Couldn't find what you looking for?


Vitamin B12 (cobalamin) is one of the essential vitamins for the human body. It participates in cellular metabolism and is crucial for production of red blood cells. Insufficient intake of vitamin B12 can cause a specific type of anemia called megaloblastic anemia. Furthermore, this particular vitamin is in charge of many functions related to the brain and nervous system in general.

Vitamin B12 can be easily obtained from many foods. It is abundant in meats and various dairy products. If necessary the vitamin can be taken in a form of supplements. However, only a doctor can decide whether a person needs to take vitamin B12 supplements and determine the exact daily dose. Any excess of vitamin B12 taken in a form of supplement can be detrimental and cause many side effects.

Vitamin B12: Side Effects

The most frequent side effects of vitamin B 12 include itching, swelling and a variety of skin rashes. These skin changes may linger for months after the end of the treatment. In case skin changes become severe a person requires prompt medical attention. Apart from skin changes excess of vitamin B 12 may also cause diarrhea, chest pain, breathing difficulties, heart palpitations, insomnia, anxiety, panic attacks etc. People allergic to cobalt are not supposed to take vitamin B12 supplements.

Toxicity of Vitamin B12

Being a water-soluble vitamin, excessive intake of vitamin B12 generally does not cause toxic effects. Its water-solubility allows the excess of vitamin B12 to be excreted via urine and some of it is also eliminated with stool. However, elimination of excess of vitamin B12 is possible to certain extent.

Substantial increase of vitamin B12 in the body is associated with the occurrence of different types of cancers and several more illnesses.

Vitamin B 12 is related to certain cancers. If it is taken in a form of supplements, vitamin B12 can successfully activate cell division. So if there is a malignant tumor in the body the vitamin will actually accelerate the growth of the tumor and may also speed up its spread. Some people suffering from certain illnesses require prolonged treatment with vitamin B12 supplements. These include patients with pernicious anemia. Prolonged intake of vitamin B12 supplements in these patients can cause leukemia. Increased level of vitamin B12 is also a risk factor for prostate cancer. And finally, excessive intake of vitamin B12 and a diet rich in cholesterol and animal proteins are huge risk factors for stomach and esophageal cancer.

Uncontrollable intake of vitamin B12 can additionally cause increase in overall volume of blood and in some cases it can induce excessive clotting of the blood. If it is used in treatment from megaloblastic anemia, vitamin B12 may induce hypokalemia and gout.

Due to all the previously mentioned facts it is essential to consult a doctor prior taking vitamin B12 supplements. And finally, even if supplements are recommended a person should stick to the prescribed dose and never exceed it.

Your thoughts on this

User avatar Guest