Two articles from the 1990s, recounting in vitro experiments, showed that NT was a potent constrictor of airway muscles [23,24], while a later study showed the opposite effect in the form of NT-mediated inhibition of guinea pig cholinergic and noncholinergic bronchial ring contraction evoked by electrical field stimulation [25]
Despite its evocative name, its precise mechanism remains incompletely understood, which is exactly what makes it an enduring subject of experimental investigation into sleep, stress and neuroprotection
Too many people expect dramatic results in the first week and interpret gradual onset as failure
Groups at higher risk of deficiency include older adults (due to reduced stomach acid production), people following vegan or strict vegetarian diets (as B12 is naturally found almost exclusively in animal products), individuals with pernicious anaemia or other malabsorption conditions, those taking certain medications such as metformin or proton pump inhibitors long-term, and people with significant nitrous oxide exposure (including recreational use), which can inactivate B12 in the body
Mismanagement risk
