Our friend Dr. Williams recently wrote about vitamin B and it’s potential in helping to prevent dementia and Alzheimer’s disease. If you read it, you may have wondered—am I getting enough?
According to recent studies, many people over the age of 50 lack enough stomach acid to adequately absorb vitamin B-12. According to the 2001-2004 National Health and Nutrition Examination Survey, 3.2 percent of those over 50 have true B12 deficiency, but up to 30 percent are at risk because of a lack of stomach acids. Since the vitamin is also found naturally only in animal products, vegetarians and vegans can also be at risk of deficiency.
Here’s some more on this important nutrient, and how to tell if you may need to have your blood levels tested.
Is Your Vitamin B12 Absorbed?
As Dr. Williams mentioned, vitamin B12 is crucial to keeping the brain healthy, and it’s also critical to the health of just about every cell and system, including the blood and nervous system. The liver stores it for us, so even when we don’t get it every day, we usually aren’t at risk of deficiency for awhile.
The trick with vitamin B12, however, is absorption. The stomach has to secrete enough acid plus the digestive enzyme “pepsin” to extract vitamin B12 from food. Once it’s free, the nutrient has to combine with a protein known as “intrinsic factor” secreted by the stomach lining, which protects it while it’s transported to the small intestine for absorption.
That means we have to have a healthy stomach and a well-functioning pancreas (which produces the digestive enzymes) in order to properly absorb vitamin B12.
The following factors can contribute to poor absorption of this vitamin:
- Age over 50 (if there aren’t enough stomach acids)
- Heavy drinking (leads to inflammation of the stomach, affecting digestion)
- Poor diet
- Unhealthy gastrointestinal system
- Problems with the pancreas
- Pernicious anemia (condition that produces a lack of intrinsic factor)
- Surgery that removes part of the stomach or small intestine
- Inflammatory bowel disease
- Autoimmune disorders
- Long-term use of acid-reducing drugs (like Nexium, Pepcid, and Zantac)
- Long-term use of the diabetes drug “metformin” (Glucophage)
- Vegetarianism or veganism
- Babies whose mothers are vegetarians or vegans
Symptoms of Vitamin B12 Deficiency
If you have any of the health factors listed above, you may want to get a blood test to be sure you’re getting enough vitamin B12. A deficiency can lead to vitamin B12 deficiency anemia, however, which can produce some symptoms, including:
- Pale skin
- Shortness of breath
- Unsteady gait
- Weakness, dizziness, light-headedness
- Rapid heartbeat
- Sore tongue
- Stomach upset
- Unexpected weight loss
- Diarrhea or constipation
- Easy bruising or bleeding, including bleeding gums
Left untreated, a vitamin B12 deficiency can lead to nerve damage, mood changes, memory loss, and dementia.
Tips to Increase Absorption
If you take a blood test and your doctor finds you’re deficient in vitamin B, you may be prescribed supplements or injections, though recent evidence indicates that under-the-tongue tablets or skin patches may work as well as injections.
Those who are diagnosed as deficient are usually prescribed a daily supplement of 2,000 micrograms (mcg), which is lowered to 1,000 after about a month, then again lowered again after another month to 1,000 mcg a week.
Currently, the recommended daily allowance (RDA) for vitamin B12 is 2.4 mcg a day for those under the age of 50, and 6-15 mcg/day for those over 50. Pregnant women have a slightly higher recommendation of 2.6, and 2.8 when breastfeeding. The Mayo Clinic adds that supplementation of 25-100 mcg/day has been used to maintain appropriate levels in older people.
To improve your absorption of the vitamin, try these tips:
- Food: Increase your intake of meat, poultry, fish, eggs, and dairy.
- Alcohol: Don’t consume more than the recommended intake of one serving per day for women, and two for men.
- Supplements: If you don’t regularly consume foods that are good sources of vitamin B, consider a daily dietary supplement. If you’re not absorbing the vitamin from the pill, consider an “under-the-tongue” or “sublingual” variety, which may absorb better.
- Drink cranberry juice: A study published in 2005 indicated that eating cranberries or drinking cranberry juice may help increase the absorption of vitamin B12. Cranberry capsules at doses of 300 to 1,200 mg per day may also work. To make your own cranberry juice, use a pound of cranberries to a quart of water, and sweeten to taste. (Boil the cranberries until they burst, adding in a little honey if desired, strain, boil again to thin out the remaining pulp, add water if needed to thin, pour into a jar, and allow to cool.)
- Spice it up: One study suggested that “piperine,” a component in black pepper, may help enhance the absorption of nutrients like vitamin B.
- Calcium: Calcium is necessary for vitamin B12 absorption, so make sure you’re getting enough of this nutrient, as well. A 2000 study found, for instance, that those patients taking the diabetes medication metformin, which inhibits vitamin B absorption, were able to reverse low vitamin B12 levels by upping their calcium intake.
- Consider caffeine: Caffeine stimulates the production of stomach acid, which helps the body absorb vitamin B12. Just be careful not to consume too much, as then you may experience other symptoms, such as headaches, dizziness, and edginess.
Do you have other tips for increasing the absorption of vitamin B12? Please share.
* * *
“Don’t B Deficient,” University of California Berkeley Wellness Letter, April 2013.
Bacon F. Chow, et al., “Factors Affecting the Absorption of Vitamin B12,” The American Journal of Clinical Nutrition, July-August 1958, http://ajcn.nutrition.org/content/6/4/386.full.pdf.
Marvin M. Lipman, “Vitamin B12: Panacea or placebo?” Consumer Reports on Health, February 2012.
Patrick Massey, “Cranberries Might Increase the Absorption of Vitamin B12,” Daily Herald, November 21, 2005, http://www.newmediaexplorer.org/chris/2005/11/21/cranberries_might_increase_the_absorption_of_vitamin_b12.htm.
“Piperine,” Quest Health Library, http://www.questhealthlibrary.com/herbs/piperine.
W A Bauman, et al., “Increased intake of calcium reverses vitamin B12 malabsorption induced by metformin,” Diabetes Care, September 2000, 23(9):1227-1231, http://care.diabetesjournals.org/content/23/9/1227.