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If you feel fatigued, and suspect B12 deficiency, then see your doctor immediately. Before diagnosing vitamin B12 deficiency or pernicious anemia, your doctor will run a vitamin B12 blood test for vitamin B12 levels in your blood, in addition to measuring your red blood cells and homocysteine levels. Here are ten tests still used today to diagnose vitamin B12 and pernicious anemia.
Vitamin B12 deficiency symptoms:
Vitamin B12 deficiency can be difficult to catch, because it masks itself as many other conditions. Sometimes, B12 deficiency occurs as a secondary side effect of a primary illness like fibromyalgia, Crohn’s disease, or celiac disease. Other times, vitamin B12 deficiency symptoms are overlooked because of underlying conditions such as depression or diabetes.
The most common symptoms of vitamin B12 deficiency and pernicious anemia are:
Constant fatigue that is not relieved by sleep and does not result from overexertion
Aggressive behavior that is unusual
Difficulty focusing or paying attention
Forgetting words on “tip of tongue”
Forgetting numerical codes like phone numbers or PINs
Painful tingling and numbness in extremities (hands, feet, arms, and legs)
“Pins and needles”
Painful tingling or burning sensation in tongue and mouth
10 Tests that diagnose vitamin B12 deficiency and pernicious anemia
1)Serum vitamin B12 level: First, your physician will request a vitamin B12 blood test to determine if your vitamin B12 blood (cobalamin) levels are indeed low. Usually, if test results are positive, then vitamin B12 supplementationbegins immediately.
The vitamin B12 blood screening is the most important test for diagnosing vitamin B12 deficiency, and if you respond well to vitamin B12 supplements, then further testing is not usually required.
However, if your doctor suspects pernicious anemia, then he might order one or more of the following additional tests:
2)Complete blood count (CBC): A blood test to screen the amount of red and white blood cells. With pernicious anemia, your red blood cells become engorged and misshapen, resulting in low distribution of red blood cells throughout your body.
3)Serum folate level: Many people who have vitamin B12 deficiency also are deficient in the B vitaminfolate.
4)Serum lactate dehydrogenase (LDH): Your doctor might order a blood test measuring LDH levels.
5) Reticulocyte count: This test looks for reticulocytes (slightly immature red blood cells).
6) Homocysteine test: High homocysteine levels in your blood may indicate vitamin B12 deficiency, folate deficiency, or vitamin B6 deficiency.
7) Gastrin level: a test measuring the amount of the hormone gastrin in your blood may help doctors diagnose the cause of vitamin B12 deficiency.
8) Methylmalonic acid (MMA) test- With vitamin B12 deficiency, methylmalonic acid levels go up. The MMA test provides more proof of the existence of vitamin B12 deficiency.
9) Intrinsic factor antibody test: Pernicious anemia is an autoimmune disorder in which sufferers are not able to product intrinsic factor, a necessary hormone for absorbing vitamin B12. Before diagnosing pernicious anemia, your doctor has to confirm the existence of an antibody in your system that inhibits intrinsic factor production, thereby causing vitamin B12 deficiency.
10) Bone marrow staining: Sometimes, your physician might require a bone marrow biopsy in order to determine other potential causes of pernicious anemia or general red blood cell disorders.
What about the Schilling test for vitamin B12 deficiency?
In the past, doctors have used the Schilling test to diagnose vitamin B12 deficiency. The Schilling test involves swallowing harmless, radioactive doses of vitamin B12 and tracking its progress in your body. However, because it involves fasting and the use of low-dose radiation, and because it may cause side effects like nausea, the Schilling test is rarely used.
Schilling test—a test in which a harmless amount of radiation is used to assess whether a vitamin B12 deficiency exists (rarely used)
Vitamin B12 supplementation
Once diagnosed with vitamin B12 deficiency, your doctor will likely prescribe vitamin B12 shots, beginning with 1000 mcg of vitamin B12 per week.
These B12 shots are only available upon prescription.
After the first month, B12 shots may be decreased to once per month, upon doctor’s orders.
If B12 deficiency symptoms (fatigue, muscular pain, and brain fog) continue despite vitamin B12 injections, you may supplement with additional over-the-counter (OTC) vitamin B12.
Once your vitamin B12 levels are normal, your doctor will likely stop vitamin B12 shots in favor of OTC vitamin B12.
Sublingual vitamin B12 are an OTC option that may require supplementation two or three times per day. Side effects may include unpleasant taste and burning, tingling sensation on the tongue.
Note: Sublingual vitamin B12 must be dissolved under the tongue as indicated; if they are chewed or swallowed, then vitamin B12 will not be absorbed.
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Read more about vitamin B12 deficiency and pernicious anemia:
The elderly need to increase their intake of vitamin B12, in order to avoid memory loss from vitamin B12 deficiency. Brain loss caused by Alzheimer’s disease and other forms of dementia is sometimes a part of the aging process, but by getting enough vitamin B12 in your blood, you can prevent suffering the symptoms of vitamin B12 deficiency.
Chicago study links low levels of vitamin B12 with memory loss
A 2011 study that focused on 121 community-dwelling participants of the Chicago Health and Aging Project found a strong correlation between vitamin B12 deficiency and memory loss. Scientists measured methylmalonate levels to determine vitamin B12 deficiency.
They found a direct relationship between low levels of vitamin B12, reduced brain volume, and decreased cognitive skills, such as loss of short-term memory.
Scientists noted poorer memory skills, slower thinking processes, and impaired comprehension skills as attributes associated with elevated methylmalonate levels- an indicator of vitamin B12 deficiency.
Also considered were plasma homocysteine levels, which scientists also connected with loss of brain mass. High levels of homocysteine are common in vitamin B12 deficiency.
Scientists concluded that methylmalonate, an indicator of vitamin B12 deficiency, has a direct impact on brain volume, and that vitamin B12 has multiple benefits on brain chemistry beyond just memory skills.
In 2008, a UK study conducted by the University of Oxford produced similar results; namely, that vitamin B12 deficiency is a likely cause of brain atrophy, dementia, and short-term memory loss among the elderly.
For the elderly, eating foods with vitamin B12 isn’t enough
Eating plenty of foods rich in vitamin B12 is always a good idea; such foods include protein sources like beef, chicken, fish, eggs, milk, and cheese. But for the elderly, the problem isn’t really eating enough sources of vitamin B12, but rather digesting them. Part of the aging process involves making less stomach acids that are necessary for absorbing vitamin B12 from foods. As a result, many elderly individuals who include meat in their diet still run a high risk for getting B12 deficiency.
Unless blood tests indicate healthy levels of vitamin B12, senior citizens must supplement with vitamin B-12 (cobalamin) with a routine prescribed B12 shot in order to avoid the symptoms of vitamin B12 deficiency.
Memory loss in B12 deficiency for the young and old
It isn’t just the elderly who should be concerned with memory loss- short-term memory loss is one of many symptoms of vitamin B12 deficiency, regardless of age.
Numerous studies linking elevated homocysteine with mental illness prove that symptoms of vitamin B12 deficiency caused by low B12 (cyanocobalamin) in the blood are often mistaken for mental health issues, such as depression, dementia, and schizophrenia.
What is homocysteine?
Homocysteine is an amino acid that your body makes when you eat meat products. Having too much homocysteine in your blood supply causes damage to your arteries and increases your risk for heart disease and stroke.
What is B12, and how does it regulate homocysteine?
Vitamin B12 is a nutrient that occurs exclusively in animal-based foods such as beef, chicken, fish, eggs, and milk products. Some of the riches sources of vitamin B12 are organ meats (liver, heart), oysters, and clams.
Together with vitamin B6 and folic acid, vitamin B12 helps break down homocysteine and keep them at a safe, healthy level. Without sufficient stores of these essential vitamins, homocysteine levels would escalate, leaving you at a high risk for developing diseases associated with elevated homocysteine levels, such as neurological impairments and cardiovascular disease.
Elevated homocysteine plasma levels are one of many symptoms of vitamin B12 deficiency.
What illnesses are associated with elevated plasma homocysteine levels?
Scientists believe that homocysteine is behind a wide variety of conditions and illnesses, from visual problems and eating disorders, to heart disease and schizophrenia.
Currently, most scientists agree that elevated homocysteine levels share a significant correlation with the following diseases:
Atherosclerosis (hardening and narrowing of the arteries)
Increased risk of heart attacks
Increased risk of strokes
How many studies link elevated plasma homocysteine levels with mental illness?
A growing number of scientific studies prove a significant correlation between vitamin B12 deficiency, homocysteine levels, and mental health problems, such as schizophrenia, depression, chronic fatigue, dementia, and even eating disorders in women.
1- In Beersheva, Israel, a study focused on treating patients of Alzheimer’s and cerebrovascular disease with folic acid, vitamin B6, and vitamin B12 supplements. In this randomized, double blind, placebo-controlled, crossover study, scientists of Ben Gurion University noted dramatic cognitive benefits in patients who received the vitamin supplements.
2- In Boston, Massachusetts, a Tufts University study linking low vitamin B12 and cognitive impairment in the elderly noted a direct correlation between vitamin B12 deficiency and anemia, macrocytosis, and cognitive problems such as dementia.
4- Elevated plasma levels of homocysteine in females with eating disorders were also the focus of this German study that linked excessive homocysteine with depression, anorexia nervosa and bulimia nervosa.
5- A Swedish study on older patients with mental illness concluded that age and plasma homocysteine levels more accurately predict cognitive functioning skills than brain imaging, as measured by the Mini mental state examination (MMSE).
Read more about vitamin B12 deficiency and mental illness:
Being tired all the time is a symptom of B12 deficiency, but it can also signal hypothyroidism (low thyroid), a thyroid disease that occurs with lowB12 levels. Because hypothyroid symptoms are similar, vitamin B12 deficiency often goes undetected.
B12 deficiency causes fatigue, depression, and other mood disorders often associated with an underactive thyroid. If you’ve been diagnosed with thyroiditis, then it’s also important also to recognize the symptoms of B12 deficiency, and know whether you might require more vitamin B12 (cobalamin).
What is hypothyroidism?
Hypothyroidism is an autoimmune thyroid disease (AITD) that occurs in the thyroid gland, causing inflammation, and reducing its ability to produce sufficient amounts of thyroid hormones. Hashimoto’s disease is one example of thyroiditis that causes low thyroid levels.
Sometimes, thyroid treatment for hyperthyroidism (overactive thyroid), such as radioactive iodine or surgery, can backfire, causing underactive thyroid symptoms.
Vitamin B12 is a water-soluble nutrient that is responsible for making red blood cells, controlling DNA synthesis, regulating the nervous system, and improving cognitive functioning. Without proper levels of vitamin B12, you may suffer neurological damage, dementia, or heart attack resulting from elevated homocysteine levels.
In a study conducted in Sapir Medical Center, Kfar Saba, Israel, patients with autoimmune thyroid disease received blood screening for vitamin B12 deficiency. Researchers noted a significantly high percentage of people with AITD who also had vitamin B12 deficiency caused by pernicious anemia, a disease that inhibits proper absorption of vitamin B12.
Another study conducted in Pakistan by Aga Khan University produced similar results; namely, a 40% prevalence of vitamin B12 deficiency among patients with hypothyroidism.
If you are a patient of hypothyroidism, then physicians strongly recommend routine blood testing for vitamin B12 deficiency, regardless of thyroid hormone levels.
Vitamin B12 deficiency can start with a few symptoms like tiredness and slight tingling or numbness in hands and feet; ignore the symptoms and low B12 levels could escalate into severe nerve damage, disease or death.
What are the symptoms of vitamin B12 deficiency?
Below is a list of some of the most common side effects which may arise from insufficient stores of vitamin B12.
(Please note that the severity of the symptoms may vary according to the stage of B12 deficiency.)
Vitamin B12 is a water-soluble nutrient. Therefore, your body is only able to store it for a short time. Vitamin B12 has many important functions in your body.
Vitamin B12 is essential for producing plenty of healthy red blood cells and for synthesizing DNA. A lack of B12 severely reduces your body’s ability to make sufficient red blood cells for carrying oxygen throughout your body.
Pernicious anemiais a life-threatening condition that is often the cause of vitamin B12 deficiency.
Your nervous system is dependent on vitamin B12, which enhances communication between the brain and your many nerve sensors, such as those in your fingertips, feet and mouth. This explains why sufferers of B12 deficiency notice a sensation similar to wearing gloves throughout the day; others report that their food tastes unusual, another clue that the body’s neurons are not operating correctly.
A deficiency of vitamin B12 compromises your nervous system and could result in permanent neurological damage.
Researchers have found a direct link between vitamin B12 deficiency and brain atrophy among the elderly. In one study which appeared in the Journal of Nutrition, senior citizens who had the highest levels of B12 experienced healthier cognitive functioning skills.
Vitamin B12 helps your body monitor already healthy homocysteine levels, a factor in heart health.
What diseases are associated with B12 deficiency?
There are many illnesses which occur when B12 levels are low; some conditions may be caused by vitamin B12 deficiency, while others are closely correlated. Below are some common illnesses associated with B12 deficiency, including many which most people don’t realize are affected by vitamin B12 levels.
Alzheimer’s disease, brain deterioration, cognitive decline, memory loss and other forms of dementia
Neurological diseases such as Multiple sclerosis (MS)
Cardiovascular disease, caused by high homocysteine levels
Mental illness, including depression, anxiety, bipolar disorder and psychosis
Autism spectrum disorder
Autoimmune diseases, such as AIDS and pernicious anemia
According to aTufts University study, 40 percent of people between the ages of 26 and 83 have low to medium-low B12 levels, indicating a deficiency severe enough to cause neurological disorder symptoms, while 9 percent are depleted enough to the point of irreversible neurological damage and life-threatening symptoms. Approximately 16 percent are close to becoming vitamin B12 deficient.
Why is vitamin B12 deficiency overlooked?
Only a blood test can properly determine if somebody is suffering from B12 deficiency, and most physicians don’t include a B12 screening with yearly check-ups. Also, many of the symptoms of vitamin B12 deficiency are similar to common health disorders, such as diabetes, chronic depression and fatigue.
How can you get enough B12?
Vitamin B12 is found in many high protein foods. Excellent sources of B12 are:
Lean beef cuts, such as chuck and sirloin
Fish, particularly salmon, tuna and halibut
Shellfish, including crab meat, mussels, clams and oysters
Dairy products, such as swiss cheese, yogurt, milk and cottage cheese
Vegans are at a high risk for developing vitamin B12 deficiency, as their diet specifically excludes food items which provide vitamin B12. Other people who are at risk of getting B12 deficiency are patients of weight loss surgery, diabetics on metformin, individuals with gastrointestinal disease, people who lackintrinsic factorand anybody taking prescription heartburn medication.
The only way to prevent becoming deficient in vitamin B12 is by constantly replenishing your body with B12-rich nutrients.
Alternatively, patients diagnosed with vitamin B12 deficiency are encouraged to take vitamin B12 supplements, such as sublingual B12 tablets, B12 shots, or over-the-counter (OTC) vitamin B12.
Find more information on preventing vitamin B12 deficiency:
Did your recent lab work point to vitamin B12 deficiency? A low vitamin B12blood test is serious. Symptoms of B12 deficiency can include nerve damage, loss of red blood cells, and mood disorders.
What is vitamin B12?
Vitamin B12 is a water-soluble nutrient which your body extracts from food sources such as lean meats, dairy products, eggs and fish. Vitamin B12 is necessary for producing plenty of red blood cells, maintaining a healthy nervous system, regulating homocysteine levels and monitoring DNA synthesis. A blood test which results in low B12 levels means that some of these vital bodily functions could be malfunctioning.
What causes low B12 levels?
There are many factors which can cause your B12 levels to dip dangerously low; these include:
Lack of intrinsic factor, a protein which is necessary for proper digestion of vitamin B12 from natural food sources
Long-term use of heartburn or antacid medication
Following a vegan diet, which excludes foods which are rich in vitamin B12, such as beef, chicken, milk, cheese, yogurt, eggs and fish.
Gastrointestinal conditions, such as Crohn’s disease or gluten intolerance
Weight loss surgery, such as gastric bypass surgery.
My lab test results indicate vitamin B12 deficiency. Should I be worried?
Due to the fact that it dissolves in water, your body is not able to hold vitamin B12 in the system for long; vitamin B12 must be constantly replenished through protein-rich foods or vitamin B12 supplements, in order to avoid becoming deficient in B12.
Regular lab blood testing is crucial for catching vitamin B12 deficiency before it has a chance to create any lasting impairment. If left untreated, vitamin B12 deficiency can lead to life-threatening illness and irreversible damage. These include:
Increased risk for heart attack, due to elevating levels of homocysteine
If you are not able to utilize sufficient stores of vitamin B12 naturally, then you must supplement regularly in order to avoid B12 deficiency.
For chronically low B12 levels, doctors have often administered vitamin B12 injections until symptoms abate.
Sublingual tablets are also often prescribed as a preventative measure, but recent studies indicate that under-the-tongue B12 supplements are not the most effective sources of B12, as they are not wholly digestible.
The Japanese study proves that women who eat foods enriched vitamin B12, vitamin B6, and folate are less likely to suffer heart attack or die of a stroke. Japanese men who eat B-rich foods are less likely to suffer heart failure.
These findings confirm similar studies which have been conducted in the US and Europe, all of which came to the same conclusion; B vitamins such as B12, B6 and folate are essential for cardiovascular health.
Through the Japan Collaborative Cohort (JACC) Study, a survey which collected data on the dietary habits of over 85,000 Japanese between the ages of 40 and 79, scientists were able to gain information on a correlation between the amount of B vitamin intake and likeliness of mortality from heart disease and stroke. Out of the 85,000 men and women studied, 986 died from stroke, 424 perished from heart attack and over 2,000 died from a variety of heart-related illnesses – all in a 14-year time frame.
Scientists grouped test subjects into five categories, varying in relation to B6, B12 and folate intake. Of the female test subjects who ate the lowest amounts of B6, B12 and folate, more were likely to die of stroke or heart attack than those who ate a moderate amount of B vitamins. Similarly, men who consumed the least B vitamins were more likely to die from cardiovascular illness than others. Of the test subjects who reported eating a steady diet of B6, B12 and folate, fewer suffered mortalities related to stroke or heart disease than counterparts from any of the other groups.
Scientists believe that B vitamins lower homocysteine levels, an amino acid which many doctors believe increase one’s risk of suffering from heart disease and stroke. Vitamins B6, B12 and folic acid prevent the accumulation of homocysteine. Eating whole grains, leafy vegetables, legumes and fish are excellent ways to get B vitamins. However, many suffer from an inability to completely digest B12, resulting in B12 deficiency. Symptoms include fatigue, memory loss and numbness or tingling in the extremities.
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.
Until recently, it has been difficult to test for vitamin B12 deficiency. An inability to properly absorb vitamin B-12 causes pernicious anemia and leads to fatigue and neurological problems. Physicians lacked a safe and simple way to test their patients for poor vitamin B12 absorption. In humans, only two enzymatic reactions are dependent on vitamin B12. In the first reaction, methylmalonic acid is converted to succinyl-CoA by using vitamin B12 as a cofactor. Vitamin B12 deficiency can lead to increased levels of serum methylmalonic acid. Homocysteine is converted to methionine by using vitamin B12 and folic acid as cofactors. A deficiency of vitamin B12 or folic acid may lead to increased homocysteine levels. An understanding of the vitamin B12 absorption cycle helps clarify the potential causes of deficiency. The acidic environment of the stomach helps to breakdown the vitamin B12 that is bound to food. The intrinsic factor that is released by parietal cells in the stomach binds to vitamin B12 in the duodenum.
Extensive research has resulted in a more accurate and safer test for vitamin B12 deficiency.The new test involves drinking a small amount of vitamin B12 labeled with radioactive carbon 14, and then extracting a drop of blood. The amount of carbon 14 labeled vitamin B12 in the blood sample is measured with an accelerator mass spectrometer that can count single atoms of carbon 14. The radiation dose involved is equivalent to that received on a cross-country flight.