Sublingual vitamin B12 is merely a form of the vitamin that is taken under the tongue. The advantage of sublingual vitamins is improved absorption. In the case of B12, this method of administration is often better for seniors who frequently have trouble absorbing the vitamin from the stomach.
Regardless of the form it comes in, vitamin B12 is used to treat pernicious anemia, a much different condition from the more common iron-deficiency anemia. If your niece has pernicious anemia, she needs B12 - not iron. If she has iron-deficiency anemia, she needs iron, not B12. Pernicious anemia is due to vitamin B12 deficiency and is rare in young people - except in strict vegetarians (vegans) who eat no animal products, our only dietary source of B12. The condition can also occur in older men and women who lack sufficient "intrinsic factor," a protein produced in the stomach that is necessary for B12 absorption (which occurs in the small intestine). Failure to produce intrinsic factor can be genetic in origin or caused by atrophy of the stomach lining (common in older age), or by autoimmunity.
Mild to moderate cases of iron-deficiency anemia can be treated with an over-the-counter iron supplement. My personal preference is Floradix, a natural product. If your niece is having trouble taking an iron supplement, she can try the suggestions below for obtaining more iron from her diet:
- Cook in cast-iron pots (the cooked food absorbs iron and delivers it to you).
- Increase your intake of red meat, chicken and fish, all of which provide some iron. Vegetarian sources include whole grains, dried beans, molasses, dried apricots and prunes, and leafy green vegetables such as kale, beet greens and chard, as well as exotic greens such as dandelions, lamb's quarters, nettles and yellow dock.
- Eat more foods that enhance iron absorption. These include fruits and vegetables high in vitamin C, or yogurt or sauerkraut, both of which contain lactic acid, which promotes iron absorption. Fermented soy foods can help, too.
- Avoid caffeinated beverages, eggs, milk and bran, all of which can interfere with iron absorption.
If her physician has prescribed iron and your niece can't handle the supplement, she should be sure to let the doctor know if she stops taking it and is trying to increase her iron stores via the steps outlined above. These may not be adequate if she is severely anemic.
Andrew Weil, M.D.