What is Vitamin B12?
"Vitamin B12 is a water-soluble vitamin of the vitamin B group. It is present in some foods, added to others and is available as a dietary supplement – either on its own or in a multivitamin and multimineral product," says Dietitian Dr Carrie Ruxton from the Health & Food Supplements Information Service. "It is required for the development and health of nerves and red blood cells, for DNA synthesis. B12 also helps with the activity of several enzymes involved in metabolism.
What are the benefits of Vitamin B12?
Vitamin B12 (alongside other nutrients such as iron) helps to ensure that you have healthy red blood cells and healthy body cells (cells other than blood cells). "Alongside other B vitamins, it helps to ensure that energy is released from the food you eat. It also helps (alongside many other vitamins and minerals) to keep your immune system healthy and functioning well," says Dr Carrie.
What are the sources of Vitamin B12?
"Vitamin B12 is found only in animal products and certain foods fortified with the vitamin. Good sources include meat, liver, kidney, poultry, fish, eggs, dairy products and fortified breakfast cereals," explains Dr Carrie. "Labels should be checked for the vitamin B12 content in, for example, breakfast cereals, as not all breakfast cereals contain the vitamin."
One way to ensure that you get enough B12 is to take a supplement. Increasing numbers of people are eating more plant-based diets or reducing their intake of animal foods so it is recommended to supplement with B12 to be sure of getting enough.
Who is at risk of Vitamin B12 deficiency?
"Older people are commonly at risk of vitamin B12 deficiency. This is because vitamin B12 requires a substance known as extrinsic factor found in the stomach acid for its absorption," Dr Carrie says. "Older people often have a lack of stomach acid and hence have a difficulty in absorbing B12. Some medications such as proton pump inhibitors (e.g. omeprazole) which inhibit gastric acid can reduce the absorption of vitamin B12. Metformin which is commonly used in the management of diabetes mellitus can also reduce the absorption of vitamin B12.”
Symptoms of vitamin B12 deficiency
Symptoms of vitamin B12 deficiency tend to develop gradually and are wide-ranging. They can include:
• Extreme tiredness
• Lack of energy
• Disturbed vision
• Psychological problems, such as depression and confusion
• A sore tongue
• Problems with memory