Introduction
Every child already knows that vitamins should be important components of food and are good for the body. The same must apply then nevertheless also to the Vitamin D. ? Or is too much of the actually necessary substance possible?
The daily dose recommended by doctors and nutritional societies is 20ug (20 millionths of a gram) for all people. The guideline values for infants in their first year of life are limited to 10ug a day, depending on their young age. Normally, every healthy body produces about 80-90% of the vitamin D it needs in the skin itself under sunlight.
Only a small part of the daily requirement is absorbed through food. Fatty fish species and cod liver oil play a leading role in this, while some other foods play a subordinate role. Because many people are now less exposed to the sun due to changed lifestyles, some speak of social vitamin D deficiency and special dietary supplements (bsw.
Vigantoletten) are booming; many health-conscious people take these willingly, many doctors gladly prescribe them. In most cases, this can be seen as positive, but not in all cases: Here too, as so often: the dose makes the poison. Even such vital things as vitamin D can cause negative side effects under certain circumstances. Especially with some specific vitamins, namely the fat-soluble ones, one can even be poisoned. But how do you recognize a vitamin D overdose and how should you act then?
Causes
Vitamin D belongs together with vitamins E, K and A (note: E-De-K-A) to the fat-soluble vitamins. Unlike the others, which are water-soluble, these need a fat-containing carrier to be absorbed. In the body they are then bound to certain transport molecules in order to be able to float freely in the blood.
However, they can also be deposited in the fatty tissue and accumulate there, so that the amount in the body is constantly increasing. Water-soluble vitamins, if they are present in larger quantities than they are needed, are released into the urine via the kidneys and excreted in this way (dissolved in water). In the case of fat-soluble vitamins, this is only possible after passing through a number of degradation steps, which are much more specific.
A separate enzyme group is responsible for the breakdown of vitamin D, which converts the excess vitamin D so that it can be released into the stool with the bile. In general, however, this breakdown is not necessary at all, as the majority of the vitamin D required is produced by the body itself. This production is regulated and increased or inhibited as required.
Unpleasant symptoms associated with vitamin D occur in almost all cases only if food supplements are used improperly, for example if excessive amounts are taken. The symptoms of a vitamin D overdose include many rather unspecific things, but when taken as a whole they can provide the decisive clue. These include loss of appetite and weight loss, vomiting, constipation, abdominal cramps, high blood pressure, psychosis, but also muscle and tendon pain and headaches.
In addition, cardiac arrhythmia can occur in some patients. Since vitamin D increases the absorption of calcium in the intestine and additionally draws calcium from the bones, too much calcium inevitably appears in the blood. One speaks of a hypercalcaemia.
Thus it remains only a question of the time until also in the urine a large quantity of calcium appears, since the organism is endeavored now to excrete the surplus calcium. Affected persons usually also show hypercalciuria (increased urinary calcium level). Both of these conditions cause serious problems over a long period of time: conspicuous kidney damage occurs, which is accompanied by an increased feeling of thirst and large amounts of drinking (polydipsia) and frequent urination (polyuria).
In addition, calcium deposits are found in almost all joints, soft tissues and muscles, causing the above-mentioned pain. A long-term overdose of vitamin D can also lead to osteoporosis of the bones. Vitamin D overdoses in children usually show similar symptoms to those in adults.
In addition, however, growth disturbances and a permanent increase in body temperature are common. A permanent and/or very severe vitamin D overdose can lead to death. Both the overdose but also the lack of vitamin D can lead to diarrhoea.
Under certain circumstances, intervention by the doctor may be necessary. Hair loss itself is always first observed as a symptom of the body, which signals that something is wrong.The cause of this symptom can be due to many different diseases. Not every type of hair loss is necessarily related to vitamin D and even an overdose of it.
On the contrary, hair loss – if it is related to vitamin D – is more a sign of a vitamin D deficiency! Too little vitamin D leads not only to a decrease in bone density with a resulting increased risk of fracture (osteoporosis), but also to a shortening or postponement of the hair growth phases. The result is a faster loss of hair, which can even lead to bald spots.
The vitamin D as an important and elementary food component and endogenous product is important for many functions of the human organism such as bone formation. A natural supply via food and the body’s own production usually show no side effects. If a sufficient quantity is already available, the body automatically shuts down its own production so that no overdosage can occur. Unpleasant side effects (as described under symptoms, see above) are almost exclusively caused by dietary supplements containing much higher doses than those found in naturally occurring foods.