Vitamin B12, an essential water-soluble vitamin, is very important for the production of red blood cells, synthesis of DNA, and normal neurological function. However, its absorption in the body is complex and depends on many factors. Many patients complain of persisting signs of vitamin B12 deficiency even after taking supplements regularly.
Thus, adequate absorption of vitamin B12 is very important in all individuals, especially at-risk groups such as vegetarians, vegans, elderly people, and others who have certain medical conditions.
How does the body absorb vitamin B12 from the food we eat?
The process of absorbing vitamin B12 involves multiple steps:
Vitamin B12 is bound to proteins in food. Stomach acid and the enzyme pepsin help release it during digestion.
Once free, B12 binds to an intrinsic factor, a protein produced by the stomach lining. This complex protects B12 as it moves through the digestive tract.
The B12-IF complex is absorbed in the ileum, the last part of the small intestine.
Any disruption in these steps can impair absorption.
Stomach acid is important in the release of B12 from food. Hypochlorhydria or low stomach acid is one of the common reasons for poor absorption, mainly among older adults and those taking anti-acid medications. Intake of apple cider vinegar diluted with water before meals will stimulate the production of stomach acid that aids in vitamin B12 absorption.
Eat digestive bitters to help promote the production of digestive enzymes and stomach acid. Long-term use of proton pump inhibitors (PPIs) or H2 blockers can reduce stomach acid levels and impair B12 absorption, so avoid overuse of antacids.
Pair vitamin B12 rich foods with important nutrients like calcium (like dairy, fortified plant-based milk, and leafy greens), vitamin B9 (like leafy greens, legumes, and fortified cereals), and vitamin B6 (like bananas, poultry, and potatoes).
Healthy gut function is vital for B12 absorption. Probiotics improve gut health and may enhance nutrient absorption. Include fermented foods like yogurt and kimchi in your food. Prebiotics like garlic, onions, bananas, and whole grains feed good bacteria.
Conditions such as Crohn’s disease, celiac disease, and small intestinal bacterial overgrowth (SIBO) can affect the absorption. Medical advice is to be taken for appropriate treatment.
Heavy alcohol consumption damages the lining of the stomach and impairs B12 absorption. Alcohol should be taken in moderate amounts. Smoking can also interfere with nutrient absorption and increase the risk of B12 deficiency.
Some people carry genetic variants (for example, the MTHFR mutation), which alter the metabolism of B12. For them, methylated forms of B12, such as methylcobalamin, that bypass some metabolic steps would be helpful.
Signs your body is absorbing vitamin B12 better
When your body absorbs B12 efficiently, you may notice improvements in:
- Energy levels
- Cognitive function
- Mood stability
- Reduced numbness or tingling in extremities
- Healthier skin, hair, and nails
