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B Complex vs B12: Which One is Better for You?

It's well known that vitamin B12 is one of the vitamins that need to be supplemented on a plant-based or vegan diet, but is it better to choose vitamin B complex or vitamin B12? Read on and find out.
Jyothi Shenoy, MD, MBA

Written by Jyothi Shenoy, MD, MBA. Updated on November 21, 2022.

Vitamin B12 has gained immense popularity for the wide range of benefits it provides. It is highly regarded for its ability to work as an energizer, natural sleep aid, and stress reliever.

Vitamin B12 is, in fact, one of the B vitamins that together form the B complex.

The popularity of vitamin B12 seems to have somewhat masked the importance of other B vitamins that are equally essential for maintaining optimum health.

Hence, there is a need to be aware of the roles and functions of vitamin B12 as well as B complex so that the importance of these nutrients becomes clear.

Here is a detailed analysis of the functions of vitamin B12 and B complex and the unique needs of the body for these nutrients.

This information is aimed at enabling you to make the right decisions about your food choices based on the risks linked to their deficiencies.

What’s the Difference Between B12 and B Complex Vitamins?

Vitamin B12 is an essential nutrient that the body can not produce. It is present in several non-vegan food sources such as beef liver, eggs, meat, and poultry.

This is why; vegans often have to rely on B12-fortified cereals and plant-based drinks to ensure they are receiving an adequate amount of this nutrient.

Vitamin B12 is specifically noted for its ability to provide an energy boost to the body. It can increase the supply of energy to the cells thus improving cellular functions.

It can also be beneficial for preventing heart diseases, thanks to its ability to improve fat metabolism and regulate cholesterol levels in the body.

Moreover, it is needed for the synthesizing of DNA in the cells, which suggests the deficiency of this nutrient might lead to DNA mutations that could trigger cancerous changes in the healthy tissues.

While these benefits make vitamin B12 a valuable nutrient, it is important to note that it can not alone boost energy or improve your overall health and fitness.

This is where comes the role of other B vitamins that are equally important for maintaining the body’s normal functioning.

Most people, after experiencing the impressive health benefits of vitamin B12, tend to believe that they need to focus only on their intake of this nutrient while negating the need for other B vitamins.

However, it would be wrong to assume that vitamin B12 alone can take care of the physiological functions occurring in different organs.

The body needs several other nutrients including minerals as well as B vitamins to be able to sustain normal functioning and prevent disease development.

B vitamins that form the B complex are water-soluble vitamins. This means they can not be stored in the body and can get eliminated via urination.

Also, these vitamins must be dissolved in water before they can be absorbed and used up by cells. This emphasizes the need for regular intake of these nutrients.

However, although the B complex does not stick around for too long inside the body, it still supports a variety of functions within the duration they are available to the tissues.

B-complex comprises eight types of vitamins. These vitamins have the ability to enhance cellular metabolism, create energy, and improve brain functions, among many other benefits.

Vitamin B12, just as the name suggests, is a part of the B-complex family. The remaining B vitamins in this complex include the following:

  • Vitamin B1 (also called Thiamine)
  • Vitamin B3 (also called Niacin)
  • Vitamin B2 (also called Riboflavin)
  • Vitamin B5 (also called Pantothenic Acid)
  • Vitamin B7 (also called Biotin)
  • Vitamin B6 (also called Pyridoxine)
  • Vitamin B9 (also called Folic Acid)

Each of these nutrients has its own unique functions, which make B complex just as essential for the body as vitamin B12.

Should I Take B12 or B Complex?

It is clear that the only difference between B Complex and vitamin B12 is that vitamin B12 is just one of the 8 vitamins that form the B complex.

In most supplements, the set of eight B vitamins is presented in the optimum ratio or balance to provide the daily recommended amount for each.

There is a lot of curiosity about whether to take vitamin B12 or B complex.

It is common for people to believe that if they use supplements containing vitamin B12, they would be deprived of the health benefits of other B vitamins.

Some other people believe that they need not take B complex as vitamin B12 can take care of their health needs. They do not want to take excess supplementation and prefer to take only vitamin B12.

The confusion about whether to take vitamin B12 or B complex can be resolved by analyzing one’s specific needs.

Both these approaches can offer benefits to patients depending on the symptoms they are experiencing and the related nutritional deficiencies they might be suffering from.

Also, since all B vitamins are water-soluble, they cannot be stored in the body.

So, even if you happen to ‘overdose’ on the B vitamins or use an excess of vitamin B12 or B complex supplements, the body will simply excrete the excess amount that is left unabsorbed or unused.

Hence, it is acceptable to take Vitamin B12 or B complex supplements.

However, you must ensure that amount of nutrients you consume should be enough to meet the body’s requirements. Also, you need to consume these nutrients on a regular basis as the body can not store them.

The inadequate intake or irregular use of supplements would eventually equate to a low supply of these nutrients putting you at risk of conditions linked to their deficiencies.

What Are the Benefits of Vitamin B12?

Depression Treatment and Prevention

Vitamin B12 can help to restore a healthy balance of hormones in the nervous system thus improving mood. It can specifically help to boost the secretion of a feel-good hormone called serotonin thus reducing the risk of depression.

Increasing the intake of foods rich in vitamin B12 has also been linked to better chances of complete recovery from depressive disorders.

Prevents Macular Degeneration

The adequate intake of vitamin B12 is essential for protecting the tissues of the eyes such as the macula and retina against age-related degenerative changes.

It may lower the level of a compound called homocysteine in the blood, and thus, inhibit the development of an eye disease called macular degeneration that is known to cause blindness.

Pregnancy Health

An adequate supply of vitamin B12 is essential during pregnancy for ensuring the proper growth and development of the fetus.

Women having a deficiency of vitamin B12, especially in the early stages of pregnancy, have an increased risk of miscarriage and a low birth weight baby.

They may also experience developmental complications in the child such as neural tube birth defects.

Improves Cognitive Functions

Vitamin B12 can play a role in enhancing the cognitive functions of the brain such as memory, focus, and attention span.

The deficiency of this nutrient can affect these cognitive functions, affecting the performance of students and working professionals at school and the workplace, respectively.

Prevents Anemia

Vitamin B12 improves the functions of the nerve cells and helps in the formation of red blood cells.

A low intake of foods containing vitamin B12 can cause the red blood cells to be formed improperly thus elevating the risk of anemia, as well as a form of blood cancer known as acute myeloid leukemia.

It can also trigger other hematologic alterations such as pancytopenia, hypersegmentation of neutrophils, myelodysplastic syndrome, and macrocytosis.

Prevents Brain Atrophy

Vitamin B12 can help to support the activities of the nerve cells called neurons in the brain.

It can reduce the risk of brain atrophy, which occurs due to the loss of neurons, thereby preventing associated symptoms like memory loss or dementia.

What are the Benefits of B Complex?

Energy Generation

Vitamins B1, B3, and B6 can help in the conversion of glucose into energy. Vitamin B2 can help to increase energy levels, while also acting as a powerful antioxidant.

Immune Support

B complex provides strong support to the immune system and helps to improve the body’s defense mechanisms against infections. It may also reduce the risk of autoimmune disorders to some extent.

Cellular Communication

Vitamin B3 can help the cells communicate with each other and thus, regulate the functions of different organs that are dependent on cellular signaling or the body’s feedback mechanisms.

DNA Production

Vitamin B3 and B5 are needed for the synthesis of DNA in the cells. These nutrients can also prevent mutations in the DNA thus reducing the risk of cancer. Vitamin B7 can also control gene expression, and thus, protect healthy tissues against abnormal cancerous changes.

Improve Diabetes Control

Vitamin B6 can regulate blood sugar levels and reduce the risk of diabetes. It is believed to work by improving the utilization of glucose by the cells to meet their energy need.

It can also restore a healthy balance of hormones and regulate the secretion of insulin in the pancreas.

This is an important benefit of the B complex that can play a crucial role in the prevention of type 1 diabetes that occurs due to the insufficient secretion of insulin.

These benefits are supported by vitamin B7, which specifically helps in the metabolism of carbohydrates and fats and prevents a rise in blood sugar levels thereby protecting against the complications of diabetes.

Formation of Blood Cells

Vitamin B9 assists in the formation of blood cells and reduces the risk of anemia.

This can improve the transport of oxygen to all the tissues and organs of the body allowing them to function optimally.

Vitamin B12 and B Complex Usages

It is important to understand when to use vitamin B12 and when to use B complex depending on your symptoms.

Additionally, you should also be aware of the individual impact of these nutrients on some vital functions of your body as explained below.

B12 or B Complex For Energy

Vitamin B12 is definitely one of the most critical nutrients needed for the generation of energy in the body in the form of ATP molecules.

These molecules are released from the breakdown of glucose and help to assist cells in performing their functions.

Almost all the cells in the body use vitamin B12 for their energy needs. It can also increase energy levels by converting fats and proteins into a usable source of energy.

The deficiency of vitamin B12 can cause fatigue, weakness, tiredness, reduced focus, and anemia.

These benefits of vitamin B12 are complemented by other nutrients, especially vitamins B1 and B3.

Vitamin B1 helps to increase energy levels by converting carbohydrates and fats into glucose.

Vitamin B3 can help by boosting the body’s metabolic rate and stimulating blood flow to the organ and tissues.

This can enhance the availability of other nutrients to the cells and improve calorie utilization by the body.

B12 or B complex for Weight Loss

Vitamin B12 plays a crucial role in the metabolism of fat, indicating that the deficiency of this nutrient could lead to an accumulation of fat in the body resulting in obesity.

Severe deficiency of vitamin B12 has also been found to cause a significant rise in the percentage of body fat. It can also increase the level of cholesterol in the blood.

An adequate supply of vitamin B12, on the other hand, could prevent weight gain by inhibiting fat storage and allowing the body to convert fat to glucose to be used up for its energy needs.

It can also lower the body’s fat percentage and reduce the risk of obesity.

Vitamins B1, B5, and B6 can complement the weight loss benefits of vitamin B12 by stimulating the conversion of carbohydrates into energy.

Ensuring that your body receives a good supply of these vitamins can increase your energy expenditure and speed up weight loss.


Each of the B vitamins including vitamin B12 is essential for maintaining the overall health and wellness of a person.

These nutrients can improve fat metabolism, increase energy levels, prevent fatigue, and promote weight loss while providing several other benefits.

Patients can choose to take vitamin B12 or B complex depending on their specific symptoms that could be linked to the deficiency of these nutrients.

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  1. It's written and or reviewed by an expert.
  2. We cite relevant studies and trusted sources.
  3. It's regularly updated.

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