This Common Diabetes Drug Can Cause A Vitamin B12 Deficiency – 7 Signs And What To Do About It
POSTED ON August 9, 2018 BY Emilyn Gil

We live in an incredible age where modern medicine is at its finest and improving every day. This means that things such as medical assistance, treatments, and medications are more widely available to a larger part of the world’s population.
What many people don’t know is that while a medication may be assisting your health in one aspect, it may have side effects that are harming you in another aspect. One example is a diabetes drug that can cause vitamin B12 deficiency.
What Is Vitamin B12?
Vitamin B12 is an essential vitamin that your body needs, but can’t make for itself. This is why it’s important to add foods that contain vitamin B12 to your diet, or to provide this vitamin to your body as a supplement.
Your body needs vitamin B12 in order to properly form red blood cells, perform DNA synthesis, and keep your neurological system functioning properly. In other words, it’s basically needed in every part of your body! (1)
The Drug That Causes Vitamin B12 Deficiency
While there are several drugs known to cause vitamin B12 deficiency (such as chloramphenicol, omeprazole, lansoprazole and histamine H2), recent research has shown significant deficiency results with metformin, a drug used to treat diabetes. (2, 3)
Researchers from Albert Einstein College of Medicine found that those who used metaformin, especially for a long period of time, were twice as likely to become deficient in vitamin B12 than those not on the medication. (4)
If you are taking metaformin, it’s important that you speak to your doctor about getting checked for vitamin B12 deficiency and ensure that you are getting enough into your system.
What Does Deficiency Mean For You?
Even if you aren’t taking this or another medication that affects your levels of vitamin B12, it’s important to know the signs of deficiency. Studies have shown that up to 15% of the general population is deficient in this vitamin. That could be you! (1)
How Do I Know If I’m Deficient In Vitamin B12?
Here are 7 common signs that you may be deficient in vitamin B12:
1. Anemia
Anemia occurs when your blood has a low number of red blood cells. Since vitamin B12 is essential for forming red blood cells, you are at risk for anemia without it. (5)
2. Fatigue And Weakness
Vitamin B12 has a role in energy metabolism, meaning it can help enhance your energy and performance. A deficiency in this vitamin may cause you to feel weak and fatigued. (6)
3. Constipation
Vitamin B12 also plays a large role in the gastrointestinal system. Constipation can often be a sign of a deficiency. (2)
4. Loss Of Appetite And Weight Loss
Not getting enough vitamin B12 in your diet can cause you to lose your appetite and in turn, lose an unhealthy amount of weight. (1)
5. Loss Of Balance
Becoming weak, fatigued and anemic can also cause a significant loss of balance. Keeping your vitamin B12 at a healthy level can prevent this. (1)
6. Confusion Or Dementia
Because vitamin B12 is essential for may neurological functions, a deficiency can cause cognitive decline such as confusion or dementia. (7)
7. Depression
Vitamin B12 has been found to significantly improve depressive symptoms in patients. Keeping your vitamin B12 at a healthy level can help your mood. (8)
Where Can I Get More Vitamin B12?

While supplementing is a great option for some people, the best way to make sure you’re getting enough of this vitamin is to eat healthy foods that contain it! Some of these foods are:
- Beef
- Liver
- Eggs
- Fish
- Milk
- Yogurt
- Cheese
- Chicken
- Ham
- Clams
- Breakfast cereals fortified with vitamin B12 (check the label!) (2)
Conclusion
Keeping your vitamin B12 up is important, whether you are taking metaformin regularly or not. Try adding some of the foods from the list above to your diet to ensure that your body has the vitamin B12 it needs and to avoid those terrible symptoms of deficiency.
Resources:
- https://ods.od.nih.gov/factsheets/VitaminB12-HealthProfessional/
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4880159/
- https://academic.oup.com/jcem/article/101/4/1754/2804585
- https://www.nhlbi.nih.gov/health-topics/pernicious-anemia
- https://ods.od.nih.gov/factsheets/Vitamin%20B12-HealthProfessional/
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4341306/
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3856388/
Emilyn Gil is a 22 year old English Major at UVU. She started writing at age 6, and since then has won several awards including the Scholastic Art and Writing Gold Key and was featured in the Kolob Canyon Review in Cedar City. Aside from the written word, her other passions include performing in the occasional musical theater production, and playing piano, guitar, and ukulele. Some of her favorite pastimes are baking, napping, and spending time with family. She likes monkeys, homemade rolls, and the color yellow. She has traveled to Ecuador, Argentina, Mexico, and Canada, and currently resides in Orem, Utah with her husband Jorge. You can find more of her work online at emilyaddn.blogspot.com or on Instagram at @emilyncan.
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