B vitamins have a wide range of activities in the human body and are involved in almost every metabolic event. As a result, B vitamins are required for a variety of physiological functions, including neurotransmitter synthesis, energy production, cellular respiration, and DNA maintenance.

Longitudinal research studies have also found that a lack of particular B vitamins can hasten brain tissue degradation and impair cognitive performance, highlighting the importance of these vitamins for brain health.

You probably already knew those facts, but did you realize that small quantities of niacin can help prevent or reverse dementia? Or that thiamine shortage increases your chances of developing type 2 diabetes?

Let’s look at how B vitamins work, their research-backed advantages, the best ways to take them, and any potential side effects or safety concerns you should be aware of.

B Vitamins: Classification

B vitamins are a type of micronutrient, which means they’re compounds that your body needs in little amounts to survive. The recommended daily amount (RDA) of vitamin B12 for people, for example, is only 2.4 micrograms.

Macronutrients, on the other hand, are substances that your body needs in huge amounts in order to function properly (i.e. carbohydrates, proteins, fats, water). For example, the RDA for fat in a 2000-calorie diet for an adult is around 60 grams, which is 25 million times the RDA for vitamin B12. This demonstrates how complex and fragile the physiology of your body is.

A typical over-the-counter B vitamin “complex” supplement will generally contain the following ingredients:

  • Vitamin B1 (Thiamine)
  • Vitamin B3 (Niacin)
  • Vitamin B5 (Pantothenic acid)
  • Vitamin B6 (Pyridoxine)
  • Vitamin B9 (Folic acid)
  • Vitamin B12 (Cobalamin)

Other B vitamins, such as vitamin B2 (riboflavin) and vitamin B7 (biotin), are essential for life. The former is particularly critical for energy production, while the latter is essential for hair and skin health.

If you’re wondering why certain numbers, such as vitamin B4 (choline), B8 (inositol), and B10 (para-aminobenzoic acid/PABA), aren’t included in the list of B vitamins, it’s because they’re no longer regarded as vitamins and are instead classified as “pseudo vitamins” or “vitamin-like” macronutrients.

The Functions of the Primary B Vitamins

B vitamins are involved in a variety of processes, including cholesterol regulation, cellular respiration, neurotransmission, DNA repair, and the formation of blood cells. We’ll go through each key B vitamin separately in the subsections below due to its tremendous intricacy and distinct functions.

Vitamin B1 (Thiamine)

Thiamine is primarily responsible for turning glucose (sugar) and amino acids into useful energy, as well as the formation of red blood cells, as a coenzyme. Despite the fact that thiamine deficiency is uncommon, those who drink a lot of alcohol are at a higher risk, especially if their intestinal linings have been damaged.

When thiamine deficiency is present, the risk of type-2 diabetes is significantly increased due to unstable blood sugar balance. Furthermore, thiamine is required for the production of acetylcholine, an excitatory neurotransmitter that aids with focus, cognition, and motivation.

Vitamin B3 (Niacin)

Niacin is required for oxidation-reduction reactions, which are the foundation of cellular respiration (the mechanism by which cells convert metabolic energy from foods into ATP) (adenosine triphosphate). This vitamin is also in charge of controlling blood lipid levels by preventing the breakdown of fatty acids in the body, resulting in a decrease in cholesterol synthesis (particularly low-density lipoproteins, aka “bad” cholesterol).

Niacin also increases the production of a peptide called brain-derived neurotrophic factor in humans (BDNF). This peptide stimulates the formation and replication of neurons throughout the brain, two important processes that reflect cognitive performance.

Pellagra is a condition caused by niacin deficiency, which is known to occur only in impoverished people. This sickness is linked to serious mental illnesses like dementia. Moderate amounts of niacin, on the other hand, may be able to reverse the illness.

Vitamin B5 (Pantothenic acid)

The formation of coenzyme A, which subsequently becomes acetyl-CoA – a chemical essential for metabolism and energy production – is perhaps pantothenic acid’s most important role in the human body. Your body must first convert pantothenic acid to pantetheine (the active form of vitamin B5) before it can be used. There are no known illnesses connected to a pantothenic acid deficiency at this time, however, evidence suggests that supplementing with vitamin B5 can lower LDL (or “bad”) cholesterol levels.

Vitamin B6 (Pyridoxine)

Pyridoxine, like thiamine, is required for the metabolism of macronutrients and is also used in the synthesis of red blood cells. Additionally, pyridoxal phosphate, the active form of vitamin B6, is required for upwards of 160 recognized essential processes in the body.

Furthermore, pyridoxal phosphate is necessary for the conversion of levodopa to dopamine, as well as the conversion of glutamate to GABA and appropriate L-tryptophan metabolism (which is a precursor to serotonin). As a result, vitamin B6 deficiency can cause a variety of cognitive problems.

Pyridoxine deficiency is most common in chronic alcoholics and can lead to depression, anemia, high blood pressure, insomnia, neuropathy, and a range of other health problems.

Naturally, if you wish to avoid B vitamin shortages, you should limit your alcohol usage.

Vitamin B9 (Folic acid)

Folic acid, which works in tandem with vitamin B12 to produce and fix DNA, as well as hemoglobin, a protein found in red blood cells that transports oxygen to tissues, is essential for practically every physical reaction in the body that includes a one-carbon transfer.

Folic acid deficiency is uncommon because it is produced by your intestinal bacteria; however, malnourished persons may become anemic as a result of a lack of this vitamin. Furthermore, too much folic acid in the body might prevent zinc absorption and produce convulsions, hence excessive folic acid consumption is prohibited.

Vitamin B12 (Cobalamin)

Cobalamin is the most complicated vitamin biochemically. Cobalamin is a complex vitamin that plays an important role in the brain and central nervous system (which are fittingly the most complex parts of your body). Cobalamin, like folic acid, is involved in the production of DNA and the metabolism of all amino acids generated in the body.

Because it’s involved in methyl group-transfer activities, methylcobalamin is one of the most frequent forms of this vitamin in your body (which are rather numerous as part of your metabolism). Furthermore, cobalamin metabolism is extremely complicated, making it one of the most prevalent B vitamin deficits in humans.

Cobalamin deficiency can cause major, irreversible health problems, such as brain and nerve system structural damage or even pernicious anemia (lack of red blood cell manufacturing). This is why most doctors recommend cobalamin shots to their patients.

Furthermore, cobalamin is required for the conversion of homocysteine to methionine; methionine is an amino acid that the body needs to make S-adenosyl-methionine (SAMe), which is subsequently used to make numerous catecholamines and other vital biomolecules. As a result, cobalamin is essential for controlling mood and cognition (through SAMe), as a deficit can lead to despair and anxiety.