A few years ago, one of my patients, a retired Army Ranger, mentioned how he suffered from shooting and burning pains in his legs and feet for the last few years. Although his doctor tried several different pain medicines, none had really helped. Then one day, his feet and legs stopped hurting so much.
“The only thing I did differently that week started a new vitamin that happened to have a lot of vitamin B12. I kept expecting the pain to come back week after week, but it’s been over 6 months, and I’m still mostly pain-free. But I still take that vitamin, just in case.”
Vitamin B12 is a water-soluble B vitamin that helps your nerves stay healthy. It also helps your body make new red blood cells, which can prevent a particular type of anemia. A deficiency in vitamin B12 can manifest as fatigue, weakness, depression, or pain in your feet or hands. The most common factors that contribute to vitamin B12 deficiency are age, diet, and medicines.
According to the National Institutes of Health (NIH), vitamin B12 is found mostly in animal proteins, such as fish, meat, poultry, eggs, milk, and milk products.
Most healthy adults get enough vitamin B12 from their diet. Those who lack vitamin B12 either don’t have much animal protein in their diet or cannot absorb it very well.
Strict vegetarians may not get enough animal protein in their diet to satisfy the recommendation of 1 to 2 mcg daily of vitamin B12. Others become deficient because they cannot absorb it very well, like the elderly, those who have had gastric bypass surgery, and people who take certain medicines.
The most common cause of vitamin B12 deficiency is not able to absorb enough of it from your food. This can be due to a condition called atrophic gastritis, which affects 10-30% of the elderly. Atrophic gastritis is a decrease in the secretion of digestive juices such as gastric acid.
It interferes with the ability to absorb vitamin B12 from your food.
Gastric acid is necessary for you to absorb vitamin B12, which is usually attached to animal proteins like ground meat or chicken. Without enough stomach acid, your body can’t break down the proteins enough for the vitamin B12 to be absorbed into your body.
Most people who can absorb vitamin B12 well only require 1 or 2 mcg daily. If you are over 70, take medicine for heartburn or an ulcer, or have had gastric bypass surgery, you may need more than that. 1000-2000mcg daily of vitamin B12 as an oral or a sublingual tablet can overcome poor absorption.
Medicines that decrease stomach acid secretion contribute to poor absorption and deficiency of vitamin B12. These include acid-reducing medications such as Prilosec® (omeprazole), Prevacid® (lansoprazole), Nexium® (esomeprazole), and Protonix® (pantoprazole). Older acid-blocking medicines also impair vitamin B12 absorption, including Zantac® (ranitidine), Pepcid®, or Axid®. Metformin, a common pill for diabetes, can also interfere with your body’s ability to absorb vitamin B12.
A deficiency in vitamin B12 can show up as fatigue, weakness, depression, or pain in your feet or hands. If you are noticing these symptoms, talk to your doctor. Vitamin B12 deficiency can be detected with a blood test. Your doctor or medical provider can advise you if you need testing, which B12 supplement would be best for you, and how much.
There’s more information about vitamin B12 at the NIH website www.nih.gov.
Here are 4 Tips on Getting Enough Vitamin B12:
- Include fortified breakfast cereals in your diet if you are vegetarian or vegan.
Since vitamin B12 isn’t found in plant foods, the National Institutes of Health (NIH) suggests including fortified breakfast cereals as an alternative source of vitamin B12 if you are vegetarian or vegan.
- Stomach acid is necessary to absorb vitamin B12 from your food.
To avoid becoming deficient in vitamin B12, minimize your use of medicines that work to reduce stomach acid. Acid blockers like Prilosec® (or omeprazole), Prevacid® (or lansoprazole), and Nexium® (or esomeprazole) along with acid-reducing medicines Tagamet® (or cimetidine), Zantac® (or ranitidine), and Pepcid® (or famotidine) are all available without a prescription.
- Oral and sublingual vitamin B12 is effective and inexpensive.
Monthly vitamin B12 injections at their doctor’s office are no longer necessary with over-the-counter (OTC) oral and sublingual formulations widely available. Most people with vitamin B12 deficiency can safely take 1000-2000 mcg daily of vitamin B12 as a supplement.
- Avoid timed-release or long-acting products of vitamin B12.
Long-acting vitamin B12 products may not be absorbed as well as immediate-release forms.
