Although food sources of B12 are considerably many and varied, most happen to be (if not all true sources) proteins, which means animal products. This is why so many vegans and vegetarians are at risk for a B12 deficiency. However, those items high in B12 are also fairly well known for their ability to add toxicity to the body. The RDA does not recommend much red meat or seafood high in mercury as part of the daily diet, but these are the items which possess the highest B12 values.

For example the items which are highest in the amount of B12 would be canned mollusks and clams in liquid – averaging 500 mcg of B12 (They average around 134 mcg of B12 if in a raw, unprocessed state). These widely popular foods are often extremely high in mercury and can actually be detrimental to your health if you eat too many.

Same sort of problems occur with meat. The meats highest in B12 would be lamb, beef and moose variety meats, by-products and internal organs such as kidneys, liver and even the brain (cooked and uncooked). These items average between 130 mcg to 85 mcg of B12 per type of protein. Most of these meat items however are too high in toxins to be consumed on a daily basis. In fact eating too many of these items too often will result in the individual developing a case of gout – arthritis like stiffening of the joints caused by the buildup of too many uric acid crystals.

Surprisingly however there are items which are both high in B12 and are safer to eat on a regular basis. Certain Alaskan fish such as whitefish and eggs each contain around 108 mcg of B12, while also providing omega-3s, healthy cholesterol and even choline. These are the sorts of items which may replace the unhealthier version of protein in your diet while delivering optimum dosages of the vitamin.

Ocean fish brings much less B12 – averaging around 2 mcgs of the vitamins. This is about the same as most cheeses, lean young fresh ground meat, crustaceans, and whey. The best option for a B12 rich diet is to consume plenty of dairy, egg and healthy fish sources very often, while enjoying the hotdog, the burger, the liver spread, ocean fish and mollusks should be left for a treat to keep your system healthy and strong.

Vitamin B12 is an essential vitamin for healthy brain function. It is important in helping to manufacture the myelin sheath which acts as a protective layer surrounding nerves in the brain and allows for extremely quick transmission of neural messages. It helps the brain to produce neurotransmitters, which are vital for communication within the brain. Some research has noted that among the many possible causes behind autism a thin myelin is a common symptom. Some believe that autism can be caused or symptoms worsened by severe nutritional deficiencies. What this means is that the body is not receiving enough of certain vitamins, or that it is not able to absorb the nutrients that are fed through the system; causing the body to lack the essential elements it needs to function properly. Recent research shows that more than 50% of children with autism have GI symptoms, food allergies, and maldigestion or malabsorption issues.

Altered intestinal permeability was found in 43% of autistic patients, but not found in any of the healthy control subjects. Intestinal permeability, commonly referred to as the “leaky gut”, means that there are significantly large spaces present between the cells of the gut wall. When these large spaces exist in the small intestine, it allows undigested food and other toxins to enter the blood stream. When incompletely broken down foods enter the body, the immune system mounts an attack against the “foreigner” resulting in food allergies, inflammation and sensitivities. This constant aggravated inflammation is an incredible uncomfortable experience for the individual.

This process also halts the absorption and utilization of vitamins and minerals, resulting in deficiency and its subsequent consequences. The deficiency further aggravates the well being of the autistic individual, and causes a sleuth of unpleasant symptoms. The food particles which pass through the wall cause the release of antibodies which trigger inflammatory reactions when the foods are eaten again. The chronic inflammation lowers IgA levels, which are needed to protect the intestinal tract from bacteria and yeast. The decreasing IgA levels allow for even further microbe proliferation in the intestinal tract. Vitamin and mineral deficiencies are also found due to the leaky gut problem.

An example of the problems created by the vitamin deficiencies that occur within a leaky gut is vitamin B12 deficiency. B12 absorption is inhibited early in this process as microbes enter the small intestine because B12 is absorbed in the ileum (last section of the small intestine). Another important function of B12 is repairing damaged, flattened microvilli. With sufficient B12 and folic acid in the bloodstream, the intestinal cells and microvilli can rejuvenate every 3-4 days.

In a healthy intestinal tract the small intestine and stomach are not inhabited by bacteria. When the flora balance in the colon is lost, the microbes can migrate into the small intestine and stomach, which hampers digestion. The microbes compete for nutrients and their waste products overrun the intestinal tract. One of the toxins produced by yeast is actually an enzyme that allows the yeast to bore into the intestinal wall. The yeast also produce other toxins such as organic acids, which can also damage the intestinal wall.

In the case of malabsorption, undigested carbohydrates left over in the small intestine cause the body to draw water into the intestinal tract. This pushes the undigested carbohydrates into the colon where the microbes can feast on it, and allows for even more proliferation of the unwanted microbes and continued increase in malabsorption problems. Low intestinal carbohydrate digestive enzyme activity was found in 43% of patients with autism. Recent studies point out that ongoing carbohydrate malabsorption keeps the digestive system constantly weakened, leading to systemic disorders. The vicious cycle of malabsorption, inflammation and food allergies seen in children with autism can be broken with B12 supplementation, beginning a cycle of healthy digestion which assists with the child’s overall well being.

Obviously the use of oral b12 supplementation is out of the question as it would not absorb and assimilate in the body. Injections are an extremely viable option but not when the patient has extreme sensitivity to touch, as is common in autism. A discreetly placed transdermal B12 patch may be the best choice for a means of supplementation as it remains unseen and bothersome all the whole helping to retune the system.

Vitamin B12’s position in the upkeep of one’s health is central. Among many of the aspects of health-maintenance B12 helps to control, minimize and flush the levels of an extremely toxic by-product of hormonal metabolism named homocysteine. Recent research has uncovered that a dangerous condition of elevated homocysteine levels can result from even minor B12 depletion. Individuals most at risk for having elevated levels of homocysteine are those who are most in need of vitamin B12 supplementation – vegetarians, individuals nearing middle-age, individuals suffering from poor absorption and unhealthy lifestyles. For all these groups, homocysteine levels soar and remain undisturbed as the body is unable to control and lessen its amounts.

Homocysteine appears to be a nerve and vessel toxin, promoting mortality, cardiovascular disease (CVD), stroke, Alzheimer’s Disease, birth defects, recurrent pregnancy loss, neural tube defects, eye disorders, increased fractures in elderly persons and nerve damage. Cardiovascular disease (CVD) includes Ischemic heart disease (IHD/heart attack), coronary artery disease (CAD/ plaque obstruction of the coronary arteries to the heart), and stroke. An elevated level of blood serum homocysteine is a powerful risk factor for all these issues

Homocysteine auto-oxidizes and reacts with reactive oxygen intermediates and damage endothelial cells (which are extremely important for protection of the blood vessel) and result in a higher risk of forming a thrombus (blood clot). Although homocysteine does not affect bone density, it appears to affects collagen by interfering with the cross-linking between the collagen fibers and the tissues they reinforce. The damage inflicted on these connective tissues results in increased cases of fracture, bone damage and importantly atherosclerosis which is specifically linked to high homocysteine levels.

Diseases which are associated with elevated homocysteine levels are long-term emergent problems. In other words these illnesses occur due prolonged exposure to elevated homocysteine which damages the tissues through its toxicity. In fact, elevated homocysteine levels are a part of aging, whether due to poor absorption in the GI or other reasons. As people are now living longer, the elevated homocysteine has more time to do its damage to the body, thus a spike is noted in illnesses associated with homocysteine levels and aging. Logically everyone should eventually attempt to control their homocysteine levels through B12 supplementation if they wish to lessen the risk of these illnesses

How is homocysteine produced in the body?
Methionine is an essential amino acid involved in hormonal metabolism which is obtained exclusively from ingested protein. In the processes of hormonal metabolism some methionine is turned into homocysteine. The body converts much of the homocysteine back into methionine through an intricate process involving the vitamin B12. If the individual is B12-deficient, homocysteine levels will begin to increase as the reaction of the compounds cannot take place. There are several studies discussing the benefits of B12 supplementation on homocysteine levels and health, and following are several excerpts from these studies.

Medically established normal serum levels of homocysteine range from 2.2 to 13.2 µmol/l. The levels of homocysteine in a typical Western population are around 12 µmol/l. Although this is considered to be within the “normal” range, it is not necessarily healthy.

The analysis of the Oxford Vegetarian Study reported in 2002 showed that overall mortality was the same between vegetarians and non-vegetarians. But vegetarians had 2.2 times the death rate from mental and neurological diseases as non-vegetarians.

The vegetarians had higher homocysteine and lower B12 levels leading to more neurological damage and problems.

Appleby PN, Key TJ, Thorogood M, Burr ML, Mann J. Mortality in British vegetarians. Public Health Nutr. 2002 Feb;5(1):29-36.

11 prospective studies of IHD and 8 of stroke tried to examine and anaylize the effects on health if homocysteine levels were lowered by 25%. The studies involved 9,025 people.

• A 25% lower homocysteine level reduced the risk of IHD by 11%, and the risk of stroke by 19%.
• In 16 prospective studies of IHD, a 5 µmol/l increase in homocysteine increased the risk of contracting IHD by 23%.
• In 8 prospective studies on strokes, a 5 µmol/l increase in homocysteine increased risk of a stroke by 42%.

Homocysteine is better controlled through adequate level of B12, B6 and folate (also known as folic acid). Since vegetarian diets are typically high in folate, the elevated homocysteine levels are normally due to a low B12 intake which, as studies have shown, cannot be viably obtained from ingestion of plant-life. The greater effect of elevated homocysteine on stroke compared to heart disease could explain why vegetarians have not been shown to have lower rates of death from stroke, while they do have lower rates of death from heart disease.

The British Medical Journal published an analysis of 12 studies on the effectiveness of reducing homocysteine levels with folic acid and vitamin B12. They concluded that folic acid in the range of 500-5,000 µg/day reduced homocysteine by 25%, and that B12 supplements (average intake of 500 µg/day) reduced it a further 7%. An addition of B6 did not show any further homocysteine level reduction.

    Vitamin B12 (Cobalamin) is the largest B vitamin, it is a red crystalline substance, necessary in reconstruction of DNA, and maintenance of healthy red blood and  neural cells. Just as mercury may cause B12 deficiency in the nervous system, so alcohol can cause deficiency in the tissues of the liver and the intestine. Unlike social drinking which often results in a spike of appetite, habitual alcohol consumption heavily and repetitively depresses the system, causing a general lack of hunger and increased nausea. Often in this diet alcohol replaces food, resulting in numerous deficiencies caused by the lack of an adequate intake of nutrients. Nutritional deficiencies are common among alcoholics, but they can also be found in people who just consume alcohol on a regular basis.

     Excessive alcohol consumption may damage the GI tract absorption in such a manner that the body is effectively experiencing starvation from the lack of nutrient assimilation into the system. It heavily impairs the body’s ability to break down and absorb the vitamin compounds in the stomach and intestinal lining. Alcohol also seems to raise serum levels of vitamin B12, so that the deficiency is masked and the subject may look like they have higher than normal B12 levels. In case of severe damage of the GI linings and impaired B12 metabolism supplementation of the vitamin will have to begin, and oral administration is not an option in this case. One will have to discuss the viability of b12 injections or the transdermal B12 Patch with his/her health practitioner.  

Alcohol’s effects of the stomach

Even moderate drinking can still cause changes in gastric acid secretion, cause acute gastric mucosal injury, and also interfere with gastric and intestinal motility.

Pernicious anemia, the autoimmune disease in which the body’s own white blood cells are directed against the intrinsic factor or the mucous stomach cells can be caused by an excessive alcohol consumption. It can also be aggravated by moderate to low alcohol consumption. Pernicious anemia causes a severe B12 deficiency, as the intrinsic factor is necessary for the absorption of the vitamin compound into the system.

Alcohol’s effect on Gastric Acid Secretion?

Alcohol consumption affects gastric acid secretion. In low to moderate doses it stimulates gastric acid secretion—in higher doses it causes inhibition.

Chronic alcohol consumption causes shrinkage of gastric mucosa and decreased gastric secretory capacity. This means the stomach is less able to kill bacteria that enter the body, which may lead to the colonization of the upper small intestine with potentially harmful organisms. These bacteria begin to devour all available nutrients which enter the body, often causing severe malabsorption of a number of vitamin and mineral substances

Even a single episode of heavy drinking can induce mucosal inflammation and hemorrhagic lesions. An inflamed GI lining is heavily impaired in terms of absorption capacity which may lead to severe vitamin and mineral deficiencies.

Alcohol causes damage to the muscle layers of the stomach wall and decreased GI smooth muscle contraction which mix incoming food with gastric fluids.

After chronic use of alcohol an increase in propulsive contractions occurs. These contractions cause diarrhea. The nutrients from the food ingested are not properly absorbed, and over a period of time this acts effectively as starvation, draining the body of all necessary nutrients and minerals. Increased hydration during periods of gastric distress further dilute and flush the vitamin and mineral reserves in the system.

Alcohol’s effect on the small intestine

The small intestine is the area where most nutrients are absorbed. Alcohol causes interference with absorption of nutrients and can cause interference with the enzymes needed for digestion, the transportation of nutrients to the bloodstream and the effectiveness of enzymatic metabolism.

Alcohol can cause mucosal damage even in healthy people during a single drinking episode which can lead to erosion and bleeding. Alcohol also causes an increase in intestinal permeability which lets large molecules that normally would not be able to cross the intestinal wall to get through. .

Diseases of the oral cavity and esophagus related to high alcohol consumption

Barrett’s esophagus: The lining of esophagus is replaced by abnormal cells which leads to abnormal acid production. This is a precancerous condition.

Gastroesophageal reflux disease (GERD): The sphincter weakens or relaxes, and the contents of the stomach splash back up into the esophagus.

Esophageal stricture: Cells lining the esophagus are damaged and cause narrowing of the opening. A person with this condition will have trouble swallowing foods.

Gastritis: The inflammation of the lining of the stomach.

Studies have shown that both moderate and heavy alcohol consumption will affect vitamin B12 levels. One study showed a 5% decrease in mean serum vitamin B12 concentrations when consumption of alcohol increased from 0 to 30 grams of alcohol/day.

Consumption of alcohol has been positively associated with breast cancer risk in epidemiological studies, but the mechanism by which alcohol might increase risk for breast cancer is not known. One possibility is that alcohol changes the metabolism of folate and B12, and this affects DNA stability and synthesis.

Researchers investigated the effects of moderate consumption of alcohol (1 or 2 drinks each day) in 53 postmenopausal, healthy, well-nourished women. There was a 5% decrease in the amount of serum vitamin B12 concentrations from 0 to 1 drink/d treatment. Alcohol intake had no significant effects on serum folate concentration. Among healthy, well-nourished, postmenopausal women, moderate alcohol intake may diminish vitamin B12 status.

Source: Laufer EM, HartmanTJ, Baer DJ, Gunter EW, Dorgan JF, Campbell WS, Clevidence BA, Brown ED, Albanes D, Judd JT, 2004. The Effects Of Moderate Alcohol Consumption Of Folate And Vitamin B12 Status In Postmenopausal Women. European Journal Of Clinical Nutrition.

Currently a new hype is taking over the nutrition community, and it is all about whether B12 supplementation can help you lose weight. Some companies are already focusing on bringing B12 rich dietary formulas to their consumers, but can this vitamin truly help you lose weight? And if so, how would it work.

Healthy B12 levels are necessary for the proper functioning of the body, as has been previously discussed. It is absolutely necessary in the formation of new tissues and protecting the DNA, but it also may have some influence on one’s overall metabolism rates. Especially if the individual is experiencing general issues with absorption in the stomach, as is common with B12 deficiency.

Lack of all the needed vitamins and minerals will cause the system to slow down when it comes to metabolism. This is the body’s way of assuring its own survival, as the malabsorption of nutrients is interpreted by the system as starvation (which by most definitions is accurate), and while slowing down the living processes may make one feel ill, it does keep the body from extreme further damage.

Once properly supplemented though this vital nutrient allows the body to operate more effectively and efficiently, which in the long run results in weight loss and improvement of overall health. Vitamin B12 is also an energy booster, and in properly administered amounts it results in the body having healthy, long-lasting energy.  This of course will not take off the pounds by itself, but the extra energy stores replacing the feeling of fatigue is often a great motivator to get up and move, resulting in weight loss.

The B12 patch is an excellent energy/metabolism booster. As it bypasses the GI tract there is no issues with absorption and bodily distribution. The patch begins to work within the first 15 minutes and the effects last to up to a week. Comfortable, discreet and convenient, it is extremely effective if one wishes to ban fatigue and feel renewed with energy.

Individuals with compromised absorption in their GI tract face a series of issues concerning their quality of life. As has been discussed before, impaired absorption in the stomach and the intestines results in vitamin and mineral deficiencies, which compromises one’s health and often causes existing medical conditions to worsen. Many individuals suffer with a number of symptoms of mineral/vitamin deficiency, starting from minor aches and pains, leading to affected mood in the form of depression and anxiety, and even to damage of neural and organ tissues. More so, research seems to indicate that individuals with impaired absorption are more likely to be overweight.

A number of causes may lay behind the extra weight carried by individuals with a compromised system of absorption. The most likely explanation is that the body tries to compensate for the lacking nutrients by increasing the feeling of hunger and forcing the individual to self-medicate using food. The absorption is not increased by the extra calorie intake however, and the waste products may begin to compact in the intestines causing further weight gain, bloating, absorption issues and general physical malaise.  

Although supplementation may still be necessary for these individuals, there is hope to dealing with the unruly digestive system. A change of dietary habits and specific intake of certain foods may not only increase your metabolism and general well being, but as well boost the absorption throughout the GI tract. Try adding a number of the following items to your dietary schedule for better mineral/vitamin intake and a health boost for your system.

Vitamin C – Add this in fresh form, using citrus fruits and other C rich foods. Vitamin C helps increase the absorption of Chromium, Zinc and Iron. Other foods that contain Vitamin C: Red and Green Peppers, Tomatoes and Broccoli.

Ginger – adding ginger to your diet can help digestive movement through the stomach and the stimulation of digestive enzymes.

Mint –mint aids digestion by stimulating the flow of bile to the stomach as well as calming the muscles of the digestive system.

Avoid drinking tea with your meal – although tea has many health benefits, it shouldn’t be imbibed with meals. Tea contains caffeine and can interfere with iron absorption. This is particularly bad for women who tend to have lower levels of iron. Avoid drinking tea for an hour either side of a meal.

 Some other foods that aid digestion – pineapple (contains Bromelain), papaya (contains Papain), figs, licorice and bean sprouts all aid digestion and help the absorption of needed nutrients.

The B12 vitamin has an extremely intricate relationship with the body’s chemical balances and thus its healthy function. There are a number of ways in which it protects and supports a variety of chemical interactions necessary for a normal quality of living and even survival. This short guide will introduce you to the basics of B12 chemical functions.

1) Vitamin B12 Regenerates Folic Acid

Without B12, folic acid (B9) becomes trapped in the body in a metabolically useless form. Folic acid is a necessary component in cell division and formation of new cells.

2) Healthy Red Blood Cells Depend on Vitamin B12 Driven Synthesis of DNA. Without usable B12 in the system, the DNA synthesis begins to shut down, resulting in pernicious/megaloblastic anemia. Symptoms of this illness include fatigue, Low energy levels, nausea and diarrhea, decreased appetite, weakening of the muscles, headaches, tingling sensations and a sore tongue.

3) Vitamin B12 Supports Synthesis of the Amino Acid Methionine and Amino Acid “SAM-e”

Methionine is one of the two sulfur based compounds involved in metabolic functions. It is a crucial building block of proteins necessary for a state of a healthy body. SAM-e is involved in over 100 enzymatic reactions required for normal metabolic activity.

5) Vitamin B12 Promotes Activity of Hormones and Neurotransmitters Affecting Your Mood

The hormones include dopamine, serotonin and melatonin. These particular neurotransmitters are necessary for a healthy balanced mood, emotional state and even the sleeping cycle. An imbalance in either the levels or the function of any of these can result in a depression which is likely to need medicating.

6) Vitamin B12 Helps Reduce Dangerous Levels of Homocysteine Homocysteine is a toxic amino acid (protein) associated with a number of different negative side effects in the body. High homocysteine levels can cause any of the following symptoms: tinnitus, anxiety, increased heart beat, worsening symptoms of thyroid disorders, depression and body toxicity. Individuals with high homocysteine levels are at risk for cardiovascular problems.

7) Vitamin B12 Benefits Help Prevent Irreversible Neurological Impairment Peripheral and central nervous system deterioration can occur due to a vitamin B12 deficiency. Vitamin B12 deficiency has been linked to demyelination of the nerve and the onset of Alzheimer’s disease and dementia.

Vitamin B12’s primary functions are in the formation of red blood cells, DNA synthesis and the maintenance of the nervous system. If B12 deficiency occurs, DNA production is disrupted and abnormal cells called megaloblasts manifest, which results in anemia. B12 protect the nerves which are surrounded by an insulating fatty sheath called the myelin. B12 plays a vital role in the metabolism of fatty acids essential for the maintenance of myelin. Prolonged B12 deficiency can lead to nerve degeneration and irreversible neurological damage. When deficiency occurs, it is more commonly linked to a failure to effectively absorb B12 from the intestine rather than the lack of B12-rich foods.

Vitamin B12 can be stored in small amounts by the body. Total body store is 2-5mg in adults. Around 80% of this is stored in the liver. Vitamin B12 is excreted in the bile and is then effectively reabsorbed - this is known as enterohepatic circulation. People on diets low in B12 may be obtaining more B12 from re-absorption than from the food they ingest. Re-absorption of the B12 from the bile is the reason it can take over 20 years for deficiency disease to develop. In comparison, if B12 deficiency is due to a failure in the absorption mechanisms it can take only 3 years for deficiency disease to occur.

The only reliable dietary sources of vitamin B12 are meat, dairy and eggs. The considerable research into possible plant food sources of B12 turned up few positive results. Fermented soya products, seaweeds and algae have all been proposed as possible sources of B12 because they are products which have been “pre-digested” into various amino acids, making them easier to absorb. However, analysis of fermented soya products, including tempeh, miso, shoyu and tamari, found no significant B12.

Spirulina, algae available as a dietary supplement in tablet form, and nori, a seaweed, have both appeared to contain significant amounts of B12 after analysis. However, it is thought that this is due to the presence of compounds structurally similar to B12, known as B12 analogues. These cannot be used satisfy dietary needs. The body is unable to differentiate between B12 and its analogues. Researchers have suggested that supposed B12 supplements such as spirulina may in fact increase the risk of B12 deficiency disease, as the B12 analogues can compete with B12 and inhibit metabolism. The current nutritional consensus is that no plant foods can be relied on as a safe source of vitamin B12.

Bacteria present in the large intestine are able to synthesize B12. In the past, it has been thought that the B12 produced by these colonic bacteria could be absorbed and utilized. However, the bacteria produce B12 too far down in the intestine, and as B12 is not absorbed through the colon lining, this B12 just gets flushed out of the system. Supplementations such as the injections or patch should be used if you begin to experience the symptoms of B12 deficiency and you know that you are at risk.

Research is showing that many older people could benefit from getting more vitamin B12 than they currently do. Some 10% to 15% of people over age 60 are outright deficient, and many more are borderline deficient. Their blood levels of B12 are in what’s called a “low-normal” range, and if their doctor isn’t up on the latest research, they won’t be treated for B12 deficiency with supplemental B12. That’s a shame, because research now shows that low B12 can cause all sorts of problems, and that getting an optimal amount can boost brain power, deter depression, improve bone density, reduce cancer risk and halt hearing loss and eye disease.

Here’s what the latest research shows vitamin B12 does:

Stops brain shrinkage. One study found that older people with lower-than-average B12 levels were six times more likely to show signs of brain shrinkage, an early sign of impaired cognitive function and Alzheimer’s disease. Even B12 levels that are above the traditional cutoff for deficiency — and seemingly adequate — may impair cognition in older people. B12 is needed to maintain the fatty myelin sheath that wraps around and protects nerves, including nerve cells in the brain.

Protects your eyes. Harvard researchers found at least a 34% decreased risk of age-related macular degeneration for women aged 40 and older who supplemented with 1,000 micrograms of B12. They attribute it to lower levels of the amino acid homocysteine and better antioxidant effects. Both improved blood vessel function in the retina of the eye.

Keeps your hearing sharp. There may be a connection between B12 deficiency and hearing. One study found that low blood levels of vitamin B12 were linked to a higher risk of hearing loss in women in their 60s. Toxic homocysteine may damage the delicate cells that transmit sound waves in the inner ear.

Fights depression. A study from the National Institute of Aging found women with low B12 levels were more than twice as likely to develop depression as women with normal B12 status. B12 is needed for the production of important brain neurotransmitters such as serotonin, norepinephrine and melatonin, the “sleep” hormone.

Maintains strong bones. In the Framingham Offspring Osteoporosis Study, people with low B12 levels had lower-than-average bone mineral density. B12 may build stronger bones by aiding osteoblasts, the cells that build bone, and by lowering homocysteine, which weakens bone by interfering with collagen cross-linking, the molecular “stitching” that makes bones strong and flexible.

Sidetracks cancer. Harvard researchers found that women over age 65 who were supplementing with B vitamins (including 1,000 mcg of B12) were 25% less likely to develop invasive cancer of any kind and 38% less likely to develop breast cancer in particular. B12 may help prevent or repair the genetic damage that can cause cancer.

Older people often don’t absorb enough B12, even when they get enough in their diet. Some experts believe that blood B12 levels should be at least 350 picomoles/liter (or 44 picograms/mL.) It’s a good idea to have your blood level checked if you are over age 50. Symptoms of B12 deficiency include fatigue, depression, numbness and tingling of the arms and, most commonly, the legs, difficulty walking, memory loss, disorientation, tongue soreness, and appetite loss. Because so many older people are borderline deficient, more experts are recommending anyone age 50 or older get at least 100 to 400 mcg a day of B12.

Your risk for deficiency increases as you get older, and the consequences for your health can be devastating. Taking a B12 supplement is good insurance against deficiency, and B12 supplements are also very well tolerated. It’s a good idea to ask your doctor to check your B12 levels to determine whether you may have a severe deficiency that warrants much higher levels of supplementation.

Intrinsic factor is a protein produced by the cells of the stomach, parietal cells, which also produce the acid (gastric juice) for digestion. The intrinsic factor is the compound which facilitates and allows the absorption of vitamin B12 from food in the stomach and the intestines.

Once ingested the B12 becomes bound to a binding proteins present in the hydrochloric acid of the stomach. In the less acidic environment of the small intestine, these proteins separate from the vitamin, enabling it to bind to intrinsic factor and enter the bloodstream.

 The intrinsic factor is an enzyme-like unidentified substance secreted by the stomach. It is present in the gastric juice as well as in the gastric mucous membrane. The optimum pH for the action of the intrinsic factor is 7 and it is inactivated at temperatures above 45^oC.

In pernicious anemia, an autoimmune disease, autoantibodies direct themselves against the intrinsic factor and/or parietal cells themselves and lead to an intrinsic factor deficiency, which results in malabsorption of vitamin B12. Atrophic gastritis, an inflammation of the mucous membrane of the stomach, can also cause intrinsic factor deficiency and anemia through damage to the parietal cells. Pancreatic exocrine insufficiency can interfere with normal dissociation of vitamin B12 from the proteins, as well preventing its absorption via the intrinsic factor structure. Bariatric surgery is a known risk factor in the development of pernicious anemia, other risk factors include stomach tumors, gastric ulcers, and excessive consumption of alcohol.

Patients experiencing an insufficiency in their intrinsic factor levels cannot benefit from a low dose oral vitamin B-12 supplement, because it will not absorb through the wall of the small intestine. Historically, the disease was thought untreatable before the discovery that it could be managed with regular injections of vitamin B-12, thus bypassing the digestive tract. Other options are available nowadays if injections are not the desired method of supplementation.