B12 for Fibromyalgia and Chronic Fatigue Syndrome

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Raw meat (chicken breast, pork chop, and beef steak)
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B vitamins are essential for energy production, protein metabolism, red blood cell formation, and central nervous system maintenance. 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 (Regland, PLoS One) of B12 injections showed a positive response, especially in those who were also taking daily folic acid supplements.


Some experts on fibromyalgia and chronic fatigue syndrome recommend at least 50 mg daily of most B vitamins, and 500 micrograms of B12. Some experimental treatment protocols use B12 injections.

Many doctors disagree with this and consider B12 injections archaic and unsupported by scientific evidence. 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.

Side Effects

It's important to note that side effects are possible and potentially dangerous even with natural substances like B vitamins.

The most common side effect of vitamin B12 is mild, temporary diarrhea. Severe side effects are also possible. You should get medical attention right away if you experience any of the following:

  • Severe allergic reactions
  • Calf pain, swelling or tenderness
  • Chest pain
  • Feel of swelling throughout the body
  • Fever, chills or a persistent sore throat
  • Irregular heartbeat
  • Muscle weakness or cramping
  • Shortness of breath
  • Unusual bruising or bleeding


You don't need a prescription for B12 supplements. They're available from most places that sell supplements.

Still, if you're considering B12 supplementation, talk to your doctor about it. (Remember that many doctors are skeptical about B12 injections and may favor different types of supplementation.) If your doctor knows about all of your treatments, he/she can give you better guidance and make sure you're not doing anything that's unsafe.

Your pharmacist is also a great resource when it comes to negative interactions between different treatments, including supplements.

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