Vitamin B12 is an important B vitamin. It is essential for healthy nerve tissue, brain function and the production of red blood cells. Cobalamin is another name for vitamin B12. A deficiency or insufficiency can occur when vitamin B12 levels become too low to meet the body’s needs. This situation can lead to a number of symptoms and can even progress to irreversible neurological problems if left untreated. About 6% of adults aged 60 or younger have vitamin B12 deficiency. This rate rises to 20% in people over 60.
Vitamin B12 is a water-soluble vitamin, like all other B vitamins. This means that it can dissolve in water and circulate in the blood. The body can store vitamin B12 for up to 4 years, and it can get rid of any excess vitamin B12 in the urine. Vitamin B12 is the largest and most structurally complex vitamin. It occurs naturally in animal products like meat and eggs, and manufacturers can produce it through bacterial fermentation synthesis.
Health Benefits of Vitamin B12
Vitamin B12 is crucial for various bodily processes, including:
– the normal functioning of the brain and nervous system
– cognitive functioning (ability to think)
– the formation of red blood cells and the prevention of anemia
– aid in the creation and regulation of DNA
– the possible prevention of congenital anomalies
– helps protect the eyes from macular degeneration
– necessary for the production of energy
Vitamin B12 is essential for healthy blood. When the body does not have enough B12, it leads to a decrease in the normal production of red blood cells (anemia), which affects the supply of oxygen. Megaloblastic anemia, also called nutritional deficiency anemia, is a type of anemia caused by B12 or folate deficiency. Megaloblastic anemia is characterized by impaired DNA synthesis and the formation of large, abnormal, immature red blood cells.
For adolescents and adults over the age of 14 the daily requirement is 2.4 micrograms (mcg) of vitamin B12. Pregnant people should consume 2.6 mcg, and breastfeeding people 2.8 mcg. Excess intake of vitamin B12 has not shown toxic or harmful qualities.
Certain medications can decrease the absorption of vitamin B12 from food. These drugs include:
– proton pump inhibitors
– H2 receptor agonists, often used in the event of peptic ulcer disease.
Foods containing vitamin B12
Vitamin B12 is naturally present in many animal products. It is generally not present in plant foods, unless it is supplemented.
Good dietary sources of vitamin B12 include:
– fish, especially haddock and tuna
– dairy products, such as milk, cheese and yogurt
– certain nutritional yeast products
Although vitamin B12 is found in many foods, some people are at increased risk of developing B12 deficiency or insufficiency. Groups at increased risk are:
– old people
– people on restrictive diets, such as vegan diets
– people with certain health problems, such as celiac disease.
Vitamin B12 Deficiency Symptoms
Low or insufficient B12 levels can lead to a number of symptoms, some of which can be serious. This can result in irreversible and potentially serious damage, particularly to the nervous system and the brain. However, this situation is infrequent. However, even slightly lower than normal vitamin B12 levels can trigger symptoms. However, these symptoms are not specific and are not sufficient to diagnose vitamin B12 deficiency. Symptoms may include:
– memory problems
– mood swings
– difficulty concentrating
When symptoms worsen, they may include neurological changes, such as numbness and tingling in the hands and feet. Some people may have difficulty keeping their balance.
Infants who lack vitamin B12 may have:
– unusual movements, such as facial tremors
– reflex problems
– feeding difficulties
– possible growth problems if not treated
B12 deficiency has been linked to an increased risk of cognitive impairment and depression.
Vitamin B12 deficiency can also lead to anemia. The most common symptoms of anemia are fatigue, shortness of breath and an irregular heartbeat. People with anemia may also experience the following symptoms:
– a sore mouth or tongue
– weight loss
– pale or yellowish skin
– problems with menstruation
Who is at risk for vitamin B12 deficiency?
Several groups of people may be at increased risk of vitamin B12 deficiency:
– Vegans are at risk of vitamin B12 deficiency because their diet excludes food products of animal origin. Pregnancy and lactation can aggravate the deficiency in vegans. Unless a vegan diet is carefully planned, it is difficult to get enough vitamin B12 through plant foods alone. This is why it is recommended that people on a vegan diet supplement with B12.
– People with pernicious anemia may lack vitamin B12. Pernicious anemia is an autoimmune disease that affects the blood. Patients with this disease do not have enough intrinsic factor, a protein found in the stomach that allows the body to absorb vitamin B12.
– Other risk groups include people with small intestine problems, for example someone whose small intestine has been shortened by surgery. Crohn’s disease is also a risk factor for vitamin B12 deficiency due to frequent involvement of the terminal ileum.
– Gastritis, celiac disease and inflammatory bowel disease (IBD) can lead to deficiency because these conditions reduce nutrient absorption.
– People with chronic alcohol-related disorders may lack vitamin B12 because their bodies do not absorb nutrients efficiently.
– People with diabetes treated with metformin should have their B12 levels tested regularly by their healthcare professional. Indeed, metformin reduces the absorption of vitamin B12.
– Treatment for vitamin B12 deficiency includes oral vitamin B12 supplements or vitamin B12 injections.
Some people have difficulty absorbing vitamin B12 from food and may need to take supplements.
Certain populations may have difficulty absorbing vitamin B12 from food, including:
– old people
– people with pernicious anemia
– people with intestinal disorders
People can take B12 supplements by mouth or as a nasal spray. However, oral supplements may not help in many cases of deficiency. In these circumstances, a doctor may recommend vitamin B12 injections.
Vegans and others who don’t get enough B12 from their diet can take supplements to avoid any deficiency. This is especially important during pregnancy and lactation.
Vitamin B12 injections by a doctor
Doctors may prescribe vitamin B12 injections for some people with pernicious anemia, or problems with vitamin B12 malabsorption and severe deficiency. These injections consist of vitamin B12 in the form of cyanocobalamin or hydroxocobalamin. A doctor usually gives these injections into a muscle every other day for two weeks, or until the person’s symptoms improve. Further treatment depends on the cause of the deficiency, whether it is diet-related or whether the person has neurological problems.
Hydroxocobalamin injections can cause side effects, including:
– pain, swelling or itching at the injection site
– nausea or vomiting
– hot flashes
Serious side effects are rare. However, if a person experiences palpitations or signs of allergic shock after an injection, they should contact their doctor immediately.
Vitamin B12 is an essential vitamin found primarily in animal products. Most adults need 2.4 mcg per day. The body needs vitamin B12 for the normal functioning of the brain and nervous system, the formation of red blood cells and other essential processes. Vitamin B12 deficiencies can lead to symptoms such as headaches, fatigue and digestive problems, even nerve damage and cognitive impairment. Some people are more prone to deficiencies, such as the elderly and those who don’t absorb nutrients well. Vegans may also be at risk for deficiency, as their diet excludes many sources of B12. Most people who eat a balanced diet get enough B12. For others, doctors may recommend oral supplements or injections.
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