How To Avoid Vitamin B12 Deficiency And What Foods To Take For This?

A vitamin, the deficiency of which is constantly frightened by adherents of plant nutrition, and by a complex formula - students in the first pair in biochemistry. The king among vitamins is Cobalamin or Cyanocobalamin - its more common form, which is heard in the light of fashion trends in a healthy lifestyle.

The biological role of vitamin B12 is enormous: its active forms (adenosylcobalamin and methylcobalamin) affect a number of important processes in the human body, being part of such enzymes as methionine synthase and Methyl-malonyl-CoAmutase:

1. Methionine synthase catalyzes the methylation reaction (in other words, the transfer of the CH3 group), which ensures the conversion of homocysteine, known for its negative effect on the endothelium of vascular capillaries, back into the amino acid methionine.

   Hyperhomocysteinemia is closely associated with atherosclerosis, however, more research is currently being conducted between the correlation of low serum cobalamin levels and atherosclerotic disease.

2. Methyl-malonyl-CoAmutase is responsible for the formation of succinic acid - one of the most important pieces on the chessboard of the Krebs cycle - that furnace that relentlessly provides raw materials for the production of energy by mitochondria.

   If the course of this reaction is disturbed (due to B12 deficiency), METHYLMALONIC ACID will accumulate - it is a toxic compound and is incorporated into phospholipids and the myelin sheath of the brain.

Consider other, clinically equally important functions of this vitamin:

1. It takes part in the formation of the myelin sheath of nerves - this is the same insulator that prevents nerve impulses from spreading, jumping from one fiber to another.

   The pathological process, accompanied by a violation of its formation, leads to motor disorders, paralysis, decreased sensitivity and speed of nerve impulses.

   That is why hypovitaminosis will be accompanied by damage to both the white and gray matter of the brain, and the development of cognitive disorders, degeneration of the spinal cord, polyneuropathy (multiple lesions of peripheral nerves).

   Study: Neurological disorders in vitamin B12 deficiency

   Due to demyelination, characteristic complaints in patients will be numbness of the hands and feet, memory impairment, goosebumps (paresthesia in the limbs).

2. Activates cell division.

   If this function is impaired (for example, in conditions of cobalamin deficiency or impaired absorption, which we will also analyze in this article), pernicious anemia develops - a disease accompanied by the growth of erythrocyte precursor cells without their further division. As a result, giant immature erythrocytes, megaloblasts, form in the red bone marrow.

   Note: Classic pernicious anemia occurs when autoimmune destruction of parietal cells (when antibodies attack their own stomach lining). As a result of this, there is a decrease in the secretion of the intrinsic factor of Castle (this will be discussed later).

   However, it should be noted that this disease is also associated with other autoimmune processes: in particular, in the thyroid gland, diabetes mellitus and vitiligo.

3. From methionine, obtained as a result of B12-dependent methionine synthase catalyzed, S-adenosylmethionine is formed - a universal donor of methyl groups necessary for:

   • Neutralization of histamine (an inflammatory mediator that increases the permeability of the vascular walls). It is he who is responsible for the development of pseudo-allergy, when the level of IgE, which rises with true allergic reactions, remains within laboratory references.

   • Synthesis of neurotransmitters: dopamine, serotonin, adrenaline.

   • Synthesis of nucleotide bases of DNA.

   • estrogen metabolism.

   • Neutralization of exo- and endotoxins.

   • Transformation of some heavy metals (arsenic, for example).

   • DNA methylation - to turn genes on and off.

4. B12 is responsible for maintaining blood pressure and reproductive function.

   B12 deficiency can also cause:

   • dizziness;

   • cheilitis (Fig. 1);

   • stomatitis (Fig. 2);

   • ulcers and erosion;

   • diarrhea;

   • seborrheic dermatitis;

   • noise in ears;

   • soreness of the tongue;

   • dementia with or without mood changes;

   • disorientation;

   • difficulty walking;

   • loss of appetite;

   • fatty liver;

   • violation of the menstrual cycle.

   Study: Hair, Nails, and Skin: Differentiating Cutaneous Manifestations of Micronutrient Deficiency

Behavior and vitamin B12 levels - what do they have in common?

In the work of Valentina Bonnefil, the relationship between the thickness of myelin and asocial, also characteristic of depression, behavior of experimental groups of mice was determined.

The study used lysolecithinase, which leads to the thinning of myelin, which led to social avoidance reactions in rodents. Three weeks later, when the fiber structure returned to normal, the behavior of mice ceased to differ from the control groups.

And for the synthesis of myelin, as already mentioned, it is vitamin B12 that is responsible.

Metabolism of vitamin B12

Around Cyanocobalamin, and in particular, the mechanisms of its synthesis and assimilation, there have always been a lot of rumors - let's finally dispel pseudoscientific and unsubstantiated fears and beliefs.

• Vitamin B12 is synthesized by some bacteria in the gastrointestinal tract of animals and then taken up by the host.

• Cyanocobalamin is concentrated in animal tissues, which is why it cannot enter the human body with food of plant origin.

• Dietary vitamin B12 is released under the action of hydrochloric acid and gastric enzymes and re-binds to the haptocorrin protein.

• In the alkaline environment of the duodenum, pancreatic proteases cleave haptocorrin, and cyanocobalamin already binds to the internal factor of Castle (this is a glycoprotein secreted by the parietal cells of the gastric mucosa). It is in this form that it will be absorbed in the small intestine - up to the ileum.

• A large amount of B12 accumulates in the liver - which is why often the clinical manifestations that accompany insufficient intake of this vitamin with food can appear after 5 or even 10 years (as in the case of most vegetarians).

• From 1 to 5% of cobalamin is absorbed independently of the internal factor of Castle (by passive diffusion).

• In the peripheral blood, cobalamin circulates only in a bound state with proteins - transcobalamin 1 or transcobalamin 2 - this has an important diagnostic value.

• The cobalamin-transcobalamin 2 complex is called holotranscobalamin - and it can be absorbed by different cells in our body, while vitamin B12, associated with transcobalamin 1, is absorbed only by the liver and kidneys.

The main risk groups for B12 deficiency

1. Patients with atrophic gastritis.

   This is a chronic disease, accompanied by damage to the gastric mucosa and, as a result, a decrease in the number of functioning cells. The secretion of hydrochloric acid and the production of intrinsic factor Castle is reduced, which negatively affects the absorption of vitamin B12. What's more, the resulting hypochlorhydria (reduced production of hydrochloric acid) leads to bacterial overgrowth - both in the stomach and in the small intestine (since it has powerful antimicrobial properties). The growing microflora competes for cyanocobalamin with the host organism, that is, a person, which further exacerbates its deficiency.

   H. pylori infection can also contribute to the development of atrophic gastritis, provided that they irradiate from the pyloric region to the fundus and body of the stomach.

   Symptoms of low acidity are:

   • Bloating.

   • Gas formation.

   • Digestive disorder.

   • Unformed stool.

2. Patients taking long-term proton pump inhibitor drugs (omeprazole and lansoprazole) and histamine H2 receptor antagonists (tagamet, zantac, pepsid), which also reduce the production of hydrochloric acid.

3. Metformin is associated with B12 deficiency, according to recent studies.

   Study: Vitamin B12 deficiency – A 21st century perspective

4. Hypothyroidism - a decrease in the functional activity of the thyroid gland also leads to a decrease in the absorption of cyanocobalamin.

5. Exocrine pancreatic insufficiency, accompanied by a decrease in the secretion of proteases: haptocorrin in this case will not be destroyed, and B12 will not be able to bind to the internal factor of the Castle.

6. Taking antiepileptic drugs (however, this issue requires more research).

   Study: Vitamin B12 in Health and Disease

7. Taking chloramphenicol (antibiotic), neomycin (antibiotic), colchicine (an alkaloid used in the treatment of gout, grapefruit is rich in it), cholestyramine (a cholesterol-lowering drug).

8. An equally important cause of deficiency is the lack of adequate amounts of animal products in the diet.

9. Invasion by cestodes - tapeworms (D.latum, together with other parasites, compete for B12).

    

10. Older age - The ability of the gastrointestinal tract to absorb vitamins and minerals as a whole decreases with age.

11. Crohn's disease is an autoimmune disease that causes inflammation of the colon and, as a result, reduced absorption of important nutrients.

12. Bariatric surgery - Patients undergoing such weight loss surgery often have problems absorbing vitamins, including cyanocobalamin.

    In addition, many scientific papers reflect the relationship between vitamin D and B12 deficiencies.

    Study: Correlation of Vitamin D3 (Calcitriol) Serum Concentrations with Vitamin B12 and Folic Acid in Women Undergoing in vitro Fertilization/Intracytoplasmic Sperm Injection

    It is noteworthy that nitric oxide (a powerful vasodilator), by inhibiting both B12-dependent enzymes (methylmalonide-CoA mutase and methionine synthase), thereby causes deficiency symptoms, despite the normal concentration of B12 in the blood serum.

    Study: Vitamin B12 in Health and Disease

B12 and thyroid

Cobalamin deficiency has been frequently reported in patients with autoimmune thyroid disease. This relationship seems to be associated with a violation of its absorption in patients with atrophic gastritis and / or pernicious anemia, which in 35-40% of cases accompany autoimmune processes in the thyroid gland.

The study reported that 1/3 of patients with primary hypothyroidism had antibodies against gastric parietal cells and against intrinsic factor of Castle.

Relationship between vitamin B12 deficiency and diabetes

Type 2 diabetes can rightly be considered a disease of the 21st century. The study involved 1007 people (58% women) with an average age of 66 years - all of them were ill for more than 10 years.

The results indicate a high prevalence of cyanocobalamin deficiency - and in elderly patients with a longer course, hypothyroidism and taking metformin, it was much higher and more common.

Vitamin B12 and neural tube defect

Neural tube defect includes non-closure of the vertebral arches (spinabifida), anencephaly (intrauterine malformation; complete or partial absence of the cerebral hemispheres, bones of the cranial vault and soft tissues), encephalocele (cranial hernia).

Vitamin B12, due to its role as a cofactor for the enzyme methionine synthase, plays a key role in the pathogenesis of development - or one of those: at its low concentration, folate, which is so necessary for DNA synthesis, cannot transfer a methyl group to cobalamin - and homocysteine ​​​​is not converted back to methionine . Cell replication is disrupted.

Vitamin B12 and osteoporosis

The development of osteoporosis has been linked to dietary factors such as inadequate intake of vitamin D, calcium, and protein. However, recent studies also show a direct relationship between elevated homocysteine ​​levels and the risk of bone fractures.

Vitamins B12, B6, B9 are necessary for the normal metabolism of this amino acid.

Reasons for increasing B12:

• Taking B12 drugs.

• Hepatitis, cirrhosis and other liver diseases.

• Intestinal dysbiosis.

• Malignant diseases of the hematopoietic system.

Diagnosis of vitamin B12 levels

1. Diagnosis of vitamin B12 is based on determining its level in the blood. REFERENCE: 189-833 pg/ml.

   OPTIMUM: from 600 and above.

   However, a significant number of patients with a subclinical course of the disease have normal values. That is why it is much more effective to identify earlier markers of deficiency:

   • methylmalonic acid in organic acids in urine ("gold standard");

   • homocysteine ​​in blood serum.

   Study: Vitamin B12 deficiency

   It should also be borne in mind that the concentration of methylmalonic acid can increase with renal failure - this is especially true for the elderly.

   Study: Vitamin B12 in Health and Disease

2. Newer research methods: Measurement of holotranscobalamin is a sensitive marker of B12 metabolism.

   REFERENCE: 25.1-165 pmol/l

3. In the GENERAL BLOOD ANALYSIS, a lack of cyanocobalamin is indicated by an increase (closer to the upper limit of the reference) in MCV - the average volume of erythrocytes.

4. TEST FOR PERNICIOUS ANEMIA: detection of autoantibodies to the intrinsic factor of Castle.

5. An increase in propionic acid in organic acids in the urine is observed with dysbiosis that occurs due to hypochlorhydria (a decrease in the production of hydrochloric acid).

   Propionic acid, like methylmalonic acid, is toxic and leads to demyelination of nerve fibers with all the ensuing, already mentioned consequences.

Foods High in Vitamin B12

• Vongole clams (84 mcg per 3 oz)

• Mussels (20.4 micrograms per ounce)

• Liver (26-58mcg/100g)

• Beef and lamb (1-3/100g)

• Eggs (1-2.5mcg/100g)

• Dairy products (0.3-2.4 mcg/100g)

• Trout (7.2 mcg)

• Keta (4 mcg)

• Sea bass (2 mcg)

• Cod (0.9 mcg).

Note: 1 US ounce = 28.349525 grams

RECOMMENDED DAILY DOSE:

• 0-6 MONTHS: 0.4 mcg

• 7-12 MONTHS: 0.5 mcg

• 1-3 YEARS: 0.9 mcg

• 4-8 YEARS: 1.2 mcg

• 9-13 YEARS: 1.8 mcg

• 14 YEARS AND OVER: 2.4 mcg

• PREGNANCY: 2.6 mcg

• BREASTFEEDING: 2.8 mcg

DAILY RATE B12: 6 mcg

What form of vitamin B12 to choose

The study involved lacto-vegetarians (who consume dairy products along with plant foods). For eight weeks, one part of them took capsules with cyanocobalamin, and the second - whey powder with hydroxycobalamin, another form of vitamin B12.

According to the results, the total level of B12 in plasma had higher values ​​in patients taking cyanocobalamin. However, the increases in transcobalamin were similar in both groups.

It is also believed that the form of hydroxycobalamin is preferable for smokers.

Regarding the intake of supplements containing B12, on our own, we recall a few important rules:

• Cobalamin competes with many B vitamins - which is why it is better to take it separately, and not in combination.

• If, according to the results of genetics, you have disorders - in other words, mutations - in the genes of the folate cycle (and with homocysteine ​​\u003e 7, the presence of polymorphisms is very large), it is recommended to take the ACTIVE form of the vitamin - METHYLCOBALAMIN.

   

• Adenosylcobalamin is indicated for COMT++ (COMT-catechol-O-methyltransferase) mutation.

   

Vegetarianism and vitamin B12 - are they a compatible couple?

Vegetarians compared with non-vegetarians have a lower body mass index, lower cholesterol and blood glucose values. According to statistics, the mortality rate from coronary heart disease among them is also lower.

However, cyanocobalamin deficiency can nullify all of the above benefits.

Plant-based nutrition requires an adequate intake of B12 in the form of dietary supplements, since only the use of animal products compensates for all the body's needs for this vitamin.

Some plant foods contain already added cobalamin, while others (such as mushrooms and algae) contain cobalamin analogues that are inactive in humans. So far, there are only two studies showing that several types of Japanese seaweed (nori) prevent B12 deficiency in vegans.

Bacteria-contaminated or fermented foods, such as tempeh and Thai fish sauce, have also been reported to contain B12, but it may have a low affinity for intrinsic factor kasla or be poorly absorbed.

Tablets or injections?

A lot of clinical studies have been conducted regarding the effectiveness of oral and intramuscular administration of cyanocobalamin. As a result, scientists came to the conclusion that taking peros vitamin B12 is equally effective with its parenteral administration.

It is noted that a dose of 500 mcg is able to normalize its level, while in case of malabsorption syndrome it is recommended to prescribe 1000-2000 mcg / day for a month, and then - 125-500 mcg / day.

With gastritis, erosion and other damage to the gastric mucosa, sublingual forms are no less effective.