myo-Inositol is important for thyroid hormone synthesis. [32] Depletion of myo-inositol may predispose to development of hypothyroidism. [32] Patients with hypothyroidism have a higher demand for myo-inositol than healthy subjects. [32] Inositol, primarily the isomer myo-inositol, is a carbocyclic sugar that is abundant in the brain and other mammalian tissues; it mediates cell signal transduction in response to a variety of hormones, neurotransmitters, and growth factors and participates in osmoregulation. [2] Concerning regulation of osmosis, in most mammalian cells the intracellular concentrations of myo-inositol are 5 to 500times greater than the extracellular concentrations. [3] https://www.mayoclinic.org/healthy-lifestyle/weight-loss/expert-answers/vitamin-b12-injections/faq-20058145 Kim J, et al. (2019). Association between metformin dose and vitamin B12 deficiency in patients with type 2 diabetes.

Inositol affects the processes that make neurotransmitters, the molecules responsible for relaying information within your brain ( 1). Saito, T. [Choline antagonists and antacids for the treatment of peptic ulcer]. Nippon Rinsho 1984;42(1):158-162. View abstract. It is a sugar alcohol with half the sweetness of sucrose (table sugar). Inositol was once considered to be a Bvitamin before the discovery that it is made naturally in the human body from glucose, and therefore cannot be a vitamin. A human kidney makes about two grams per day. Other tissues synthesize it too, and the highest concentration is in the brain, where it plays an important role in making other neurotransmitters and some steroid hormones bind to their receptors. [4]Researchers have examined whether inositol supplements can improve symptoms associated with conditions affecting serotonin and the brain. People use inositol for many different health conditions. Research has shown that the supplement may help with the following: Metabolic syndrome Some research also indications that taking too much choline increases your risk of heart disease. What are the best choline supplements? In a year-long clinical study in 80 women with metabolic syndrome, 2 grams of inositol taken twice daily reduced blood triglyceride levels by an average 34% and total cholesterol by 22%. Improvements in blood pressure and blood sugar were also seen ( 24).

Gelenberg, A. J., Wojcik, J., Falk, W. E., Bellinghausen, B., and Joseph, A. B. CDP-choline for the treatment of tardive dyskinesia: a small negative series. Compr.Psychiatry 1989;30(1):1-4. View abstract. Brady, S.; Siegel, G.; Albers, R. W.; Price, D. (2005). Basic Neurochemistry: Molecular, Cellular and Medical Aspects. Academic Press. p.348. ISBN 9780080472072. Covington TR, et al. Handbook of Nonprescription Drugs. 11th ed. Washing Noteworthy, current practice guidelines, which however produced many controversies, restrict the use of levothyroxine in the SCH to patients with overt hypothyroidism and TSH >10 mIU/mL. Indeed, one of the most critical problems related to SCH management, is the over treatment even in those patients for which it is not necessary. Pharmacological treatment of SCH is recommended only in particular cases, such as women seeking pregnancy and patients with important comorbidities ( 38, 43, 44), and it should be tailored to the individual patient based on the exposure at specific risk factors. Myo-InositolKukuljan, M.; Vergara, L.; Stojilković, S. S. (February 1997). "Modulation of the kinetics of inositol 1,4,5-trisphosphate-induced [Ca 2+]i oscillations by calcium entry in pituitary gonadotrophs". Biophysical Journal. 72 (2 Pt 1): 698–707. Bibcode: 1997BpJ....72..698K. doi: 10.1016/S0006-3495(97)78706-X. PMC 1185595. PMID 9017197. If you’re not sure which vitamin B is best for your needs, Nordic Naturals Vitamin B Complex might be a good option, as it provides all eight B vitamins in highly absorbable forms. What is the best B vitamin for anxiety? myo-Inositol is naturally present in a variety of foods, although tables of food composition do not always distinguish between lecithin, the relatively bioavailable lipid form and the biounavailable phytate/phosphate form. [6] Foods containing the highest concentrations of myo-inositol and its compounds include fruits, beans, grains, and nuts. [6] Fruits in particular, especially oranges and cantaloupe, contain the highest amounts of myo-inositol. [53] It is also present in beans, nuts, and grains, however, these contain large amounts of myo-inositol in the phytate form, which is not bioavailable without transformation by phytase enzymes. Bacillus subtilis, the microorganism which produces the fermented food natto, produces phytase enzymes that may convert phytic acid to a more bioavailable form of inositol polyphosphate in the gut. [54] Additionally, Bacteroides species in the gut secrete vesicles containing an active enzyme which converts the phytate molecule into bioavailable phosphorus and inositol polyphosphate, which is an important signaling molecule in the human body. [55] Other studies assessed the efficacy of MYO in patients with SCH and HT, depending on the duration of the treatment, and found that MYO+Se supplementation reduced TSH by 21% in three months ( 69). TSH decreased further, and linearly, when treatment duration was extended up to 1 year ( 62). a b Carlomagno, G.; Unfer, V.; Roseff, S. (2011). "The D- chiro-inositol paradox in the ovary". Fertility and Sterility. 95 (8): 2515–6. doi: 10.1016/j.fertnstert.2011.05.027. PMID 21641593.

Buchman AL, Dubin MD, Moukarzel AA, et al. Choline deficiency: a cause of hepatic steatosis during parenteral nutrition that can be reversed with intravenous choline supplementation. Hepatology 1995;22:1399-403. View abstract. Lu L, Ni J Zhou T Xu W Fenech M Wang X. Choline and/or Folic Acid Deficiency is Associated with Genomic Damage and Cell Death in Human Lymphocytes In Vitro. Nutr Cancer. 2012;64(3):481-487.

Amazingly, 20% of the women taking inositol supplements no longer met the criteria for metabolic syndrome by the end of the study ( 24). Summary Isabella, R.; Raffone, E. (2012). "Does ovary need D- chiro-inositol?". Journal of Ovarian Research. 5 (1): 14. doi: 10.1186/1757-2215-5-14. PMC 3447676. PMID 22587479. myo-Inositol can also be found as an ingredient in energy drinks, [56] either in conjunction with or as a substitute for glucose. [57] Recent preliminary metabolomic investigations compared histological thyroid samples of healthy subjects with those of patients with non-malignant nodular diseases, follicular adenoma and thyroid carcinoma, focusing on the potential role of MYO in thyroid nodules. The authors concluded that MYO reduction correlates with increased thyroidal tissue malignancy. The study identified MYO and scyllo-inositol as possible markers for thyroid malignancy ( 74). A subsequent retrospective study examined the effects of 600 mg MYO supplementation for 6 months on benign nodules [class I and II according to the AACE/ACE/AME Guidelines that outline the risk of malignancy of thyroid lesions ( 75)] in patients with SCH and HT. The authors found significantly positive results regarding diameter reduction (16.72 ± 1.32 vs 12.44 ± 1.81), number of mixed nodules for patients (1.39 ± 0.16 vs 1.05 ± 0.15) and elasticity (1.80 ± 0.13 vs 1.24 ± 0.18) ( 76). Conclusion