U.S. Department of Agriculture: Agricultural Research Service, Lincoln, Nebraska


Date of this Version


Document Type



Agricultural Research April 2013


Vitamin B12 helps your body perform many vital chores, including forming healthy red blood cells; keeping your brain functioning smoothly; and processing (metabolizing) the fats, proteins, and carbohydrates in foods that you eat.

Like all vitamins, B12 is a micronutrient, meaning that we need it in only very small amounts. We get B12 from animal products— meats, fish, poultry, eggs, cheese, and yogurt, for instance—or from B12-fortified foods, notably breakfast cereals. We can also obtain it from nutritional supplements, such as B12 tablets or multivitamin pills. People who need to boost their B12 levels quickly may do so via shots or other means prescribed by their physicians.

In the United States, the very young and the elderly are among the groups at risk of becoming B12 deficient. Newborns whose mothers are deficient in the vitamin may begin their lives with low stores of it. The problem may be compounded if these babies are breastfed, because the B12 levels in their mother’s milk may be inadequate.

Seniors may have a different set of problems. If they lack sufficient gastric acid in the stomach, for instance, they may be unable to absorb enough of the vitamin from their food.

Now, a team of Agricultural Research Service scientists based at the Western Human Nutrition Research Center in Davis, California, has developed and tested an improved method for measuring a marker, or indicator, of the body’s stores of B12 in blood. Importantly, the blood sample can be very small in volume.

That’s an advantage in both medical and research situations. For example, samples that are taken from newborns and infants for health examinations at a hospital, or perhaps for use by medical or nutrition researchers, are typically very small.