Safety and side effects
Vitamin B12 is found in animal foods, as well as some fortified foods that have added B12. Fortified foods vary from country to country, but often include milk alternatives or breakfast cereals.
Some especially good sources of vitamin B12 include:
· Liver: 1/3 cup (75g) provides 881% of the RDI
· Beef kidney: 1/3 cup (75g) provides 311% of the RDI
· Trout: 1/3 cup (75g) provides 61% of the RDI
· Canned salmon: 1/3 cup (75g) provides 61% of the RDI
· Ground beef: 1/3 cup (75g) provides 40% of the RDI
· Eggs: 2 large eggs provides 25% of the RDI
· Milk: 1 cup ( 250ml ) provides 20% of the RDI
· Chicken: 1/3 cup (75g) provides 3% of the RDI
It can be difficult for some people to meet their vitamin B12 requirements. This is particularly true for those following a vegetarian or vegan diet. In these situations, it’s usually recommended that you supplement you diet with either a B12 shot or oral supplement. Fortunately, there is increased evidence that oral B12 supplements are just as good as injections for raising blood levels in most people. Vegetarians and vegans are usually advised to take at least 10mcg per day, or at least 2,000 mcg once per week. However, some still prefer the use of injections.
Do you need vitamin B12 injections?
If you eat a well-balanced diet that includes foods rich in vitamin B12, then it is unlikely that you’ll need to take additional B12. For most people, dietary sources provide everything that is needed. However, people who are at risk of deficiency will probably need to take supplements or have regular injections to keep their levels up.
Why is vitamin B12 Necessary?
Vitamin B12 is a nutrient that helps keep the body’s nerve and blood cells healthy and helps make DNA, the genetic material in all cells. Vitamin B12 also helps prevent a type of anaemia called megaloblastic anaemia that makes people tired and weak.
Two steps are required for the body to absorb vitamin B12 for food. First, hydrochloric acid in the stomach separates vitamin B12 from the protein to which vitamin B12 is attached in food. After this, vitamin B12 combines with a protein made by the stomach called intrinsic factor and is absorbed by the body. Some people have pernicious anaemia, a condition in which they cannot make intrinc factor. As a result, they have trouble absorbing vitamin B12 from all foods and dietary supplements.
What happens if I don’t get enough vitamin B12?
Vitamin B12 deficiency causes tiredness, weakness, constipation, loss of appetite, weight loss, and megaloblastic anaemia. Nerve problems, such as numbness and tingling in the hands and feet, can also occur. Other symptoms of vitamin B12 deficiency include problems with balance, depression, confusion, dementia, poor memory, and soreness of the mouth or tongue. Vitamin B12 deficiency can damage the nervous system even in people who don’t have anaemia, so it is important to treat a deficiency as soon as possible. More on this further down.
In infants, signs of a vitamin B12 deficiency include failure to thrive, problems with movements, delays in reaching the typical development milestones, and megaloblastic anaemia.
Large amounts of folic acid can hide a vitamin B12 deficiency by correcting megaloblastic anaemia a hallmark of vitamin B12 deficiency. But folic acid does not correct the progressive damage to the nervous system that vitamin B12 deficiency also causes. For this reason, healthy adults should not get more than 1,000 mcg of folic acid a day.