of clinical studies were evaluated comparing inositol for depression and anxiety disorders. The researchers concluded that inositol was beneficial for treating depression and anxiety.[x]
How things go bad
Inositol is an important component of brain cell membranes. And is critical as a secondary messenger for both intra- and extra-cellular signaling.
Low inositol levels have been found in those with major depressive disorder, Alzheimer’s, Parkinson’s and other neurodegenerative diseases. Science does not yet know if low inositol is a result of, or contributes to these diseases.
↓ Inositol levels decline
↓ Anxiety and depression get worse
↑ LDL-cholesterol (bad) and triglycerides increase
↓ HDL-cholesterol (good) levels decline
↑ Inflammation and oxidative stress damage neurons
Vitamin B8 supplementation can help increase the density of serotonin and dopamine receptors in your brain. And improve neurotransmitter signaling. Helping you to cope with stress, lessen depression and improve memory.
Vitamin B8 (Inositol) to the rescue
Myo-inositol enhances serotonin neuroreceptor sensitivity.[xi] And several studies have proposed a SSRI-like role for myo-inositol. Researchers believe inositol works as a SSRI because it is a secondary messenger of serotonin.
In other words, inositol gets a message from the 1st neuron that says it wants to send over a serotonin molecule. Inositol picks up that message and lets the receiving neuroreceptor know there’s an incoming serotonin molecule. Serotonin signaling is fixed and depression goes away.[xii]
As a secondary messenger, inositol is an integral part of neuroplasticity and neurotransmitter signaling. Affecting anxiety, alertness, concentration, cognition, depression and all forms of memory.
A large percentage of patients do not respond to SSRI’s when used to treat depression or anxiety. The problem could be depression not related to serotonin or GABA deficiency (they could have a dopamine problem instead).
But if it is serotonin-related depression and there is no response to SSRI’s, inositol may help. Myo-inositol helps relay the messages sent and received by serotonin receptors.
Another problem with SSRI’s like lithium is Serotonin Syndrome. Too much serotonin can be released in the brain which can be toxic and deadly. Or the SSRI can deplete stores of inositol which raises serotonin levels too high.
Myo-inositol regulates blood sodium levels which helps in the maintenance of healthy myelin sheaths that protect neurons.
Inositol can relieve anxiety and Obsessive-Compulsive Disorder (OCD). Myo-inositol can reduce panic attacks. And inositol can reduce mood swings.
Studies show that inositol is as effective as SSRI’s in treating the symptoms of bulimia and binge eating.[xvi]
Inositol can protect against lung cancer caused by smoking.[xvii]
Myo-inositol increases sperm concentration, total sperm count, decreases follicle stimulating hormone and luteinizing hormone in infertile males.[xviii]
Myo-inositol can help lower LDL-cholesterol (bad-cholesterol), C-reactive protein and blood glucose levels while increasing HDL-cholesterol (good cholesterol).[xix]
Inositol reduces inflammation. Phosphatidylinositol reduces pro-inflammatory cytokines.[xx] And D-chiro-inositol decreases the mRNA expression and secretion of tumor necrosis factor-α, interleukin 6 (IL-6).[xxi]
D-chiro-inositol has anti-aging properties and can extend lifespan.[xxii]
The bottom-line is inositol is a potent pseudo-vitamin and can be a great compliment to any nootropic stack.
How does Vitamin B8 (Inositol) feel?
Inositol increases serotonin and dopamine receptor densities. So damage that you may have done to dopamine receptors are repaired (particularly an issue with ADHD stimulant meds). And serotonin is simply more effective. Anxiety decreases, motivation goes up and depression goes away.
Inositol is great for social occasions because anxiety levels decrease. In fact, inositol outperformed fluoxetine (Prozac®) at reducing panic attacks and can become effective in just a few days. With no side effects.
Some neurohackers feel that supplementing with inositol is the best anti-depressant they’ve every used. The real beauty of inositol is you can safely combine it with the current antidepressant (i.e. SSRI) medication you currently take. Your antidepressant meds may work better!
Inositol is a proven remedy for treating the symptoms of Obsessive-Compulsive Disorder (OCD). You should feel a noticeable reduction in negative thoughts. Some things just won’t bother you as much. And won’t dominate your thoughts so easily.
And inositol is an effective method of taming panic attacks.
Inositol to Treat Panic Attacks
Estimates are that only about 70% of patients respond to standard drug treatments for panic disorder. And many often discontinue the drugs because of negative side effects.
Israeli researchers decided to compare inositol with the SSRI fluvoxamine (Luvox®) for panic disorder. In this double-blind, controlled, random-order crossover study 20 patients completed 1 month of 18 grams per day of inositol and 1 month of 150 mg per day of fluvoxamine.
In the first month, inositol reduced the number of panic attacks per week by 4 compared to only 2.4 for fluvoxamine. Nausea and fatigue were noted with those using Luvox® but not with inositol.
The natural compound inositol was more effective than a SSRI for treating panic disorder.[xxiii]
Vitamin B8 (Inositol) for Depression
A study published in the American Journal of Psychiatry noted that levels of inositol in depressed patients were lower than normal. In this trial, the authors administered 12 grams per day of inositol or a placebo to depressed patients for 4 weeks.
The overall improvement in depression scores was significantly greater than placebo by week 4. And no side effects were noted.
The researchers commented that “this is the first time a precursor strategy for a secondary messenger rather a neurotransmitter” was used in treating depression.
The authors concluded that “inositol had a significant antidepressant effect”.[xxiv]
Another study tried using inositol to treat Premenstrual Dysphoric Disorder (PMDD). PMDD is a particularly nasty form of PMS. It’s a condition in which a woman has severe depression, irritability and tension before menstruation.
Scientists don’t really know what causes PMDD except it has something to do with serotonin. Serotonin is the “calming neurotransmitter”. When it fails for any reason you get depressed, irritable, obsessive, negative and worried.
In this 2-phase clinical trial, PMDD patients were given myo-inositol in powder form, or a soft-gel capsule equivalent to 2 grams of myo-inositol.
The results showed a significant improvement on 3 different scales of measuring depression. Inositol significantly improved PMDD and associated depression, irritability and tension.[xxv]
Vitamin B8 (Inositol) for OCD
Inositol is good for treating Obsessive-Compulsive Disorder (OCD). OCD is a type of anxiety characterized by unwanted, recurring thoughts and behaviors.
One double-blind, controlled crossover trial treated 13 OCD patients with 18 grams per day of inositol for 6 weeks.
The OCD patients had significantly lower scores on the Yale-Brown Obsessive Compulsive Scale when taking inositol than when taking placebo.
The authors concluded that “inositol is effective in depression, panic, and obsessive-compulsive disorder, a spectrum of disorders responsive to selective serotonin reuptake inhibitors (SSRI’s)”.[xxvi]
Clinically effective dosage for depression and anxiety is up to 12 grams per day. Split your dose into 3-times per day. 4 grams in the morning, 4 grams at noon and 4 grams prior to bedtime.
Clinically effective dosage for OCD is up to 18 grams per day. Split into 3 equal doses of 6 grams each.
The clinical dosages mentioned here are the ones used in clinical trials. Most people experienced relief of symptoms within 3 months. Some people showed improvements within a week or sooner.
Important note: It may not be necessary for you to go as high as 12 or 18 grams per day. Inositol could be just as effective for you in much smaller doses.
Most neurohackers notice benefits when taking 3 – 4 grams per day or less.
Vitamin B8 (Inositol) is non-toxic. So is considered well-tolerated and safe.
Higher doses like those used in clinical trials could result in flatulence, stomach upset, nausea, diarrhea, increased mood swings for bipolar or psychosis patients.
If you’ve been diagnosed with bipolar or bipolar-spectrum disorder, please consult a pharmacist or your doctor before using inositol.
Studies have shown and neurohackers verify that inositol supplementation may reduce testosterone levels and libido. Most of the Low-T reports were by woman but I’ve heard a few men reporting Low-T and libido from inositol as well.
Inositol is available in capsules, softgels, and in powder form.
Inositol powder is the least expensive way to supplement with this nootropic. Inositol is basically a sugar so it tastes sweet. Not as sweet as sugar but it tastes good on its own. Or mixed in your favorite beverage.
Lecithin is comprised of both inositol and choline. So lecithin as a supplement will provide you with inositol.
Inositol is often supplied by supplement manufacturers as “inositol + choline”. The thinking behind this combined supplement is that inositol compliments the effects of choline.
When inositol and choline are used together, they are supposed to improve nerve function and help you metabolize cholesterol.
But high doses of choline can leave you depressed and sleepy. So if you want to add inositol to your nootropic stack, I suggest you avoid the combination and go with straight inositol.
Nootropics Expert Recommendation
Vitamin B8 (Inositol) up to 3 grams per day
We recommend using Vitamin B8 (Inositol) as a nootropic supplement.
Your body does make Vitamin B8 on its own. And you get it from food. So it is unlikely that you are inositol deficient. But if you want to try inositol for its anti-anxiety and antidepressant benefits, you must take it as a supplement.
Inositol is especially helpful for those suffering from anxiety, depression, panic attacks, or OCD.
Experience shows Inositol helps stop and reverse the symptoms associated with high cholesterol levels. B8 will lower ‘bad’ LDL-cholesterol as well as raise ‘good” HDL-cholesterol.
Vitamin B8 is also particularly helpful to quell anxiety caused by social situations.
Vitamin B8 can help you get a good night’s sleep. Many find it more effective than sleep meds and other nootropics used for sleep. You’ll awaken feeling refreshed and calm. Ready to start your day.
The recommended dosage of Vitamin B8 (Inositol) is up to 3 grams per day. But start at a gram or less, and work your way up depending on how you feel. Clinical doses of 12 or 18 gram are usually not needed for most people.
[i] Wiese T.J., Dunlap J.A., Conner C.E., Grzybowski J.A., Lowe W.L. Jr., Yorek M.A. “Osmotic regulation of Na-myo-inositol cotransporter mRNA level and activity in endothelial and neural cells.” American Journal of Physiology. 1996 Apr;270(4 Pt 1):C990-7. (source)
[iii] Fisher S.K., Novak J.E., Agranoff B.W. “Inositol and higher inositol phosphates in neural tissues: homeostasis, metabolism and functional significance.” Journal of Neurochemistry. 2002 Aug;82(4):736-54. (source)
[v] Siegel G., Agranoff B., Albers R., Molinoff P. Basic neurochemistry. New York: Raven Press; 1994.
[vii] Rango M., Cogiamanian F., Marceglia S., Barberis B. “Myoinositol content in the human brain is modified by transcranial direct current stimulation in a matter of minutes: A 1H-MRS study” Magnetic Resonance in Medicine Volume 60, Issue 4 October 2008 Pages 782–789 (source)
[viii] Eagen D.E., et. Al. “Elevated Serum C-Reactive Protein Relates to Increased Cerebral Myoinositol Levels in Middle-Aged Adults” Cardiovascular Psychiatry and Neurology. 2012; 2012: 120540. (source)
[xiii] Ciranna L. “Serotonin as a Modulator of Glutamate- and GABA-Mediated Neurotransmission: Implications in Physiological Functions and in Pathology” Current Neuropharmacology. 2006 Apr; 4(2): 101–114. (source)
[xv] Herman-Sucharska I., Grzybek M., Grochowska A., Karcz P., Urbanik A. article in Polish “[Myoinositol trends in HMRS brain spectrum of patients with hepatic encephalopathy].” Przegl Lek. 2010;67(4):247-50. (source)
[xvii] Han W., et. Al. “The Chemopreventive Agent Myoinositol Inhibits Akt and Extracellular Signal-Regulated Kinase in Bronchial Lesions from Heavy Smokers” Cancer Prevention Research US National Library of Medicine 2013 Jul 18 (source)
[xviii] Calogero A.E., et. Al. “Myoinositol improves sperm parameters and serum reproductive hormones in patients with idiopathic infertility: a prospective double-blind randomized placebo-controlled study” Andrology Volume 3, Issue 3 May 2015 Pages 491–495 (source)
[xix] Maeba R., Hara H., Ishikawa H., Hayashi S., Yoshimura N., Kusano J., Takeoka Y., Yasuda D., Okazaki T., Kinoshita M., Teramoto T. “Myo-inositol treatment increases serum plasmalogens and decreases small dense LDL, particularly in hyperlipidemic subjects with metabolic syndrome.” Journal of Nutritional Science and Vitaminology (Tokyo). 2008 Jun;54(3):196-202. (source)
[xx] Inafuku M., Nagao K., Inafuku A., Yanagita T., Taira N., Toda T., Oku H. “Dietary phosphatidylinositol protects C57BL/6 mice from concanavalin A-induced liver injury by modulating immune cell functions.” Molecular Nutrition and Food Research. 2013 Sep;57(9):1671-9 (source)
[xxi] Fortis-Barrera Á., Alarcón-Aguilar F.J., Banderas-Dorantes T., Díaz-Flores M., Román-Ramos R., Cruz M., García-Macedo R. “Cucurbita ficifolia Bouché (Cucurbitaceae) and D-chiro-inositol modulate the redox state and inflammation in 3T3-L1 adipocytes.” Journal of Pharmacy and Pharmacology. 2013 Oct;65(10):1563-76 (source)
[xxii] Hada B., Yoo M.R., Seong K.M., Jin Y.W., Myeong H.K., Min K.J. “D-chiro-inositol and pinitol extend the life span of Drosophila melanogaster.” Journal of Gerontology. Series A, Biological Sciences and Medical Sciences. 2013 Mar;68(3):226-34. (source)
[xxiii] Palatnik A., Frolov K., Fux M., Benjamin J. “Double-blind, controlled, crossover trial of inositol versus fluvoxamine for the treatment of panic disorder.” Journal of Clinical Psychopharmacology. 2001 Jun;21(3):335-9. (source)
[xxiv] Levine J., Barak Y., Gonzalves M., Szor H., Elizur A., Kofman O., Belmaker R.H. “Double-blind, controlled trial of inositol treatment of depression.” American Journal of Psychiatry. 1995 May;152(5):792-4. (source)
[xxv] Carlomagno G., Unfer F., Buffo S., D’Ambrosio F. “Myo-inositol in the treatment of premenstrual dysphoric disorder” Human Psychopharmacology Volume 26, Issue 7 October 2011 Pages 526–530 (source)