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B-Complex with Metafolin B-Complex with Metafolin 60 caps.
32.36 $

B-Complex with Metafolin 60 caps.

From 3 units only 31.72 $ /Units.

As an alternative, we recommend:

B-Balance  120 caps.
B-Balance 120 caps.
Apollo's Hegemony
19.82 $
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32.36 $With VAT
0.54 $ / serving
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  • Castle factor increasing the absorption of vitamin B12
  • Bioactive, methylated forms of vitamin B12 and folates
  • Proper functioning of the nervous system
  • Improves memory and cognitive functions
  • Facilitation of blood-forming processes
  • Optimal energy metabolism
  • Decreased homocysteine level
  • Decreased feeling of fatigue
  • Regulation of metabolism
  • Proper development of the fetus
  • Hormonal balance

Douglas Labs B-complex with Metafolin® and Intrinsic Factor is a dietary supplement containing the complex of B-group vitamins, enriched in the so-called Castle factor, essential for the proper absorption of vitamin B12. A great advantage of the product is the presence of folates and vitamin B12 in the active, methylated form. The product contains 60 vegetarian capsules.

Vitamin B12 is a group of compounds – cobalamins. One of the forms of this vitamin is methylcobalamin, which contrary to the popular cyanocobalamin is the active form in the human organism. Vitamin B12 is essential for the proper functioning of all cells of the organism, primarily the nervous system, bone marrow and digestive system. It plays coenzymatic functions and takes part in the reactions of methylation. As a coenzyme, it activates enzymes catalyzing transformations of folic acid to the active methylated forms with the simultaneous remethylation of homocysteine to methionine, causing the decrease of homocysteine level in the organism.

Due to the presence of vitamin B12 only in animal products, people on a vegetarian diet should especially take care of proper supplementation in order to prevent deficiencies. Vitamin B12 cooperates with tetrahydrofolic acid in the production of erythrocytes in bone marrow. Clinical deficiency of methylcobalamin or folates is megaloblastic anemia.

Castle intrinsic factor (IF) is a glycoprotein conditioning the absorption of vitamin B12, produced in the stomach. Its deficiency of genetic defects prevent optimal activity of this vitamin despite its proper supply, leading to the development of megaloblastic anemia.

Metafolin is the active form of folic acid, directly influencing folate metabolism. It plays important functions in the metabolism of nucleic acids. By protecting chromosomes, folates may immunize cells to cancer-causing factors. Proper supply of folates is essential in pregnant women, who demonstrate increased need for this ingredient. Folates prevent the development of neural tube defects in the fetus, may protect from the occurrence of other malformations i.a. heart defects and condition proper development of the fetus.

The application of folates in the form of metafolin is important due to the relatively high frequency of the occurrence of MTHFR gene mutation, responsible for the transformation of folic acid in the active folate. In the presence of the mutated gene, the enzyme methylenetetrahydrofolate reductase is not produced, which may lead to undesired accumulation of folic acid in the organism. Metfolin is a “ready”, active form, thanks to which it does not require biochemical transformations in the organism.

Vitamin B1 (thiamine) influences the activity of enzymes, taking part in the metabolism of carbohydrates, i.a. transketolase and decarboxylase. Carbohydrates are the basic energy source for the nervous system. Deficiency of thiamine leads to disorders of work of this system, giving symptoms of the breakdown and decline of myelin sheath. Moreover, vitamin B1 protects from excessive aggregation of pyruvic acid and lactic acid in muscles, preventing the organism’s acidification.

Vitamin B2 (riboflavin), being the component of flavin enzymes, takes part in many reactions of oxidation and reduction. It is essential for the transformations of vitamin B6 to its active form. It has protective effect on the eyesight - it influences proper eye transparency and prevents the development of cataract. Vitamin B2 deficiency gives symptoms of skin lesions - acne, desquamation and lip cracking and disorders of the nervous system in the form of weakness, paresthesia or partial decline of the optic nerve.

Vitamin B3 (niacin) constitutes a component of coenzymes NAD and NADP, forming dehydrogenase enzymes, taking part in the reactions of tissue respiration, glycolysis, metabolism of nutrients (carbohydrates, proteins, fats) and the synthesis of some hormones, i.a. thyroxine or sex hormones. Niacin also influences the decrease of cholesterol level and triacylglycerols in blood and demonstrates antioxidant activity.

Vitamin B5 (pantothenic acid) is the component of molecules of many biologically active compounds, primarily coenzyme A (CoA). CoA takes part in key reactions conditioning energy balance of the organism. This compound is a carrier of acyl groups, essential for the proper course of metabolic processes, i.a. oxidation and the synthesis of fatty acids or the creation of citrates from acetic or oxalic acids. Deficiencies of vitamin B5 contribute to disorders of the work of the digestive system and nervous system, deterioration of the state of skin, inhibition of growth and disorders of the functioning of adrenals.

Vitamin B6 (pyridoxine) in the form of phosphate derivatives takes part in ca. 40 biochemical reactions, mainly amino acid transformations. It influences the metabolism of cholesterol and steroid hormones and optimizes the functions of the immune system. Its deficiency disturbs the synthesis of adrenaline and noradrenaline from tyrosine and phenylalanine, the transformations of glutamic acid in GABA and the synthesis of heme, contributing to the development of hypochromatic anemia.

Vitamin B7/H (biotin) mainly functions as a coenzyme of carboxylases - i.a. propionic carboxylase or acetyl-CoA carboxylase, taking part in the processes of gluconeogenesis, the synthesis of fatty acids and steroids. Biotin influences proper functioning of the nervous system, muscles and joints, supports well-being and thanks to the content of sulfur, it contributes to the improvement of the state of skin, hair and nails.

To sum up, Douglas Labs B-complex with Metafolin® and Intrinsic Factor is a dietary supplement containing highly assimilable forms of B-group vitamins in properly high doses. The preparation is recommended especially to people who lead an active lifestyle, perform intensive physical or intellectual work, in problems with memory and concentration, to vegetarians, after antibiotic-therapy, pregnant women, in the pre-conception period and as prophylaxis of civilization diseases.



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Container size: 60 capsulesServing size: 1 capsuleServings per container: 60
per portion (1 capsule)amount%DV
Vitamin B1 (Thiamine HCL)44 mg4000%
Vitamin B2 (Riboflavin-5-Phosphate)20 mg 1429%
Vitamin B3 (Niacinamide)50 mg 313%
Vitamin B6 (Pyridoxal-5-Phosphate)14 mg1,000%
Vitamin B9 (L-methylfolate, Metafolin®)400 mcg 200%
Vitamin B12 (Methylocobalamin)500 mcg 20000%
Vitamin B7 (Biotin)300 mcg 600%
Vitamin B5 (D-Calcium Pantothenate)50 mg 833%
Intrinsic Factor (from porcine)20 mg -

Other ingrednients

Microcrystalline cellulose, hydroxypropyl methylcellulose, magnesium stearate.

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Vitamin B3


Vitamin B3 (vitamin PP, niacin, nicotinic acid, nicotinamide) is niacinamide niacin. It is used in interaction with vitamins B1, B2 and B6 in the synthesis of hormones during lactation. It provides proper functioning of the brain and nervous system. It is helpful in inflammatory conditions of the skin. Required for synthesis of sex hormone, estrogen, testosterone, cortisone, and insulin. It does not lose its properties in the manufacturing and storage. The source of acquiring vitamins PP are both products of animal origin (the lean meat, eggs, fish) and vegetable origin (dates, figs, hazelnuts, plums).
Dosage: 2-12 mg / day for children, 14 mg / day for women, 16 mg / day for men and 17-18 mg / day for pregnant or nursing women.


Vitamin B6


Vitamin B6 (pyridoxine, pyridoxal, pyridoxamine) is soluble in the liquid. It participates in the metabolism of proteins, fats and carbohydrates. By reducing the amount of fat in the blood do not enable deposition of the body. It helps the absorption of magnesium and vitamin B12 (cobalamin). It works on the muscle antispasmodic and anti-inflammatory pain in the joints. It acts anti. It provides efficient operation of the brain. It increases energy increasing vigor of a man. The demand for vitamin B6 increases during pregnancy and breast-feeding infants. The natural product is: yeast, eggs, wheat germ, meat (liver), wheat bran, nuts, peanuts peanuts, soybeans. There is a hypothesis that can be synthesized by intestinal bacteria.
Deficiency of vitamin B6 causes abnormal metabolism of proteins, decrease in lymphocytes in the blood, causes a feeling of lethargy and fatigue intensifies.
Dosage: 1.5-2.5 mg daily (increased demand during pregnancy and lactation).




Metafolin® is a stable and bioactive form of folic acid with high bioavailability, patented by the German pharmaceutical company Merck KGaA.  After ingestion, the compound may be directly utilised by the body, irrespective of the presence of disorders (e.g. a MTHFR gene mutation) which hinder conversion of other forms of folic acid into their active forms. 

The efficacy of Metafolin® has been confirmed by numerous clinical studies. For instance, it has been demonstrated that this is the only form of folic acid which is capable of crossing the blood-brain barrier. What is more, Metafolin®has passed extensive toxicological safety testing.

In supplementation, Metafolin® is used primarily in women planning pregnancy or who are pregnant and individuals with methylation disorders and elevated homocysteine levels. Scientists also suggest that there is a correlation between folic acid deficiency in the cerebrospinal fluid and the risk of dementia and depression. Because of that, it may be effective in the prevention of neurodegenerative diseases and depression.

Metafolin® can be used not only in dietary supplements but also as an addition to drinks and food. 

Dosage: according to individual requirements for folic acid.   



Biotin (vitamin H, co-enzyme R) is in a group of B vitamins, due to the presence of sulphur compounds it is involved in the synthesis of ascorbic acid (vitamin C). Also synthesized in the intestines. It enhances the production of hormones and regulates cholesterol levels. It reduces muscle pain. It prevents hair loss and graying of hair. It soothes the skin inflammations. No toxic effects. Often combined with other B group vitamins and vitamin A. The natural sources of biotin are: whole grain bread, yeast, eggs (yolk), milk, brown rice and cheese.

Daily demand: 100-300 mg per day




Calcium (element chem. symbol Ca, atomic no. 20, the group of alkaline earth metals) is the basic building substance of bones and teeth, in which stored is 99% of the element, in the form of hydroxylapatite. When building bones and teeth, phosphorus is very important in the right proportion. It is a base-forming element and activator of many enzymes (ATPase) necessary to release the energy of ATP. It has a significant effect on blood clotting and regulates blood pressure and neuromuscular conductivity. Thanks to the reduced permeability of cell membranes, it soothes the symptoms of food allergies. Calcium is actively involved in the metabolism of iron interacts with vitamins A, C and D and phosphorus, magnesium. Natural source of calcium are animal products (dairy products, sardines, salmon, sprats eaten with bones) and plant products (nuts, soybeans, sunflower seeds). Absorption takes place in the small intestine (less in the colon), it has an effect on the level of lactose, insoluble fibre, organic acids, alkalinity (low pH). The best absorption have organic compounds (lactates, amino acid chelates etc.). Obstructing the absorption of calcium is caused by: phytic acid and oxalic acid as well as excess fat. Scientific studies have confirmed that the combination of calcium, magnesium, boron and vitamin D in dose 3 mg / 24h effectively prevent osteoporosis. Supplements on the market are both mono-preparation supplements (enriched with vitamin D3) and multi-component supplements, available at
Calcium deficiency disorders manifested in the construction of the bones (osteoporosis) and iron metabolism. The symptoms are: rickets, cramps and muscle tremor, osteoporosis.
Excess result
ing from an overdose of calcium supplements containing vitamin D3 for children and adults overdose of calcium (hypercalcemia). Symptoms of hypercalcemia are: lack of appetite, vomiting and constipation.
The dosage administered in various publications
are inconsistent: 800 - 1000 mg / 24 h (100 - 500 mg / 24h)

Intrinsic factor


Intrinsic factor (IF) is a kind of glycoprotein produced by the parietal cells of the stomach. It has a key role in the absorption of vitamin B12. After binding to intrinsic factor, the vitamin forms a special complex which can be absorbed in the small intensine.

Impaired production of intrinsic factor may be genetically determined, but it occurs equally often due to damage to the gastric mucosa caused by Helicobacter pylori infection. IF synthesis is also seriously inhibited by gastric parietal cell antibodies. IF deficiency limits the absorption of vitamin B12 and may consequently lead to major deficiencies and subsequent diseases.

Purified intrinsic factor, obtained from porcine gastric mucosa, is the most frequent form used in supplementation. It is added to preparations with vitamin B12 or B vitamin complexes to improve cobalamin absorption.

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