Content :
Vitamin B12, or cobalamin, is a water-soluble vitamin very important for the normal functioning of the brain, nervous system and blood formation. In this article, we explain the causes of vitamin B12 deficiency, its symptoms, diagnosis and possible treatments.
◉ Definition
Vitamin B12, also known as cobalamin, is a vitamin that plays an essential role in the maintaining the health of our nervous system, the formation of red blood cells and the production of energy.
This vitamin is naturally present in different foods, in food supplements or in the form of medical treatments.
If someone lacks vitamin B12, it may be that at the beginning of this deficiency, no significant manifestations are felt. However, over time, it can lead to health issues such as neurological symptoms, anemia, and fatigue.
A health professional can detect this deficiency by ordering a blood test to analyze vitamin B12 levels.
◉ Function and Importance of Vitamin B12
Vitamin B12 plays a critical role in several essential bodily functions, including
- Nervous System: It's crucial for the nervous system, aiding the production of myelin which safeguards nerve fibers, facilitating nerve signal transmission.
- Red Blood Cells Production: In bone marrow, it collaborates with other B vitamins, like folic acid, for red blood cell synthesis and maturation.
- DNA Synthesis: It's necessary for DNA synthesis, vital for cell division and proper tissue growth throughout the body.
- Energy production: Vitamin B12 converts carbohydrates into energy (glucose) and helps break down fatty acids and amino acids into energy.
- Brain Health: Adequate levels of vitamin B12 are important for maintaining cognitive function as one ages.
- Anti-allergic role: Vitamin B12 may also reduce inflammation in the body by blocking the release of histamine.
◉ Food Sources of Vitamin B12
Vitamin B12 is present in numerous natural sources, primarily derived from animal products, while its presence in plant-based foods is limited or absent. As with most nutrients, some food industries have focused on fortifying their products with vitamin B12 to make it more widely available
◉ Natural sources of vitamin B12 include
- Beef liver
- Shellfish and most seafood
- Cheese and dairy products
- Red and white meats
- Eggs
- Nutritional yeast
- Soy milk
- Dried seaweed
- Fortified foods.
◉ Causes of Vitamin B12 Deficiency
Speaking about vitamin B12 deficiency, it should be noted that it is relatively uncommon due to the availability of this vitamin in many commonly-consumed foods. A deficiency occurs when the body does not consume enough or fails to absorb enough.
◉ Generally, the causes of vitamin B12 deficiency include
- Inadequate Dietary Intake of Vitamin B12 (vegetarian or vegan diet).
- Gastritis, characterized by reduced production of hydrochloric acid and decreased efficiency of absorption, may increase the risk of deficiency.
- Pernicious anemia is a rare condition where the absence of special protein, called intrinsic factor (IF), hampers vitamin B12 absorption in the intestines.
- Digestive diseases such as Crohn's disease,celiac disease, bacterial, and parasitic infections.
- An addiction to alcohol beverages that inhibits the absorption of the required amount of this vitamin.
- Immune diseases such as systemic lupus erythematosus and Graves' disease.
- Surgical procedures, such as a gastric bypass, that modify or remove portions of the stomach or small intestine.
- Taking medications that interact with this vitamin and inhibit its absorption.
- In many older adults, insufficient stomach hydrochloric acid hinders the absorption of vitamin B12.
◉ Symptoms of Vitamin B12 Deficiency
If you're experiencing early-stage vitamin B12 deficiency, you're unlikely to notice any clear symptoms other than mild fatigue and physical weakness. However, if this mild deficiency isn't treated, it can progress to a severe deficiency with the following symptoms:
- Megaloblastic anemia (a form of macrocytic anemia).
- Chronic physical weakness and fatigue.
- Sudden dizziness.
- Accelerated heartbeat.
- Shortness of breath.
- Skin paleness.
- Tongue redness, irritation, and sores.
- Intermittent digestive disturbances between constipation and diarrhea.
- Loss of appetite.
- Numbness in the extremities.
- Tingling sensation in the hands and feet.
- Muscular weakness.
- Blurred vision.
- Memory problems.
- Non-reversible nerve damage.
◉ Treatment
Vitamin B12 deficiency is primarily treated through dietary supplements containing carefully measured amounts of the vitamin. However, in cases of severe deficiency or when the body is unable to absorb the vitamin from the digestive system, treatment is administered through high-concentration vitamin B12 injections to compensate for the deficiency.
◉ Recommended intake of vitamin B12
- Daily dose for children aged 1 to 12 years: 0.5 to 1.5 micrograms per day.
- Daily dose for adolescents aged 13 to 18 years: 2 to 2.3 micrograms per day.
- Daily dose for adults over the age of 18 years: 2.4 micrograms per day.
- Daily dose for pregnant women: 2.6 micrograms per day.
- Daily dose for breastfeeding women: 2.8 micrograms per day.
◉ Prevention
There are a set of guidelines and tips related to preventing vitamin B12 deficiency targeting individuals who have recovered from B12 deficiency or patients who suffer from one of the risk factors for the deficiency, such as those planning to lose a significant amount of weight, recent gastric bypass surgery patients, or even elderly individuals with digestive problems. Here are some of the most important recommendations:
- If you follow a vegetarian diet, be sure to incorporate vitamin B12 supplements daily to meet specific needs.
- Include foods fortified with vitamin B12, such as breakfast cereals, into your weekly shopping list.
- Avoid the consumption of alcoholic beverages which negatively impact vitamin B12 levels and cause organ damage.
- Be selective in your use of medications and do not underestimate the possible side effects of widely available treatments that may not be suitable for your condition.
- Perform laboratory tests on a regular basis and do not neglect their results, as they can detect various serious conditions that can be treated at an early stage.
◉ Frequently asked questions
What are the medications that interact with vitamin B12 and hinder its absorption?
Since the absorption of this vitamin occurs in the digestive system, some patients complain of B12 deficiency despite taking dietary supplements. Sometimes, the cause may be attributed to taking certain chronic medications that affect the drug's absorption, including:
- Proton pump inhibitors such as omeprazole, esomeprazole, and lansoprazole.
- Histamine-2 receptor antagonists such as famotidine.
- Some blood sugar-lowering medications such as metformin
- Gout treatments like colchicine.
Does vitamin B12 deficiency affect the fetus of a pregnant woman?
Having a good level of vitamin B12 ensures that the fetus receives adequate blood supply and protects it from genetic mutations. On the other hand, severe deficiency of this vitamin can affect the child's growth in the future, increasing the probability of delayed physical and mental development.
Do high doses of vitamin B12 cause toxic effects?
Because vitamin B12 is a water-soluble vitamin, excess amounts are excreted in the urine. The maximum amount of this vitamin is 1000 micrograms, which is a very large amount compared to the recommended daily doses. Nevertheless, we recommend not taking this vitamin randomly, but consulting a physician first.
What are the types of anemia caused by a vitamin B12 deficiency?
Vitamin B12 deficiency can cause two types of anemia with mostly similar symptoms:
- Megaloblastic Anemia: This is the most common type associated with vitamin B12 deficiency.
- Pernicious anemia: a specific form of megaloblastic anemia due to a lack of intrinsic factor, a protein necessary for the absorption of B12.
