By Leslie Vandever
When it comes to treating type 2 diabetes, metformin is the most widely used and effective drug in the world. It was first approved for use in the U.S. in 1995. Metformin helps keep blood glucose (sugar) levels under control. It makes the liver, muscle, fat and cells more sensitive to the insulin made by your body. It also decreases the amount of glucose you absorb from your food and the amount made by your liver.
Metformin can cause vitamin B12 (cobalamin) deficiency in older patients, patients taking higher doses and patients that have been taking it for a long time.
A vitamin B12 deficiency can be serious. Vitamin B12 is an essential micronutrient that’s needed for DNA synthesis, nerve and brain function and cellular repair. And, without it, your body can’t make red blood cells, which carry oxygen throughout the body. If you’re B12 deficient, you may become anemic.
Metformin can also—very rarely—cause lactic acidosis, which can be fatal.
The average adult needs 2.4 micrograms of vitamin B12 per day and it can’t be made in the body. Instead, it comes from the animal foods you eat, like meat, dairy products, eggs and seafood. Vegetarians and vegans are more likely to become vitamin B12 deficient if they don’t eat grains that have been fortified with B12 or take supplements. People who take proton pump inhibiting medications, like Nexium or Prevacid, or an H2 blocker, like Pepcid or Zantac, may also become vitamin B12 deficient.
As we grow older (over 50) we’re more prone to a vitamin B12 deficiency because of age-related problems with absorption from the gastrointestinal tract.
Symptoms of vitamin B12 deficiency are generally slow to develop, but they intensify over time. They may include:
- Trouble thinking (cognitive difficulties)
- Memory loss
- Tingling, numbness or strange sensations in the hands, legs or feet (neuropathy)
- Swollen tongue
- Paranoia or hallucinations
Some damage, particularly to the nerves, can’t be reversed.
A blood test is the surest way to find out if you’re vitamin B12 deficient. A serious deficiency can be treated with weekly B12 injections and/or supplements. But the best way to be sure you won’t become vitamin B12 deficient is to take a daily multivitamin.
For more information about diabetes, vitamins and other health issues, visit HealthLine.
Leslie Vandever is a professional journalist and freelance writer. Under the pen-name “Wren,” she also writes a blog about living well with rheumatoid arthritis called RheumaBlog. In her spare time, Vandever enjoys cooking, reading and working on the Great American Novel.
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