Vitamin B12 Benefits: Symptoms of Deficiency

Vitamin B12 is an important B vitamin. It is essential for healthy nerve tissue, brain function, and red blood cell production. Cobalamin is another name for vitamin B12. A deficiency or deficiency can occur when levels of vitamin B12 become too low to meet the body’s needs. This situation can lead to a number of symptoms and can develop into irreversible neurological problems if left untreated. About 6% of adults age 60 or younger have a vitamin B12 deficiency. This rate rises to 20% in people over the age of 60.

Vitamin B12 is a water-soluble vitamin like all other B vitamins, meaning that it can dissolve in water and circulate in the blood. The body can store vitamin B12 for up to 4 years, and can eliminate 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.

Health Benefits of Vitamin B12

Vitamin B12 is important for various body processes, including:

The normal functioning of the brain and nervous system
Cognitive performance (the ability to think)
Formation of red blood cells and prevention of anemia
Aiding in the formation and regulation of DNA
Possible prevention of congenital malformations
Helps protect eyes from macular degeneration
Necessary for energy production
Vitamin B12 is essential for healthy blood. When the body does not have enough vitamin B12, it leads to a decrease in the normal production of red blood cells (anemia), which affects the oxygen supply. Megaloblastic anemia, also known as nutritional deficiency anemia, is a type of anemia caused by a deficiency of vitamin B12 or folic acid. Megaloblastic anemia is characterized by impaired DNA synthesis and the formation of large, abnormal, immature red blood cells.

Entry requirements

For adolescents and adults over 14 years of age, the daily requirement is 2.4 micrograms (mcg) of vitamin B12. Pregnant women should consume 2.6 micrograms and breast-feeding 2.8 micrograms. Excessive intake of vitamin B12 has not been shown to be toxic or harmful.

Some medications can reduce the absorption of vitamin B12 from food. These medications include:

– metformin
Proton pump inhibitors
H2 receptor agonists, often used in peptic ulcer disease.

Foods that contain Vitamin B12

Vitamin B12 is found naturally in many animal products. It is not generally found in plant foods, unless it is supplemented.

Good food sources of vitamin B12 include:

– beef
– pork meat
– pork meat
– Poultry
– sheep meat
Fish, especially haddock and tuna
Dairy products such as milk, cheese and yogurt
Some nutritional yeast products
– eggs

Although vitamin B12 is found in many foods, some people are at increased risk of developing a vitamin B12 deficiency or deficiency. Groups at increased risk are:

– the elderly
People who follow restrictive diets, such as vegetarian or vegan diets
People with certain health problems, such as celiac disease.

Symptoms of Vitamin B12 deficiency

Low or insufficient B12 levels can lead to a number of symptoms, some of which can be serious. This can lead to serious and irreversible damage, especially to the nervous system and brain. However, this situation is rare. However, a somewhat low level of vitamin B12 can cause symptoms. However, these symptoms are not specific and are not sufficient to diagnose a vitamin B12 deficiency. Symptoms may include:

– depression
– confusion
Memory problems
– Tired
– Headache
– 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 find it difficult to maintain their balance.

Children who lack vitamin B12 may have:

Unusual movements such as facial jerk
Reflection problems
Feeding difficulties
– irritation
Possible growth problems if left untreated
Vitamin 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 have the following symptoms:

– Inflammation of the mouth or tongue
– Weight loss
Pale or yellowish skin
– Diarrhea
Menstrual problems

Who is at risk of vitamin B12 deficiency?

Several groups of people may be at higher risk of developing a vitamin B12 deficiency:

Vegetarians are at risk of vitamin B12 deficiency because their diet excludes food products of animal origin. Pregnancy and breast-feeding can exacerbate the deficiency in vegetarians. Unless a vegetarian diet is carefully planned, it is difficult to get enough vitamin B12 through plant foods alone. For this reason, vitamin B12 is recommended for people who follow a vegan diet.

-People with pernicious anemia may suffer from vitamin B12 deficiency. Pernicious anemia is an autoimmune disease that affects the blood. Patients with this disease do not have enough intrinsic factor, which is a protein in the stomach that allows the body to absorb vitamin B12.

Other risk groups include people with small intestine problems, for example people whose small intestine has been shortened by surgery. Crohn’s disease is also a risk factor for vitamin B12 deficiency due to the 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 who are treated with metformin should have their B12 levels checked regularly by a healthcare professional. In fact, metformin reduces the absorption of vitamin B12.

Treatment for vitamin B12 deficiency includes oral vitamin B12 supplementation or vitamin B12 injections.


Some people have difficulty absorbing vitamin B12 from food and may need to take a supplement.

Certain populations may have difficulty absorbing vitamin B12 from food, including:

– the elderly
People with pernicious anemia
– People with intestinal disorders
People can take B12 supplements orally or as a nasal spray. However, oral supplementation may not help in many cases of deficiency. In these circumstances, a doctor may recommend vitamin B12 injections.

Vegetarians and others who do not get enough vitamin 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 will usually give these injections into a muscle every two days for two weeks, or until a person’s symptoms improve. Further treatment depends on the cause of the deficiency, whether it is related to diet 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
– Headache
– vertigo
Hot flashes
Serious side effects are rare. However, if a person experiences palpitations or signs of anaphylactic shock after the injection, they should contact their doctor immediately.

Vitamin B12 is an essential vitamin found primarily in animal products. Most adults need 2.4 micrograms 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 deficiency can lead to symptoms such as headaches, fatigue, digestive problems, and even nerve damage and cognitive impairment. Some people are more prone to deficiency, such as the elderly and those who do not absorb nutrients well. Vegetarians may also be at risk of deficiency, because their diet excludes many sources of vitamin B12. Most people who eat a balanced diet get enough vitamin B12. For others, doctors may recommend supplements or oral injections.


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* Presse Santé strives to convey health knowledge in a language accessible to all. In any case, the information provided cannot replace the advice of a health professional.

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