Water-soluble vitamins Part I: Vitamin C in focus
No other vitamin is mentioned more often when it comes to immune defence: vitamin C. Is this substance, which is chemically called ascorbic acid and is known to be found in citrus fruits, more of a marketing programme, a miracle cure or a little bit of everything? We will now get to the bottom of this very question in order to better classify and understand the so popular vitamin.
Five main facts at the bottom of this article!
Vitamin C belongs to the water-soluble vitamins
Vitamin C is one of the water-soluble vitamins. Unlike fat-soluble vitamins, these chemical compounds are not stored separately in the body. Consequently, the part of the water-soluble substances that cannot be utilised is immediately excreted through the kidneys and consequently through the urine. An overdose is therefore difficult to cause. Water-soluble vitamins are mostly precursors of cofactors. The cofactors play an important role in biochemical reactions for a proper process. Characteristic for this vitamin class is the unrestricted absorption, without further food components in the upper small intestine by the small intestine cells.
Cell protection as an outstanding task
Vitamin C assumes numerous functions in our body. The most important property of this substance is that it acts as a so-called antioxidant. Vitamin C is therefore able to “catch” damaging free radicals and thus provide effective cell protection. In this context, it should be mentioned that ascorbic acid is involved in the regeneration of the cell-protecting vitamin E. This promotes cell protection because vitamin E, as a “component” of our cell membranes, protects precisely the outer boundaries of our cells from harmful free radicals. You can read more about vitamin E in this article.
Vitamin C is involved in numerous reactions
But the importance of the vitamin is not only based on cell protection. Vitamin C is needed for a large number of the body’s own biochemical processes. Accordingly, this substance is jointly responsible for the proper course of certain chemical reactions. Especially in the context of collagen biosynthesis, vitamin C is indispensable. Without ascorbic acid, defective collagen fibres would consequently result, which in turn would affect our connective tissue. It is also worth mentioning its role in the synthesis of serotonin, steroid hormones and noradrenaline.
The dose makes the difference: Know the recommended daily amount
According to the German Nutrition Society, women should consume 95 mg and men 110 mg of vitamin C daily so that the body can optimally perform all the functions listed. This information applies explicitly to adults. According to the recommendation, children and adolescents need considerably less. Depending on the age group, the amount to be taken in is 20 to 95 mg per day.
It should also be noted that vitamin C can hardly be overdosed. It is a water-soluble vitamin that does not pose a great risk of accumulation even at excessive doses. Hypervitaminoses are therefore not known, because excess amounts are simply excreted. Furthermore, the intestinal barrier plays a major role in the oral uptake of vitamin C. Even at high doses, there is no risk of vitamin C being absorbed. Even at high doses, a toxic vitamin C level is never reached because absorption through the intestine is limited. This is exactly why it is important in the context of cancer research, where one tries to find out whether vitamin C can have a harmful effect on tumours, to reach a pharmacological or therapeutic dosage. However, this can only be achieved by intravenous administration.
Too low a vitamin C intake can lead to complaints
Adherence to the daily recommended vitamin C dose is primarily to achieve the required minimum amount. A slight deficiency can cause weakness, fatigue and increased susceptibility to infections. Chronic deficiencies of this vitamin unfortunately lead to the disease called scurvy. Ultimately, although it is an extremely rare phenomenon, it encompasses a range of symptoms. The symptoms are primarily due to defective collagen synthesis. Symptoms of scurvy include bleeding gums, tooth loss and petechiae (bleeding into the skin and mucous membranes).
Vitamin C is important but not a miracle cure
There is no doubt that vitamin C plays an important role in cell protection as well as in supporting the immune system. Maintaining the necessary daily amount is not only important to sustain essential reactions, but also to avoid adverse effects such as weakness and fatigue. Vitamin C is not a miracle cure, but it is still considered a chemical compound for our biological system that should not be underestimated.
Five facts: You should definitely know these facts
1. Vitamin C is a water-soluble vitamin. This class of vitamins is difficult to overdose on, as too much is immediately excreted and not utilised by the body.
2. The vitamin plays an outstanding role in cell protection. It scavenges free radicals and participates in the regeneration of vitamin E
3. Vitamin C is involved in numerous biochemical reactions. Especially in the context of collagen synthesis, vitamin C is considered an indispensable component.
4. For various reasons, vitamin C can hardly be overdosed. In the context of cancer research, however, attempts are being made to exploit a toxic effect on tumours through high vitamin C concentrations.
5. Vitamin C deficiencies are extremely rare, but are associated with some complications such as tooth loss
Text sources:
(1) Bässler, Vitamins, 2nd edition, 1981; Rassow et al, Biochemistry, 4th edition, 2016.
(2) Königshoff and Brandenburger, Biochemistry, 4th edition, 2018.
(3) https://www.dge.de/wissenschaft/referenzwerte/vitamin-c/
(4) Roa et al, Therapeutic Use of Vitamin C in Cancer: Physiological Considerations, 2020.
(5) Horn, Biochemistry, 7th edition, 2018.
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