B12 deficiency can result in persistent fatigue, weakness, and slowing metabolism which can lead to weight gain
The good news is that finding a B12 deficiency is relatively simple
Some fortified foods, dietary supplements, and medications contain a synthetic version of vitamin B12
If the patient is pregnant or breastfeeding, inform the prescriber usually, injections continue as needed, and B even passes into breast milk (beneficial)
Research suggests this may be due to higher concentrations of beta-3 adrenergic receptors in these fat depots
however, cases of hypercobalaminemia in leukemia, autoimmune diseases, and pulmonary and renal dysfunction have also been observed (Andrs et al., 2013