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What is Vitamin B12?

What is Vitamin B12?

Vitamin B12 is essential for keeping the body functioning properly. It aids in producing red blood cells and helps keep nerves healthy while playing a role in many other processes. Despite its importance, many people don’t know enough about vitamin B12, which is why we’ve created this blog post to help you understand everything you need to know about it.

What is vitamin B12?

Vitamin B12, also known as cobalamin and is one of the eight B vitamins. It is a water-soluble vitamin, meaning the body does not store it. Vitamin B12 plays an important role in many bodily functions:

  • Healthy nerve cell function
  • Red blood cell production
  • DNA synthesis

Working with Vitamin B9 (also called folate or folic acid) helps regulate levels of homocysteine in the blood. Homocysteine is an amino acid produced by the body during protein breakdown processes. High homocysteine blood levels can put you at risk of having heart problems or a stroke. Vitamins B6, B12 and B9 work together to promote normal homocysteine levels in your blood. B12 and B6 are necessary for activating Vitamin B9 to break down homocysteine in your body. It’s important to ensure you’re getting enough of these vitamins regularly through diet or supplementation, to protect your cardiovascular health.

Symptoms of vitamin B12 deficiency

Signs and symptoms of low vitamin B12 levels may include:

  • Megaloblastic anaemia
  • Fatigue
  • Palpitations
  • Pale or yellowish skin
  • Depression
  • Memory loss
  • Weight loss
  • Digestive upsets such as bloating, gas or constipation
  • Infertility

Other less common symptoms can include nerve damage, which often leads to tingling and numbness in the hands and feet, as well as difficulty walking. Loss of balance could also occur due to the lack of vitamin B12. If these symptoms are ignored or left undiagnosed and untreated, it can increase the risk of cardiovascular disease and serious neurological symptoms over time. Recognising early signs and conditions of vitamin B12 deficiency is key to avoiding potential long-term health issues and ensuring you stay healthy in the future.

Risk Factors for Vitamin B12 deficiency

Vitamin B12 is a nutrient that helps your body grow and develop, so getting enough of it in your diet is important. Some people are at an increased risk of deficiency of this essential vitamin than others:

  • Those with pernicious anaemia, which is an autoimmune disorder, are more prone to having a deficiency, since they have trouble absorbing B12 from their food
  • Older adults often suffer from impaired digestion and absorption, affecting around 1 in 10 people aged 75 or over and 1 in 20 aged 65 to 74
  • Vegetarians and vegans often miss out on getting enough B12 since it is only found naturally in animal products, even though there are some fortified foods containing it
  • People with medical conditions that affect the small intestine, like Coeliac disease and Crohn’s disease
  • People infected with Helicobacter pylori, an organism in the intestines that can cause an ulcer. H. pylori damages stomach cells that make intrinsic factor, a substance the body needs to absorb B12
  • Pregnant women
  • Those taking certain medications, such as metformin and proton pump inhibitors
  • Individuals with HIV/AIDS
  • Alcoholics

If you have any of these risk factors, it may be important for you to discuss your levels of Vitamin B12 with your doctor. They can determine if supplementation with foods or supplements could help prevent low levels of vitamin B12, potentially leading to long-term health problems if uncontrolled.

What foods contain vitamin B12?

Animal sources of vitamin B12

If your body is low in vitamin B12, animal foods are a great way to boost your vitamin level. Animal products are rich in this nutrient and provide us with a great source of dietary vitamin B12. Food sources include:

  • Animal meats, such as beef, pork, poultry and fish
  • Animal milk and dairy products, such as cow’s milk, yoghurt, cheese and cream
  • Eggs
  • Animal-based seafood such as oysters, mussels or shrimp

Animal sources of vitamin B12 are a reliable way to get enough of this essential vitamin in your diet.

Non-animal sources of vitamin B12

Follow a vegan diet or vegetarian diet. You may be aware that vitamin B12 is found almost exclusively in animal products and therefore, can be much harder to get into the diet. Don’t worry, because non-animal sources of vitamin B12 do exist.

  • Nutritional yeast is an effective source and can be easily added to dishes such as salads or pasta sauces
  • Fortified foods such as breakfast cereals, non-dairy milk, certain non-dairy yoghurts and cheese

Additionally, many vegan multivitamins come with added sources of B12, making it easier to get your daily recommended amount each day.

How much vitamin B12 should I take?

The NHS advises that the recommended daily amount (RDA) is 1.5 micrograms (mcg) for adults (aged 19 to 64). The RDA will differ for breastfeeding and pregnant women.

How do you treat Vitamin B12 deficiency?

Treating Vitamin B12 deficiency begins with regular medical checkups and blood tests to monitor your levels. If you are found to be deficient, your doctor may recommend different treatments. Two types of treatments are available: dietary supplements and prescription medications.

Taking a dietary supplement is one option that can be purchased over the counter at your local pharmacy. Dietary supplements can include high doses of vitamin B12 taken orally or as an injection. However, if the vitamin B12 deficiency is caused by other underlying medical conditions like an intestinal disorder, your doctor might recommend a prescription medication such as cyanocobalamin or hydroxocobalamin.

Additionally, a healthy diet rich in vitamin B12 will play an important role in managing symptoms and ensuring that you receive adequate amounts of the vitamin in your diet.

Whichever option your health care professional recommends, both can be effective in correcting any deficiencies you may have and should be enough to bring your energy levels back up.

Can you overdose on vitamin B12?

While it’s a great idea to make sure you’re getting enough vitamin B12 through diet or supplements, it’s important to recognise that too much can cause side effects. Though uncommon due to the low toxicity level of B12, overdosing on this vitamin can lead to nausea, headaches, abdominal pain or even allergic reactions when taken in very large doses.

If you’re considering taking a supplement or multivitamin containing additional B12 doses over the recommended daily allowance (RDA), talk with a healthcare professional and pay attention to the amount given in each dose.

Complications of vitamin B12 or folate deficiency anaemia

Vitamin B12 or folate deficiency anaemia can cause several complications, especially if left untreated.

  • The brain and nervous system may be affected in some way. This includes fatigue, pins and needles and difficulty with balance
  • In rare cases, vitamin B12 deficiency may confuse problems with cognitive function and dementia
  • A lack of folate or B12 can lead to irregular heart rhythms, which could slow the heart rate and lead to other heart complications such as palpitations
  • In pregnant women, an unbalanced level of B vitamins can increase the chances of congenital disabilities and other health risks for the baby

Speak to a healthcare professional

Understanding what vitamin B12 does and how much we need can help us make sure we’re getting enough of this essential nutrient from our diets, supplements or vitamin B12 injections if needed. While deficiency symptoms can range from mild to severe depending on individual circumstances, having adequate amounts of this nutrient can help us stay healthy overall. Talk with your pharmacist or doctor if you have questions about Vitamin B12.



Medical Disclaimer

NowPatient has taken all reasonable steps to ensure that all material is factually accurate, complete, and current. However, the knowledge and experience of a qualified healthcare professional should always be sought after instead of using the information on this page. Before taking any drug, you should always speak to your doctor or another qualified healthcare provider.

The information provided here about medications is subject to change and is not meant to include all uses, precautions, warnings, directions, drug interactions, allergic reactions, or negative effects. The absence of warnings or other information for a particular medication does not imply that the medication or medication combination is appropriate for all patients or for all possible purposes.

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