The human body benefits from essential amines in a variety of ways. Although they have a low demand in the body compared to other nutrients, the functions they fulfill are more than any other nutrients. One such vitamin is cobalamin (also known as vitamin B12), required for the body’s constructive functions. Vitamin B12 deficiency results in a variety of CBS-related disorders. In this article, we intend to highlight the effect of B12 deficiency on the brain. However, before we read more about the impact of Vitamin D deficiency on the human brain, let us know some basic facts.

Basic facts about Vitamin B12:
Vitamin B12, scientifically termed cobalamin, is a necessary component that can only be derived through animal sources. For example, meat, fish, milk, cheese, and eggs are the only natural sources of B12 in the diet and can also be consumed as a supplement or added to foods.

The absorption of vitamin B12 occurs in two stages:

  • Vitamin B12 is extracted from food in the first stage with the help of gastric acid in the stomach, and then it binds with the intrinsic factor (a protein secreted in the stomach).
  • Following that, vitamin B12 combined with intrinsic factors travels further down the gastrointestinal tract before being absorbed in the distal region of the ileum.

Vitamin B12 is a water-soluble vitamin essential for the proper functioning of your brain and nervous system. In addition, it is required for the synthesis of red blood cells and DNA.

The daily recommended and required amount of vitamin B-12 is approximately 2.4 micrograms for individuals. In case of a low intake of cobalamin, its deficiency ensures exhibiting various signs and symptoms. These commonly include anemia, fatigue, numbness, tingling sensations, etc.

Out of all the commonly noticed symptoms, the impact of Vitamin B12 deficiency on the brain has exhibited leaps in the world of research. As it performs critical biological functions, it’s essential to keep track of whether its levels in the body are optimally maintained. Vitamin B 12 deficiency can cause physiological processes to go haywire, resulting in various diseases. In addition, nutrients like Vitamin B12 have been extensively studied in recent years in brain development and functioning. Several studies have recorded the ill effects of Vitamin B12 deficiency in brain health.

Roles of Vitamin B12 in maintaining brain health:

It is a fact that the B group of vitamins is transported efficiently across the blood-brain barrier into the blood circulation, thereby implying their roles in neurological functions. Hence it is quite understandable that these vitamins can detail the brain about its physiological roles and duties.

Studies show that Vitamin B12 plays a crucial role in brain function at all ages. It also aids in the prevention of CNS developmental problems, mood disorders, and dementia in the elderly, such as Alzheimer’s disease and vascular dementia.

Vitamin B12 and folate pills boost serotonin and dopamine synthesis when given together. Both vitamins are vital for controlling and maintaining the mental status of an individual.

Neurological effects on the brain due to B12 deficiency

The symptoms of B12 deficiency show up gradually over time. The neurological symptoms commonly include

  • Fatigue
  • Light-headedness
  • Confusion
  • numbness and tingling sensations
  • difficulty in coordination
  • memory problems.

Paresthesias (numbness and tingling sensation in hands and feet) and loss of balance are the most prominent features of Vitamin B12 deficiency. This disorder is a demyelinating disease. It occurs due to simultaneous degeneration of the lateral and posterior funiculi of the spinal cord due to defective myelin sheaths. Patients first detect paraesthesia in their feet and sometimes their hands, extending throughout the limbs as the condition progresses. Following the sensory problems, the patient starts to experience motor impairments like muscle weakness, motor coordination disorders, and in the worst case, paralysis symptoms. If left untreated, the patient might undergo paraplegia.

There can also occur damage to the central tracts and the brain leading to specific psychiatric symptoms. These symptoms might include confusion, catatonia, apathy, stupor, memory and judgment disorders, or even psychoses, depressions, and dementia.

According to some studies, low vitamin B-12 levels have been linked to a higher risk of dementia. Memory loss or dementia is probably due to brain atrophy, which means decreased brain cells, i.e., neurons. Decrease in Vitamin B12 concentrations within the normal range or below are seen to be associated with poor memory performance, which is an effect that is partially mediated by the reduced microstructural integrity of the hippocampus. In addition, some scientific studies have found the combination of vitamin B12 and omega-3 fatty acid supplementation to be efficacious in persons with early-stage dementia.

Vitamin B12 deficiency can affect cognitive functions in children
Reports have suggested that the cognitive functions in newborns are affected by the Vitamin B12 status in the mother during pregnancy. The clinical signs of Vitamin B12 deficiency in babies and small children whose mothers had Vitamin B12 deficiency demand extra care. Such infants are more likely to have severe hematological and neurological abnormalities, long-term consequences for a child’s development. That’s the reason why mothers should be supplemented with Vitamin B12 to avoid any foreseen complications. According to some studies, vitamin B12 supplementation appears necessary to improve pregnancy outcomes and minimize neurodevelopmental problems.

Vitamin B12 deficiency and brain health in Elderly
Vitamin B 12 in the proper functioning of the brain is not limited only to infants and adults but is also necessary for the elderly population. It prevents mood disorders and dementia in the elderly. In addition, it plays a crucial role in mental disorders such as Alzheimer’s disease and vascular dementia. Treatment using Vitamin B12 supplements has been suggested in several studies for people suffering from disabling limitations such as memory loss in Alzheimer’s disease.

The symptoms of Vitamin B12 deficiency take time to manifest, thus making it treatable in its early stages. Therefore, early diagnosis and proper management of the disease can definitely help in preventing further complications.


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