When to take Vitamin B12 (Cobalamin)

What is vitamin B12 (Cobalamin) good for?

Short answer: Vitamin B12 has potential benefits for energy levels, cardiovascular health, bone health, depression, pregnancy, eye health and mental health.

Vitamin B12, also known as cobalamin, is an essential vitamin that ensures your body's nervous system and red blood cells remain healthy and functional, and it also assists in the synthesis of DNA, the genetic building block of every cell in your body.

Role in mental health

Vitamin B12 deficiency has been found to cause cognitive issues such as memory loss, especially in the elderly, and a study in 2019 found that B vitamins have an effect on our mood and on our ability to handle stress, both in healthy individuals and in people who suffer from mental health conditions.

Furthermore, a review in 2020 found that lower levels of vitamin B12 are directly linked to a higher risk of depression.

Benefits for red blood cell health

In terms of physical health, low levels of vitamin B12 are associated with a reduction in red blood cell formation, and also a reduction in the overall health of the red blood cells that are produced. Specifically, they change from the typical round representation we are familiar with to a more oval-shaped cell, as a result of their degraded quality.

Vitamin B12 plays a crucial role in the structure and quality of red blood cells.

Role in bone health

There is also an emerging link between vitamin B12 deficiency and poor bone health, including an increased risk of osteoporosis and fracture, due to the role vitamin B12 plays in maintaining bone density.

Importancy during pregnancy

And perhaps most importantly of all, decent levels of vitamin B12 are crucial for a healthy pregnancy, as low vitamin B12 levels in the early stages of pregnancy can increase the risk of birth defects, premature birth, or even miscarriage.

When should I take vitamin B12?

Short answer: Vitamin B12 is best taken first thing in the morning on an empty stomach, at least 30 minutes before breakfast.

Vitamin B12 is one of several water-soluble vitamins, which means that you only need water in order to absorb them efficiently, preferably on an empty stomach to maximize absorption.

Due to its energizing properties and role in blood oxygenation, the ideal time to take vitamin B12 would be first thing in the morning, just after waking up, before breakfast.

What does vitamin B12 combine well with?

Short answer: Vitamin B12 has been shown to work well together with astaxanthin, fish oil, garlic extract, krill oil, L-arginine, omega-3, ubiquinol, vitamin B1, vitamin B6, vitamin B9 and vitamin D.

Vitamin B12 with omega-3

While vitamin B12 is rather different from omega-3 supplements, such as fish oil and krill oil, some studies find that taking vitamin B12 together with this type of supplement can help enhance the activity of both.

Vitamin B12 with ubiquinol, astaxanthin & vitamin D

There are other similar combinations that are being studied. For example, vitamin B12 combined with ubiquinol, astaxanthin and vitamin D could potentially enhance energy deficiencies, athletic performance and muscle health, especially in people who follow a vegan or vegetarian diet that is naturally poor in such nutrients.

Vitamin B12 with folic acid, garlic extract & L-arginine

On the topic of heart health, one study showed that a combination of vitamin B12 with vitamin B9 (folic acid), L-arginine and aged garlic extract significantly reduced the progression of atherosclerosis and improved vascular function.

Vitamin B12 with other B vitamins

B vitamins not only enhance each other's functions, but also depend upon one another for optimal absorption. Studies have shown that a combination of vitamins B1, B6, B9 and B12 are effective in treating episodic migraines and vertebrae-related back pain, as one example.

Also, vitamin B9 (folic acid) and vitamin B12 work together to produce the compound S-adenosylmethionine, which is involved in immune system function and also in mood regulation.

Another example is the combination of vitamins B6, B9 and B12, which work together to control blood levels of homocysteine, an amino acid which is associated with heart disease when found in high levels in the blood.

What should I avoid taking vitamin B12 with?

Short answer: Avoid taking vitamin B12 supplements at the same time as spirulina or vitamin C.

Avoid with vitamin C

Taking vitamin B12 with vitamin C has been known to reduce bioavailability of vitamin B12, so in order to avoid this interaction, it is recommended to take vitamin C and vitamin B12 at least two hours apart.

Avoid with spirulina

Also, it is not recommended to take spirulina together with vitamin B12 supplements. A study found that taking spirulina significantly reduced vitamin B12 levels in participants, and this is because the vitamin B12 "analogues" that are found in spirulina can actually hinder absorption of the real vitamin B12.

This is why spirulina products are no longer allowed to be marketed as sources of vitamin B12, and it is also why vegans and vegetarians, along with people who have issues with vitamin B12 absorption, are advised to avoid taking spirulina products altogether.

What are natural sources of vitamin B12?

If you are interested in achieving your daily vitamin B12 intake through your diet, rich sources of vitamin B12 include:

Lamb liver
Beef liver
Beef
Clams
Tuna
Salmon
Trout
Sardines
Eggs
Milk
Cheese
Yoghurt

Vitamin B12 data sources & further reading

Last updated by Asklepios on 30th January, 2025