B-12 Facts.....

Vitamin B12 is needed for manufacture of red blood cells (along with
folic acid). B12 helps the body's use of iron and is also required
for proper digestion, the absorption of foods, the synthesis of
protein and the metabolism of carbohydrates and fats. No wonder it's
important for good energy levels! It is often observed that taking
B12 (especially via injections) reduces fatigue, even when a
deficiency isn't found.

B12 deficiencies are common due to declining B12 levels in food,
increased use of antibiotics and digestive problems. This is because
B12 is produced in the digestive tract as well as being absorbed from
food. Those most at risk of a B12 deficiency are vegetarians and
people with digestive disturbances.

Symptoms of deficiency: fatigue, weakness, dizziness, sore tongue,
memory problems, confusion, irritability, depression, moodiness,
paleness.

Testing for deficiency: B12 levels can be measured with a blood test


What is the health risk of too much vitamin B12?
The Institute of Medicine of the National Academies did not establish
a UL for this vitamin because vitamin B12 has a very low potential
for toxicity. The IOM states that "no adverse effects have been
associated with excess vitamin B12 intake from food and supplements
in healthy individuals" [7]. In fact, the IOM recommends that adults
older than 50 years get most of their vitamin B12 from vitamin
supplements or fortified food because of the high incidence of
impaired absorption in this age group of vitamin B12 from foods that
come from animals [7].