1. Red Blood Cell Production: Vitamin B12 is essential for the production of red blood cells, which carry oxygen throughout the body.
2. Nervous System Function: Vitamin B12 is important for the proper function of the nervous system. It helps to maintain the myelin sheath that surrounds and protects nerve fibers.
3. DNA Synthesis: Vitamin B12 is involved in the synthesis of DNA, which is the genetic material that controls cell growth and division.
4. Energy Production: Vitamin B12 is involved in the metabolism of carbohydrates, fats, and proteins, which are used to produce energy in the body.
5. Brain Function: Vitamin B12 may help to improve cognitive function and reduce the risk of cognitive decline, particularly in older adults.

1. Animal Products: Vitamin B12 is naturally found in animal products, such as meat, fish, poultry, eggs, and dairy products.
2. Fortified Foods: Some foods, such as breakfast cereals and plant-based milk alternatives, are fortified with vitamin B12.
3. Supplements: Vitamin B12 supplements are available in various forms, including tablets, capsules, and injections.
4. Nutritional Yeast: Nutritional yeast is a deactivated yeast that is often used as a seasoning. It is a good source of vitamin B12 for vegans and vegetarians.
5. Fermented Foods: Some fermented foods, such as tempeh and miso, may contain small amounts of vitamin B12.

The recommended daily intake of vitamin B12 for adults is 2.4 mcg per day. However, higher amounts may be needed for certain populations, such as older adults and vegans/vegetarians who do not consume animal products. It’s important to obtain vitamin B12 from food sources or supplements, as a deficiency can lead to serious health problems, including anemia and neurological damage.