VITALS VITAMIN B12 CAPSULES 100 CAPSULES

Vitamin B12 1000 mcg Capsules from Vitals consists of vegetarian capsules with the biologically active forms methylcobalamin and adenosylcobalamin (also called dibencozide). These are the forms in which vitamin B12 occurs in food and is used by the body. Many other vitamin B12 products use cyanocobalamin, a synthetic form that does not occur in nature.

This product is specifically suited for people who prefer to use a B12 supplement in capsule form, without flavors and sweeteners. If desired, the capsule can be opened and the powder sprinkled under the tongue. However, this is not strictly necessary. Taking the entire capsule, preferably on an empty stomach, is also effective.

Benefits of Biologically Active B12
In oxidative stress, supplementation with a reduced form of vitamin B12 (such as methylcobalamin) may have advantages over an oxidized form of vitamin B12 (such as cyanocobalamin). Research also suggests that a greater improvement in vitamin B12 status occurs after taking biologically active B12 than after taking cyanocobalamin; more B12 is stored in the liver and less B12 leaves the body in the urine (longer half-life). Thus, bioavailability is greater.

Vitamin B12 absorption
The absorption of vitamin B12 from food is a complex process (see figure 1). In the stomach, vitamin B12 is released from dietary proteins and temporarily bound to transport proteins (also called R-proteins or transcobalamin I) that occur in saliva and mucus from the esophagus and stomach. In the duodenum, pancreatic proteases (digestive enzymes produced by the pancreas) release vitamin B12 from these R-proteins, after which the vitamin is bound to 'intrinsic factor' (IF), a specific protein that is produced in the stomach and is necessary for the absorption of vitamin B12. Subsequently, in the last part of the ileum, vitamin B12 is taken up into the enterocytes (intestinal cells) via active transport after binding to certain receptors, provided that the vitamin is bound to IF. In the enterocytes, IF is broken down and the released vitamin B12 is coupled to other transport proteins: transcobalamin I and transcobalamin II. This complex is then released into the blood plasma.

How the Body Uses Vitamin B12
In the blood, 20-25% of vitamin B12 is bound to transcobalamin II. Only vitamin B12 that is bound to this protein is absorbed into the body cells (see figure 2). In the lysosomes of the cell, vitamin B12 is released from transcobalamin II and converted into methyl- or adenosylcobalamin. (Lysosomes are vesicles in the cytoplasm in which certain substances are broken down to be reused or excreted.) Methylcobalamin is mainly needed in the blood plasma, cytoplasm and cerebrospinal fluid, while adenosylcobalamin is needed in the tissues and mitochondria.

In the form of methylcobalamin (in cytoplasm), vitamin B12 is a cofactor in the conversion of homocysteine ​​into methionine by the enzyme methionine synthase (see figure 2). In this process, methylcobalamin gives up its methyl group to homocysteine ​​and the remaining cobalamin receives a new methyl group that is given up by 5-methyltetrahydrofolate. And then the cycle starts again. This process is also called (re)methylation. Methionine is in turn mainly used for the production of S-adenosylmethionine (SAMe), which is involved as a primary methyl donor in the production of DNA, RNA, myelin, phospholipids, proteins and neurotransmitters (including serotonin and dopamine). In this way, methylcobalamin can contribute to normal cell division and the production of red blood cells. And it is also necessary for normal brain and nerve functions, and therefore good for concentration, memory and mood. Through its involvement in DNA synthesis and protein synthesis, vitamin B12 also influences the activation of certain immune cells and thus the normal functioning of the immune system.

In the form of adenosylcobalamin (in the mitochondria), vitamin B12 is involved in the conversion of methylmalonyl-CoA to succinyl-CoA (see figure 2), which plays a role in the citric acid cycle, a series of biochemical reactions that provide energy metabolism at the cellular level. In this way, vitamin B12 supports energy levels and can help reduce fatigue.

Active and passive recording
The active absorption of vitamin B12 from food is very efficient, but due to saturation of receptors the absorption percentage decreases rapidly when the vitamin B12 intake increases. From a few micrograms of vitamin B12 25 to 65% is absorbed, from 25 mcg only 5%. When vitamin B12 is not coupled to IF, it can be absorbed via passive diffusion* (along the entire length of the gastrointestinal tract), but this form of absorption is very inefficient. In the absence of IF only 1% of vitamin B12 is absorbed. In addition, vitamin B12 that is not coupled to IF is broken down more quickly by protein-splitting enzymes and intestinal bacteria. This means that normal production and function of IF is of great importance for the active absorption of vitamin B12.

In certain situations, it may be necessary to use a high-dose vitamin B12 supplement (with a dosage of 500-2000 mcg) to provide additional support. At least a relevant portion of this can then be absorbed via passive diffusion to further ensure that B12 absorption is sufficient. It is recommended to use vitamin B12 in combination with folate and other B vitamins or a complete multi.

* Passive diffusion is a process by which substances can move across the cell membrane without having to be coupled to anything to be actively transported.

Permitted health claims:

• plays a role in the cell division process
• is important for the formation of red blood cells
• is important for energy metabolism
• contributes to normal homocysteine ​​metabolism
• has a positive effect on the functioning of the immune system
• contributes to normal psychological functioning
• may help reduce fatigue
• contributes to the normal functioning of the nervous system

Anti-caking agent (rice fibre), vegetable capsule (pullulan, from fermented cassava starch), adenosylcobalamin, methylcobalamin.