Your metabolism gets what it needs to get better energy from what you eat
Regarding the form of vitamin B12 used, cyanocobalamin was the most common (n = 14), followed by methylcobalamin (n = 6), hydroxocobalamin (n = 4), and combinations including adenosylcobalamin in isolated cases

deficiency (more common in those following plant-based diets or with malabsorption) can cause palpitations and fatigue, primarily through anaemia [2] [3] Vitamin D some observational studies have suggested a possible association between low vitamin D and cardiac arrhythmias, though the evidence remains preliminary and no causal link has been established [20] [21] Calcium severe hypocalcaemia can affect cardiac muscle function, though this is rarely caused by dietary restriction alone and usually reflects an underlying medical condition If you are concerned about nutritional deficiencies, your GP can arrange appropriate blood tests, which may include a full blood count (FBC), ferritin, vitamin B12 and folate, and urea and electrolytes (U&Es), with magnesium and calcium checked if clinically indicated
Storage in clear or translucent containers exposed to direct sunlight is documented to shorten the effective window