If you have type 2 diabetes, your chances of developing vitamin B12 deficiency are greater than those of non-diabetics. That’s because metformin, a popular drug for diabetes interferes with vitamin B12 absorption, causing severe B12 deficiency. Other causes of vitamin B12 deficiency include pernicious anemia, bariatric surgery, and gastrointestinal disorders.
Vitamin B12- Cobalamin
Vitamin B12 is a water-soluble nutrient that occurs naturally in protein-based foods, including beef, chicken, fish, eggs, milk, and cheese. It is one of a group of B vitamins (B complex). Vitamin B12 performs many crucial functions for your body:
- Vitamin B12 aids in producing red blood cells
- Vitamin B12 protects your nervous system
- Vitamin B12 is required for DNA synthesis
- Vitamin B12 lowers homocysteine levels, thus reducing your risk for heart attack and stroke
- Vitamin B12 helps your body convert fat to energy
Metformin- its effect on B12 levels
Metformin, a hypoglycemic drug for treating type 2 diabetes, interferes with your body’s ability to digest vitamin B12. According to numerous studies, up to 30% of diabetics who take metformin suffer the effects of vitamin B12 deficiency.
Researchers believe that metformin may hinder the production of intrinsic factor, a protein your body uses to grab vitamin B12 from food sources and absorb it into the bloodstream.
Other suggestions for metformin’s link with B12 deficiency include possible bacterial overgrowth and hindered movement of the small intestines.
How much vitamin B12 do you need?
The Recommended Dietary Allowance (RDA) for vitamin B12 varies by age, and applies to healthy individuals:
- Infants: .4 mcg to .5 mcg
- Toddlers: .9 mcg
- Children, 4-8 yrs. of age: 1.2 mcg
- Children, 9-13 yrs. of age: 1.8 mcg
- Adult males: 2.4 mcg
- Adult females (not pregnant or lactating): 2.4 mcg
- Pregnant females: 2.6 mcg
- Lactating females: 2.8 mcg
People suffering from chronic illness may opt to take much higher doses.
People who benefit from larger doses of vitamin B12 include:
- Elderly individuals
- People with pernicious anemia
- People taking proton pump inhibitors for acid reflux or stomach ulcers
- People with gastrointestinal disorders like Crohn’s disease or Celiac disease
- Diabetics taking metformin
Diabetics need even more B12
According to a recent 7-year survey, type 2 diabetics taking metformin may require higher doses of vitamin B12 than originally believed in order to avoid vitamin B12 deficiency, as the current RDA (2.5 mcg) is not sufficient.
- Of the survey participants who took metformin for type 2 diabetes, 5.8% had vitamin B12 deficiency- low B12 levels in the blood.
- Only 2.4% of diabetics not taking metformin had low levels of vitamin B12.
- About 3.3% of test subjects who did not have diabetes showed signs of vitamin B12 deficiency.
- For diabetics, taking oral vitamin B12 supplements did not affect their B12 levels, nor did it affect the symptoms of vitamin B12 deficiency.
- When intestinal disorders interfere with B12 absorption, the only other method for supplementing vitamin B12 is directly through the bloodstream.
Do you have vitamin B12 deficiency?
Vitamin B12 deficiency is diagnosed through blood testing. However, many of the signs of B12 deficiency may be masked by other prevailing ailments, so it’s important to know the symptoms.
Symptoms of vitamin B12 deficiency include:
- Chronic fatigue
- Memory loss
- Aggressive behavior
- Mental confusion, “brain fog”
- Difficulty concentrating
- Painful numbness in hand and feet, “tingling” sensations
- Poor motor coordination
- Clumsiness, stumbling
- Sore tongue
- Altered taste perception
- Eye twitches
Untreated, vitamin B12 deficiency could result in severe nerve damage, early-onset dementia, increased risk for heart attack and stroke, and death.
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