Women health and microbiota:Different aspects of well-being

In this editorial,we comment on the article by Marano et al recently published in the World Journal of Gastroenterology 2023;29(45):5945-5952.We focus on the role of gut microbiota(GM)in women’s health,highlighting the need to thoroughly comprehend the sex differences in microbiota.Together,the host and GM support the host’s health.The microbiota components consist of viruses,bacteria,fungi,and archaea.This complex is an essential part of the host and is involved in neu-rological development,metabolic control,immune system dynamics,and host dynamic homeostasis.It has been shown that differences in the GM of males and females can contribute to chronic diseases,such as gastrointestinal,metabolic,neurological,cardiovascular,and respiratory illnesses.These differences can also result in some sex-specific changes in immunity.Every day,research on GM reveals new and more expansive frontiers,offering a wealth of innovative oppor-tunities for preventive and precision medicine.

Long-term metformin therapy and vitamin B12 deficiency: An association to bear in mind

To date,metformin remains the first-line oral glucose-lowering drug used for the treatment of type 2 diabetes thanks to its well-established long-term safety and efficacy profile.Indeed,metformin is the most widely used oral insulinsensitizing agent,being prescribed to more than 100 million people worldwide,including patients with prediabetes,insulin resistance,and polycystic ovary syndrome.However,over the last decades several observational studies and meta-analyses have reported a significant association between long-term metformin therapy and an increased prevalence of vitamin B12 deficiency.Of note,evidence suggests that long-term and high-dose metformin therapy impairs vitamin B12 status.Vitamin B12(also referred to as cobalamin)is a water-soluble vitamin that is mainly obtained from animal-sourced foods.At the cellular level,vitamin B12 acts as a cofactor for enzymes that play a critical role in DNA synthesis and neuroprotection.Thus,vitamin B12 deficiency can lead to a number of clinical consequences that include hematologic abnormalities(e.g.,megaloblastic anemia and formation of hypersegmented neutrophils),progressive axonal demyelination and peripheral neuropathy.Nevertheless,no definite guidelines are currently available for vitamin B12 deficiency screening in patients on metformin therapy,and vitamin B12 deficiency remains frequently unrecognized in such individuals.Therefore,in this“field of vision”article we propose a list of criteria for a cost-effective vitamin B12 deficiency screening in metformin-treated patients,which could serve as a practical guide for identifying individuals at high risk for this condition.Moreover,we discuss additional relevant topics related to this field,including:(1)The lack of consensus about the exact definition of vitamin B12 deficiency;(2)The definition of reliable biomarkers of vitamin B12 status;(3)Causes of vitamin B12 deficiency other than metformin therapy that should be identified promptly in metformin-treated patients for a proper differential diagnosis;and(4)Potential pathophysiological mechanisms underlying metformin-induced vitamin B12 deficiency.Finally,we briefly review basic concepts related to vitamin B12 supplementation for the treatment of vitamin B12 deficiency,particularly when this condition is induced by metformin.