B12 Deficiencies

Wow, I didn't realize so many people were lacking in vitamin B12. I found an article that talks about how B12 is absorbed, and that the only good natural source is meat. However, it also says that we absorb the supplement form much better. Are people just not taking their daily vitamins?

Studies have found that 20% of Americans ages 65 and over have low levels of the vitamin in their blood... More serious shortages can result in dementia or anemia, because B12 is essential for the production of red blood cells in the bone marrow. Breast-fed infants of mothers with a B12 deficiency are at risk for severe developmental abnormalities and irreversible neurological damage. Some experts say that it’s the most common nutritional deficiency in the developing world and possibly in the United States as well.

...the crystalline form of the vitamin contained in pills and breakfast cereals is more readily absorbed than the “natural” form found in food... Plants neither use nor contain vitamin B12, so the only dietary sources are animal-derived: meat, fish, shellfish, poultry, eggs, milk, and milk products. Beef liver and several varieties of fish contain high amounts, dairy products and eggs not so much. Vegetarians can eat tempeh, which is made from fermented soybeans (the bacteria produce B12).

In normal digestion, stomach juices pry B12 loose from animal protein. But the small intestine can’t absorb the vitamin in this liberated, solo state. To be absorbed, it must be combined with a protein called intrinsic factor that is produced by cells in the lining of the stomach.

Four ways deficiencies develop
1. Diets without food derived from animals. (Explained above.)
2. Lack of stomach acid. Up to 30% of people ages 50 and over suffer from atrophic gastritis, a thinning of the stomach lining. This condition reduces the acid secretions that free B12 from animal protein, so much less is absorbed by the small intestine.
3. Lack of intrinsic factor. Some people’s stomachs don’t make enough intrinsic factor, so they can’t absorb enough B12.
4. Gastrointestinal disorders and surgeries. Crohn’s disease might cause a B12 shortage because it interferes with the functioning of the small intestine. Some people develop a B12 shortage after a surgical procedure that shrinks the stomach, such as gastric bypass, because a smaller stomach means far fewer of the cells secreting stomach acid and intrinsic factor.

I sure am glad I take my multi-vitamins!

Source: Harvard Health Letter, Volume 30, No. 10 - "Are You Getting Enough of This Vitamin?"

Aborption of Vitamins & Minerals

In my internet travels, I've come across the concept of "detoxification" - a process of cleaning out the digestive system so that your intestines can better absorb minerals. Usually websites promoting a colon cleanse product state something about how the FDA hasn't approved any such treatment. I came across an article on osteoporosis that mentions detoxifying as a preventative measure for bone disease.

Dirty colons or eating foods with hydrogenated oils that build up on the walls of the intestinal tract. These reduce the absorption of nutrients needed for bones... The older we become, the more important it is to detoxify; clean the colon for proper absorption and being able to assimilate the vitamins and minerals to make use of them.

I appreciate reading about preventative medicine - it seems rare in this society. We're always so concerned with fixing things after they happen that we completely ignore the root of the problem.

Besides that, the article talks about all the regular stuff we've learned in class so far - take your vitamins, eat healthy, and start as early in life as possible. It mentions B complex and B12 as one of the necessary vitamins, but that's all regarding the B group. Not that much info on the web regarding B6, B12 and bones :(

Article: http://allafrica.com/stories/200710220091.html

Vitamin B12 Helps Bone Health

Vitamin B12, found in dairy products, meats, poultry and fish as well as in many fortified cereals, may be an important weapon in your battle against osteoporosis. New research at Tufts' Jean Mayer USDA Human Nutrition Research Center on Aging (HNRCA) has uncovered a positive association between vitamin B12 and bone health.

The Tufts researchers measured bone mineral density-a gauge of bone quality--and vitamin B12 levels in more than 2,500 men and women participating in the Framingham Osteoporosis Study. They found that both men and women with low vitamin B12 levels also averaged lower bone mineral densities than those with higher levels. The men with low vitamin. B12 levels had significantly lower bone density in several areas of the hip, and the women low in B12 had particularly low bone density in the spine. Low bone density puts people at increased risk of the bone-weakening disease of osteoporesis.

"This is the first large-scale study of its kind to show an association between low vitamin B12 and low bone mineral density in men, and it confirms other reports of this association in women," says Katherine Tucker, PhD, director of the HHNRCA's Dietary Assessment an Epidemiology Research Program. "It shows that getting enough vitamin B12 from meats, poultry, fish and dairy products may be important for both men and women in maintaining strong bones."

Some individuals, particularly older people, have difficulty absorbing vitamin B12 from foods, however. So, Tucker adds, "inclusion of breakfast cereals fortified with vitamin B12 or use of vitamin B12 supplements offers additional protection."

Exactly how B12 is linked to bone density is unknown, as is the ultimate significance of B12 to bone health.*

According to a recent surgeon general's report, some 10 million Americans age 50 and older already have osteoporosis, with another 34 million at risk. As the population ages, those numbers are expected to grow by 2020 to 14 million plus 47 million more at risk-half of all Americans over 50.

"Osteoporosis is becoming a much greater issue now that people are living so much longer," says Tucker, who was the lead author of the study, published in the Journal of Bone and Mineral Research. "Our study provides support for a way in which people can actively lower their risk of osteoporosis and help to preserve quality of life."

The recommended daily value of vitamin B12 is 2.4 micrograms (mcg). Good food sources of vitamin B12 include:

• Dairy products (make sure to pick low-fat or fat-free); an eight-ounce container of low-fat vanilla yogurt, for example, contains 1.2 mcg of B12
• Meat (again, opt for lean cuts)
• Fish; four ounces of salmon contain 3.18 mcg of B12
• Poultry
• Eggs
• Fortified breakfast cereals; a fortified wheat-flake cereal such as Total contains 8.56 mcg of B12 in a one-cup serving

Because the body's ability to absorb B12 from food typically declines with age, older people may need to take vitamin B12 in a multivitamin/mineral supplement or in the high levels of fortified cereals. [1]

* I found another piece of information that discusses how Vitamin B12 works, which the previous article seemed to omit.

Vitamin B12 keeps your levels of homocysteine (an amino acid) from rising and weakening bones. [2]

Besides getting enough calcium and vitamin D, healthy bones also need B12. Tufts University scientists used special scanning equipment to measure bone-mineral density and blood levels of B12 in nearly 2,600 men and women. Among those with low B12 levels, women had less dense bones in the spine and men had less solid hip bones. Because B12 can be easier to absorb in concentrated form after age 50, the researchers recommend getting 100% of the DV for B12 (6 mcg) from either a fortified breakfast cereal or a multivitamin. [3]

Sources:
1. Tufts University Health & Nutrition Letter; Jun2005, Vol. 23 Issue 4, p1-2, 2p
2. Prevention; Aug2006, Vol. 58 Issue 8, p75-75, 1p, 2c
3. Prevention; Aug2005, Vol. 57 Issue 8, p79-79, 1/4p