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What is Vitamin B12 and why is it so important?

23 Nov 2022 • 1 min read

Vitamin B12 is one of eight B vitamins that have a vital role in keeping our bodies in tip-top condition. B12 is arguably the most important; from fighting fatigue and keeping our bodies’ nerve and blood cells healthy to producing DNA. Here we uncover the benefits of this important vitamin.

Where can I find B12?

Your body doesn’t make Vitamin B12, so it’s important to get it from a balanced diet. Beef, pork, eggs, milk, cheese and fish are all good sources of B12. If you're vegetarian or vegan, it may be that you aren’t able to get enough B12 as you are excluding those food groups. B12 can be found in some breakfast cereals and nutritional yeasts in in supplements. Handpicked article: Essential nutrients for Vegans Shop Vitamin B12

What happens if I don’t get enough B12?

The NHS recommends adults to have at least 1.5mcg of B12 a day. This is easily achieved through your diet as the body can’t product B12 itself. If you aren’t able to reach these levels, you are at risk of a deficiency. A deficiency in B12 can lead to a condition called Anaemia. This is where you have fewer red blood cells than normal and you may experience these symptoms;
  • Extreme tiredness
  • Lack of energy
  • Feeling faint
  • A pale yellow tinge to your skin
  • Sore red tongue
If you do experience any of these symptoms, you should visit your doctor for a blood test.

What does B12 help with?


B12 contributes to the production of red blood cells which carry oxygen all around our bodies. Oxygen travels from your lungs into the blood and flows to all your vital organs: brain, lungs and muscles. If these organs do not receive enough oxygen, they’ll slow down and you’ll experience fatigue and tiredness.


B12 is thought to aid with the digestion and absorption of macronutrients. Fats, proteins and carbohydrates are all metabolised by B12 into energy. Without the right amount of B12 in your diet, vital nutrients will not pass through your body and not absorb into the blood – causing deficiencies.


B12 contributes to the normal functioning of the nervous system, so may aid with the reduction in the effects of stress and anxiety on the body. It's needed for the proper development and functioning of the brain which may also aid with ailments such as stress and anxiety. Shop Vitamins
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