B-12 (Methylcobalamin)

One of the most common nutrient deficiencies involves vitamin B-12. B-12 is a crucial nutrient for nerve health and red blood cell production.
Symptoms of B-12 deficiency might include fatigue, brain fog, weakness, slow reflexes, pale skin, and sore mouth or tongue.

Because many sources of B-12 are animal-derived, vegetarians and vegans may be particularly at risk for having low levels of B-12. In addition, those individuals who lack the ability to effectively absorb this vitamin, simply don’t reap the benefits, even if they are eating foods rich in B-12.

Many individuals choose to get injections of methylated B-12 (the active form), bypassing the digestive system all together.