You need to take in a well-balanced mix of nutrients to maintain optimal health, and sometimes understanding the interactions between the essential vitamins can be a bit tricky. When it comes to folate and vitamin B-12, maintaining the proper ratio of these two nutrients can prevent you from masking a potentially dangerous deficiency that can lead to nerve damage.
Vitamin B-12 is water-soluble, meaning that your body excretes any excess amounts of it in your urine. It is also an essential nutrient, meaning that your body can't create it on its own; you must consume it through dietary sources. B-12 is crucial to the formation of red blood cells, and a B-12 deficiency can lead to megaloblastic anemia, a condition wherein your red blood count becomes lower in number, while the cells themselves become larger in size. B-12 is also necessary to maintain your nervous system, and a deficiency can result in permanent nerve damage, according to the National Institutes of Health.
Folate is another B vitamin -- B-9 -- that is naturally found in food. You're probably more familiar with its synthetic form, folic acid, which is used to make supplements and it commonly recommended to women in early pregnancy to decrease the risk of neural tube defects in their unborn children. According to the Merck Manuals Online Medical Library, folate helps red blood cells mature and aids in the development of the fetal nervous system. The folate content of foods is destroyed during any prolonged cooking process, but the NIH states that a folic acid fortification program initiated in 1998 has overcome previously high deficiency rates and boosted the dietary intake of most Americans to recommended daily levels.
Deficiencies in folate or B-12 can have similar results. Both deficiencies can increase your levels of serum homocysteine, a risk factor for cardiovascular disease. Increasing your folate levels can decrease homocysteine in your blood. Unfortunately, high folate consumption can also mask a deficiency in B-12, and the NIH warns that it can also make the symptoms of B-12 deficiency worse, increasing the risk of permanent nerve damage and cognitive decline.
In order to ensure that an excess of folate is not masking a B-12 deficiency it is important to consume the correct dosages of these two nutrients. The NIH states that healthy people over the age of 19 should not take more than 1000 mcg of folate per day, while the recommended dietary allowance for B-12 in those over the age of 14 is 2.4 mcg.