Where they do sometimes fall short is with nutrients found mainly in animal products, like vitamin B12. Vegans in particular need to look into the possibility of taking a supplement to be sure they're getting what they need.

What Does Vitamin B12 Do?

Vitamin B 12 is essential for healthy living. Its main functions involve the formation of red blood cells and the maintenance of a healthy nervous system. B 12 is necessary for the timely synthesis of DNA during cell division. This is especially important in tissues where cells are dividing rapidly, particularly the bone marrow tissues responsible for red blood cell formation.

B 12 is also important in maintaining the nervous system. Nerves are surrounded by an insulating fatty sheath which is made of a protein called myelin. B 12 plays a vital role in the metabolism of fatty acids essential to maintain healthy myelin. B 12 deficiency over a long period of time can lead to nerve degeneration and irreversible nerve damage

Reliable sources of vitamin B12 are in animal products like meat, eggs and dairy products. Some research has shown that it also occurs in some kinds of plants, such as seaweeds, an algae called spirula, and fermented soy products. However, recent studies have come to the conclusion that humans cannot process this form of the vitamin, so these are not effective sources of B12 for vegans and vegetarians.

Fortunately, a large number of cereal products are enriched with vitamin B12. Breakfast cereals are an excellent source as well as some enriched breads. By paying attention to the nutrition labels on these kinds of products, it is possible to supplement a diet that is otherwise lacking in B12.

Vitamin B12 Deficiency

How will you know if you are deficient in B12? The deficiency can take years to show up in a noticeable way, so if you develop symptoms long after your diet has changed, make sure you get your doctor to check it out. Some of the symptoms that can point to a deficiency are: dizziness, paleness, shortness of breath, fatigue, anemia and hearing problems.

These are early symptoms. If the condition remains untreated the effects are more serious. Vitamin B12 deficiency can cause progressive damage to the nervous system, especially the nerves outside the brain and spinal cord.

When the spinal cord is involved, the first symptoms include difficulty in feeling vibrations in the feet, loss of position sense, and loss of muscle co-ordination. Other advanced symptoms are weight loss, exaggerated reflexes, damage to the optic nerve, hallucinations, personality and mood changes. Eventually those suffering from a deficiency will develop an enlarged spleen and liver.

If all of that has you running out to find the biggest B12 supplement on the market, put the brakes on for a moment. A healthy, young adult should be able to get most of the B12 he or she needs by either eating animal products or enriched cereal products.

A multi-vitamin supplement which includes B12 is a good idea if your diet is limited. As you get older, your body's ability to absorb B12 from animal sources actually decreases. So supplements become more important after the age of 50.