(Nervous System) Vitamin B12 Deficiency: Its Neurological Consequences and Neuropathy
B-complex vitamins are important for various functions in the human body. Whether it is energy production, body defense mechanisms, or red blood cell formation, the B-group vitamins play pivotal roles by working in tandem or individually. Vitamin B12, in particular, has a great impact on neurological health.
When it comes to neurological concerns, vitamin B1 (thiamine), B2 (riboflavin), B3 (niacin), B7 (biotin), B6 (pyridoxine), B9 (folate, synthetically known as folic acid), and B12 (cobalamin) are especially important. These B-group vitamins have specific effects on brain cell functions and their deficiency leads to different neurological and psychological problems. Vitamin B12 deficiency is not very common in young adults but older people are more prone to this condition.
Vitamin B12, or cobalamin, is an essential vitamin for the proper functioning and development of the brain and nerve cells. It plays an important role in the maintenance of the sheaths that cover and protect the nerves of the central and the peripheral nervous system, ensuring fast and effective nerve-impulse transmission.
A fatty substance called myelin is essential for the formation of these sheaths. Vitamin B12 plays a significant role in the synthesis and maintenance of myelin. The neurological problems caused by vitamin B12 deficiency later in life are due to the damage caused to the myelin sheath.
Vitamin B12 Deficiency Neuropathy
Vitamin B12 is an essential dietary nutrient — a B12 deficiency can lead to a number of serious conditions including peripheral neuropathy.
Peripheral neuropathy may occur as a result of malnutrition, for which there are many causes including poor nutrition caused by an unbalanced diet and/or alcoholism. Additionally, a clear link has been established between a lack of vitamin B12 and peripheral neuropathy.
Symptoms of lack of vitamin B12 can cause serious anemia, nerve damage and degeneration of the spinal cord. It is common for anemia to develop first, but this is not always the case, especially if a person is taking a folate supplement. A lack of B12 damages the myelin sheath that surrounds and protect nerves. Without this protection, nerves cease to function properly and conditions such as peripheral neuropathy occur. Even B12 deficiency that is relatively mild may affect the nervous system and the proper functioning of the brain. The nerve damage caused by a lack of B12 may become permanently debilitating, if the underlying condition is not treated.
Symptoms and Signs
- Fatigue — The most classic b12 deficiency symptom. Fatigue is a subjective feeling of tiredness that has a gradual onset. Unlike weakness, fatigue can be alleviated by periods of rest. Fatigue can have physical or mental causes.
2. lethargy — Lethargy is a symptom that causes you to feel sleepy or fatigued and sluggish. This sluggishness may be physical or mental. People with these symptoms are described as lethargic. Lethargy can be related to an underlying physical or mental condition.
3. Poor Memory — It is caused by depression. Depression has been linked to memory problems, such as forgetfulness or confusion. It can also make it difficult to focus on work or other tasks, make decisions, or think clearly. Stress and anxiety can also lead to poor memory.
4. Depression — Depression (major depressive disorder) is a common and serious medical illness that negatively affects how you feel, the way you think and how you act. Fortunately, it is also treatable. Depression causes feelings of sadness and/or a loss of interest in activities once enjoyed.
5. Constipation — Constipation is a condition of the digestive system where an individual has hard feces that are difficult to expel. In most cases, this occurs because the colon has absorbed too much water from the food that is in the colon.
6. Headaches — headache is a very common condition that causes pain and discomfort in the head, scalp, or neck. It’s estimated that 7 in 10 people have at least one headache each year.
7. Loss of Appetite — A decreased appetite occurs when you have a reduced desire to eat. It may also be known as a poor appetite or loss of appetite. The medical term for this is anorexia.
8. Weight Loss — Weight loss, in the context of medicine, health, or physical fitness, refers to a reduction of the total body mass, due to a mean loss of fluid, body fat or adipose tissue or lean mass, namely bone mineral deposits, muscle, tendon, and other connective tissue. Weight loss can either occur unintentionally due to undernourishment or an underlying disease or arise from a conscious effort to improve an actual or perceived overweight or obese state.
Evaluation & Tests For B12 Deficiency
There are diagnostic tests to screen for vitamin B12 deficiency, to uncover the cause of B12 deficiency and to monitor the effectiveness of treatment.
Test to assess nerve damage include:
- Neurological exam
- Electromyography
- Nerve conduction velocity test
- Blood test
Treatment & Therapy
(Not all treatments and therapies may be indicated.)
- Increase B12 in diet with:
-Red meat
-Poultry and eggs
-Dairy products
-Fish
-Vitamin B12 supplements - Oral therapy of B12
- Injections of B12 are usually necessary
- Take safety measures to compensate for loss of sensation
- Early diagnosis and treatment may restore nerve damage
Neurological Consequences
- Vitamin B12 assists an important step of the One-carbon cycle
The proper functioning of the central nervous system is dependent on One-carbon metabolism that takes place in the brain. The One-carbon cycle actually includes a series of biochemical reactions that occur in every cell of the human body. The cycle is crucial for the synthesis of DNA, RNA, neurotransmitters, membrane phospholipids, and myelin. Among these, the neurotransmitters (serotonin, dopamine, acetylcholine, and nor-epinephrine) are essential for the maintenance of the cognitive functions of the brain, and myelin is required for neuronal protection and communication as described above.
2. Vitamin B12 acts as a coenzyme in another important reaction that is needed for myelin synthesis and stabilization
Another biochemical reaction, the conversion of methylmelonyl-CoA into succinyl CoA, also requires the coenzyme cobalamin. If this reaction does not occur, methylmalonyl-CoA gets converted to methylmalonic acid (MMA), which is a myelin destabilizer. Excess MMA leads to the synthesis of abnormal fatty acids instead of myelin. These abnormal fatty acids are incorporated into neuronal lipids leading to the formation of a fragile myelin sheath. Subsequently, abnormal myelination or demyelination occurs. The result is severe central and peripheral nervous system dysfunction.
3. Vitamin B12 deficiency causes various neuropsychiatric problems ranging from neuropathy to dementia in the elderly
Vitamin B12 deficiency is found to cause neurological and psychiatric problems in adults between 40–90 years of age. It rarely affects people younger than this. The neurological manifestations include myelopathy (disease of the spinal cord), neuropathy (disease of the nerves), sensory disturbances, gait abnormalities, and weakness, while the psychiatric problems range from cognitive and behavioral disturbances to dementia.
4. Vitamin B12 and folate deficiencies in fetal and early life cause poor brain development and cognitive functions
Folate and vitamin B12 play very important roles in brain development, especially during the fetal and first 2 years of life. Furthermore, these vitamins are essential till puberty as myelination that starts during fetal life continues untill puberty. As mentioned above, vitamin B12 deficiency results in restricted myelination, and depending on the area of the nervous system affected, the child can present with varied cognitive and intellectual problems. Pregnant women with folate and B12 deficiency need supplements to prevent the development of these neurological complications.
Vitamin B12 thus proves to be a very important micronutrient for brain health in both the children and the elderly. There are various conditions that may lead to the deficiency of this vitamin. But if the cause is due to a dietary deficiency, the proper and timely supplementation of this ‘nervous vitamin’ can prevent damage to the nervous system. The vitamin is abundant in animal foods and healthy vegan diets are fortified with this vitamin.
So, Now you should be taking more vitamin b12 so that you can prevent vitamin b12 deficiency which can cause neurological diseases and neuropathy such as Anemia and Anorexia. Vitamin B12 is a nutrient that helps keep the body’s nerve and blood cells healthy and helps make DNA, the genetic material in all cells. Always take vitamin B12 in a right dosage everyday and keep your body healthy.
Vitamin B12 Deficiency
References:
https://www.foundationforpn.org/what-is-peripheral-neuropathy/causes/vitamin-nutrition-deficiency/
http://brainblogger.com/2014/07/30/vitamin-b12-deficiency-and-its-neurological-consequences/
https://www.healthline.com/symptom/lethargy
https://www.medicalnewstoday.com
https://www.healthline.com/health/depression/depression-and-memory-loss
https://www.psychiatry.org/patients-families/depression/what-is-depression
https://www.medicalnewstoday.com/articles/150322.php
https://www.healthline.com/health/headache
https://www.healthline.com/symptom/anorexia