Your body requires a wide variety of vitamins, minerals and other nutrients to function optimally. Vitamin B-6 and vitamin B-12 are two of eight B vitamins your body needs. While these vitamins work together, they also provide their own benefits individually. If you consume a well-balanced diet, you're likely getting enough of these vitamins. A B-6 deficiency is rare, according to the Office of Dietary Supplements, but older adults and vegans are at risk of a B-12 deficiency.
A wide variety of foods supply vitamin B-6, including chickpeas, fish, potatoes, bananas, cottage cheese, poultry and meat. B-6 plays a role in cognitive function, and it is also involved in more than 100 enzyme reactions. Along with B-12, B-6 helps control homocysteine, a substance that when high is linked to an increased risk of cardiovascular disease.
You get B-12 from fish, cheese, dairy, meat and eggs, as well as from fortified cereals. Vitamin B-12 plays a crucial role in energy metabolism and the production of red blood cells. Because B-12 helps your body convert carbohydrates from what you eat into fuel, low levels of the vitamin can lead to fatigue. You also need B-12 for healthy nerve function, so a deficiency may lead to nerve damage. In addition, vitamin B-12 promotes healthy neurological function and DNA production, and it's also needed for normal brain function.