By Adrienne Dellwo 
Medically reviewed by David Ozeri, MD
September 25, 2020

B vitamins are essential for energy production, protein metabolism, red blood cell formation, and central nervous system maintenance.1 B vitamins are water soluble, meaning that your body uses what it can and eliminates the rest through urine.

B12 is a common supplement for increasing energy. It's available in several forms, including injections, tablets, and sublingual (under the tongue) forms.

A few (but limited) studies suggest that low B12 levels may be involved in fibromyalgia and chronic fatigue syndrome. If so, it's possible that they are, at least in part, responsible for the low energy levels typical of both conditions.

Research on B12 supplements for these illness has just begun, but what little we have is promising. A 2015 study of B12 injections showed a positive response, especially in those who were also taking daily folic acid supplements.2

Many doctors disagree with this and consider B12 injections archaic and unsupported by scientific evidence.3 Some doctors and researchers, however, say anecdotal evidence supports B12 supplements for achieving and maintaining higher B12 levels in people with these conditions.

Dietary Sources

B12 is readily available in almost any animal-derived food, such as:

  • Beef liver & other organ meats
  • Shellfish
  • Meat & poultry
  • Eggs
  • Milk & other dairy products
  • Fortified breakfast cereals
  • Nutritional yeast

Some vegetarian and vegan products are fortified with B12 since a plant-based diet generally will not contain enough. If you're on a special diet, you may want to talk to your doctor and/or a nutritionist about how to best get enough important vitamins and minerals.