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While rare, some experts suggest long-term use could impact zinc levelsconsult your doctor to monitor micronutrient status

and patients with pernicious anemia who have optic neuropathy COBALAMIN (Vitamin B12) Deficiency Causes Vegetarians (dietary deficiency) Older adults: atrophic gastritis affects 10% 30% and leads to decrease in hydrochloric acid secretion in the stomach and decreased absorption of Vitamin B12 The liver can store up to six years worth of Vitamin B12 so deficiencies are rare Effects of deficiency Megaloblastic anaemia (pernicious anaemia) Progressive demyelination of nerve cells Elevation in levels of circulating homocysteine that leads to production of defective collagen and elastin with a negative impact on arteries, bone and skin Deep vein thrombosis is associated with homocysteinemia that causes the activation of the intrinsic coagulation cascade Symptoms include fatigue, weakness, constipation, loss of appetite and weight loss Numbness, tingling of the feet imbalance, depression, confusion, dementia, poor memory and glossitis

There is evidence on its ability to mediate carnitine and acetylcarnitine transport albeit with a very low affinity (Pochini et al., 2011, 2016) since carnitine is not its main substrate
DOI: 10.7759/cureus.29696
Rho GTPase signaling at the synapse: implications for intellectual disability