Diet plays a major role in the maintenance of good health. Vitamins B9 (folate) and B12 (cobalamin) are important in this respect as they help to maintain homocysteine within a reference range so that it does not detriment health. The human body will require a balanced level of folate, vitamin B12 and homocysteine for the body to stay healthy. Health issues can occur when these levels are not regulated and fall outside of the reference range. This essay will focus on the effects of vitamin B12, B9 and homocysteine on health.
Folate is a form of a water-soluble B vitamin, obtained from natural source of food such as leafy green vegetables and fruits. Folic acid is a synthetic form of the same vitamin that is found in supplements. Folate is essential in most type of body functions including; producing DNA, repairing DNA, and aiding the production of erythropoiesis. Also, have the ability to interact with other vitamins to catalyse the cell’s metabolism and this interaction can influence cellular metabolism and human reproduction. This is a combination of reactions that occurs in every cells to regulate metabolic pathway that is sustained by homeostasis. (7) Folate have another important role in the immune system by supporting white blood cells to destroy pathogens. (1)
A sufficient supply of folate is required to limit the chance of cell mutation, genetic disorders and tumour growth. The daily intake reference range of folate is approximately 100-200mg. According to an article published by University of Maryland Medical Centre, researchers stated that they are unclear on how low levels of folate affect the likelihood of developing a tumour. But, other researchers think that people who have the correct amount of folate will maintain the healthiness of DNA, therefore avoiding mutations. (10)
Low levels of folate can lead to disorders such as birth defects, and stunted neonatal growth. Low levels could reveal an inactivating mutation in the methylene-tetradrofolate reductase, and that homocysteine levels will rise and methionine will reduce. (2) Low levels of folate also can have an effect on the structure of red blood cells, causing abnormally large and deformed cells. Vitamin deficiency can occur when the person do not consume enough vitamins.
A reduced level of folate during pregnancy can cause malformation of the unborn baby. Problems may include deformity of the heart and limbs. Since folate is required for DNA duplicating and building new cells, low levels can lead to developmental complications of the unborn baby. (3) Folate coenzymes are required for digestion of amino acids, histidine, cysteine, serine, glycine, and methionine. The synthesis of methionine from homocysteine will be catalysed by methionine, this enzyme require both folate and vitamin B12. Implying that low levels of vitamin B12 and B9 can prompt a reduced methionine and build-up of homocysteine. An increased concentration of homocysteine may allow the patient to experience chronic diseases. (11)
An increased levels of folate usually does not cause serious problems. However, high levels of folate and low levels of vitamin B12 could suggest that the patient experiencing vitamin B12 deficiency, unless folate supplements are taken at high dose to prevent this problem. Since vitamin B12 is required for the formation of active form of folate, deficiency of both will lead to anaemia. Thus at high intake of folate, anaemia may not occur and the person may not be diagnosed with vitamin B12 deficiency.
Vitamin B12 is vital for the body as it aids in the production of healthy red blood cells. Red cells contain a specialised haemoglobin molecule that transport oxygen around the body to supply energy for tissues or muscles. (4) People who are considered to have vitamin B12 deficiency will have a lower level of vitamin B12 compared to a heathy person. The normal range of vitamin B12 is 200 – 500 pg/mL. Therefore, people with vitamin B12 deficiency will have <200 pg/mL. (5) Vitamin B12 deficiency causes the body to feel tired as lack of healthy red cells are available in the body, meaning that the body cannot function correctly as cells will receive less amount of oxygen. According to an article on ConsumerLab, a pregnant woman who takes extremely high levels of vitamin is at greater possibility of having a child with autism spectrum. Also, high levels of the vitamin can cause kidney problems, and increase the chance of heart attack. (9) Homocysteine (HCU) is an amino acids that are made up of building blocks of proteins. The break down of proteins in the body determines the level of homocysteine. An imbalance level of homocysteine can lead to conditions, such as hyperhomocysteinemia and homocystinuria. The reference range of Homocysteine: age 0-30 years: 4.6-8.1 µmol/L age 30-59 years: 6.3-11.2 µmol/L (males); 4-5-7.9 µmol/L (females) age >59 years: 5.8-11.9 µmol/L. (12) Hyperhomocysteinemia is related to the elevated level of homocysteine. This can lead to cardiovascular disease, usually associated with the build-up of fatty deposit in arteries (atherosclerosis). (8) Which can restrict the flow of blood away from the heart.
Vitamin B9 and vitamin B12 are closely connected in cell differentiation. Vitamin B12 will interact with other types of vitamins to produce methionine. In this case, vitamin B12 reacts with vitamin B9 to activate folate. This is achieved by conducting reactions to produce acid derivative. Tetrahydrofolate is an active form of vitamin B9 and is known as 5-methyltetrahydrofolate. 5-methyltetrahydrofolate releases their methyl group to vitamin B12 (cobalamin), this procedure allows it to become methylcobalamin. The methylcobalamin then gives its methyl group to homocysteine, so that it can be converted in to methionine. (14) The reaction of cobalamin with 5-methyltetrahydrofolate result in the production of homocysteine to methionine. Which, this is very important in metabolic processes. Methionine can then react further in the process to form S-adenosylmethionine. During this reaction, S-adenosylmethionine release its methyl grough for it to become homocysteine. This is important role in the production of neurotransmitters and methylation of DNA. (6)
Folate (vitamin B6), vitamin B12 and homocysteine are all found in the blood and requires regulation. The body needs to acquire a normal range of the vitamins and homocysteine in order to stay healthy and to aid haem synthesis. High homocysteine levels are caused by the lack of folate and cobalamin. If the levels are not regulated then it will cause problems, and develop unwanted conditions. Intakes of the correct amount of food and the correct level of vitamins avoids complications.