You hear about L-carnitine mainly in the fitness sector, as it is said to increase performance . It is also said to boost fat burning and is therefore often advertised as a weight loss product . What exactly is L-carnitine and is there any truth to this promise? At the end of the article we have provided you with a voucher for our L-carnitine . It's worth reading on! What is L-carnitine? Carnitine is an amino acid , but it is not used as a protein building block. The job of carnitine is to transport fatty acids into the mitochondria . These are small organelles inside the cell that are also known as the power plants of the cell because they produce a large part of the energy. The β-oxidation of fatty acids takes place in the mitochondria. Colloquially, this is called fat burning . This is where fat is converted into energy that the body can use for muscle movement, for example. [1] Like other amino acids, carnitine can be present as D-carnitine or L-carnitine . However, only L-carnitine is of biological importance. So when you read carnitine, you always mean L-carnitine, including in this article. At the end of the article we have a gift for you. It's worth reading on! Effect of L-carnitine Carnitine is popular as a dietary supplement because it is said to have positive effects. Above all, it is said to be able to increase fat burning and athletic performance. Does carnitine increase fat burning? Since carnitine is necessary for the transport of fatty acids into the mitochondria, where they are then “burned”, carnitine is often marketed as a fat burner that is supposed to help melt the fat around your hips. However, the body can produce the required amounts of carnitine itself (see below), and more carnitine does not necessarily mean more fat burning. The research is not clear on this point. Although there are some studies that show that supplementing with carnitine can promote weight loss , this is not considered proven. [2] Does carnitine improve athletic performance? Carnitine is also popular among athletes because it is said to increase performance . However, there is little research on this. For example, studies have shown that supplementation does not increase the performance of marathon runners or sprinters . [3] , [4] However, individual studies show a positive effect of carnitine on athletic performance. For example, a study with footballers in which carnitine improved endurance . [5] However, most of these studies did not examine whether participants were carnitine deficient (which is unlikely in healthy subjects). So if carnitine deficiency exists, it is certainly possible that carnitine could improve performance. Carnitine deficiency symptoms A carnitine deficiency can manifest itself through: [6] Tiredness and exhaustion Difficulty concentrating Muscle weakness and cramps Heart failure Susceptibility to infection Hypoglycemia Causes of carnitine deficiency Most people get most of their carnitine needs from food. Meat is by far the best source of carnitine, especially red meat such as beef and lamb. If necessary, the body can also produce carnitine itself. To do so, it needs the two essential amino acids lysine and methionine, and vitamin C , vitamin B6, vitamin B3 (niacin) and iron as cofactors. A diet low in carnitine therefore does not usually cause a carnitine deficiency. Rather, an inadequate intake of nutrients needed to produce carnitine can lead to a deficiency. A deficiency can also be promoted by an increased excretion of carnitine. The following groups of people are at increased risk of L-carnitine deficiency: Vegetarians and vegans Vegetarians and vegans consume significantly less carnitine than people who eat meat. Omnivores consume around 100-300 mg of carnitine daily through their diet. Vegetarians who eat eggs and dairy products only consume around 15-25% of this amount, and vegans 3-10%. [7] Vegetarians and vegans have lower carnitine stores in their muscles , but a meat-free diet alone is not a cause of a deficiency. [8] However, vegetarians and vegans are at increased risk of carnitine deficiency because they tend to consume less of the amino acids methionine and lysine than people who eat meat. [9] Cancer patients Approximately 80% of cancer patients have a carnitine deficiency in advanced stages of the disease. [10] This is often due to malnutrition. They do not consume enough meat and nutrients that are needed as cofactors for carnitine production. Chemotherapy can also lead to increased excretion of carnitine. Studies show that carnitine supplementation can counteract muscle loss and improve the overall health of cancer patients. [11] People with renal insufficiency In the case of renal insufficiency , the kidneys have problems recycling carnitine. As a result, it is excreted in increased amounts via the urine and a deficiency can easily occur. [12] Diabetes patients Patients with type 2 diabetes (so-called adult-onset diabetes) often have a carnitine deficiency. However, it is not entirely clear whether a carnitine deficiency promotes diabetes or whether diabetes causes the deficiency. [13] People who take antibiotics over a long period of time Long-term use of pivalic acid-based antibiotics , such as pivampicillin , can cause carnitine deficiency, probably by either inhibiting absorption or impairing its own synthesis. [14] Foods with L-carnitine L-carnitine is mainly found in meat , but it can also be found in other foods . The following foods contain L-carnitine: [15] Groceries mg carnitine per 100 g Meat extract 3686 veal 69.7 - 105 beef 45 - 143 Wild 35 - 193 Lamb or mutton 16.7 - 190 pork 14.4 - 24 poultry 4.3 – 13.3 Fish and seafood 1.7 – 13.2 Mushrooms 1.3 - 15 Milk and milk products 0.6 – 12.7   Buy L-Carnitine Supplementation with L-carnitine can be useful in the case of a carnitine deficiency in order to compensate for deficiencies. Risk groups can also benefit from a carnitine supplement to prevent a deficiency . When buying, you should pay attention to the form in which L-carnitine is available. L-carnitine esters, such as acetyl-L-carnitine and lauroyl-L-carnitine, have a lower bioavailability than other forms. [16] This means that the body cannot absorb and use it as well. Viktilabs' L-carnitine contains free L-carnitine as well as L -carnitine tartrate , both of which have a high bioavailability . The capsules are vegan . Conclusion: Carnitine is not an essential nutrient, but a deficiency is still possible Carnitine has important functions in fat metabolism. The body can produce carnitine itself, but a deficiency can still occur. Cancer patients in particular are often affected by a deficiency. But vegans and people with kidney problems are also often not well supplied with L-carnitine. Supplementing with high-quality L-carnitine can help to compensate for or prevent a deficiency. We at +Viktilabs have a 15 % coupon for our L-Carnitine provided and hope to bring you joy. Simply copy the voucher code " CARNITIN+V15 " and enter it at checkout. Click here for the product ________________________________________________________________________   [1] https://ods.od.nih.gov/factsheets/Carnitine-HealthProfessional/ [2] https://pubmed.ncbi.nlm.nih.gov/31743774/ [3] https://link.springer.com/article/10.1007/BF00334420 [4] https://www.thieme-connect.de/products/ejournals/html/10.1055/s-0035-1547580 [5] https://pubmed.ncbi.nlm.nih.gov/24263659/ [6] https://www.thieme.de/de/naturheilverfahren/l-carnitin-portraet-einer-aminosaeure-92804.htm [7] https://www.thieme-connect.de/products/ejournals/html/10.1055/s-0035-1547580 [8] https://academic.oup.com/ajcn/article/94/3/938/4411875 [9] https://pubmed.ncbi.nlm.nih.gov/11043928/ [10] https://pubmed.ncbi.nlm.nih.gov/15591014/ [11] https://pubmed.ncbi.nlm.nih.gov/29737795/ [12] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6893685/ [13] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5856836/ [14] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2399489/ [15] https://www.thieme-connect.de/products/ejournals/html/10.1055/s-0035-1547580 [16] https://pubmed.ncbi.nlm.nih.gov/15830915/

Vitamin D is also widely known as the sunshine vitamin , because the sun is the most important source for the production of vitamin D. However, according to a study by the Robert Koch Institute , more than half of Germans are not optimally supplied with vitamin D. ¹ Here you will learn how to recognize a possible deficiency in you, how it arises and what you can do about it. We at +Viktilabs have put together a discount code for you on all our products that contain vitamin D3 . You can find this discount code further down in the article. What is vitamin D? First we need to clarify something: Vitamin D is not strictly speaking a vitamin, but a hormone . Our body can produce it itself with the help of solar radiation. The UV-B rays in sunlight ensure that a precursor of vitamin D is converted into vitamin D3 . You can also find this form of vitamin D in high-quality food supplements. Vitamin D is vital because it fulfills many functions in the body. For example, it is needed for the absorption of calcium and phosphorus . As a result, it helps maintain healthy bones . And our immune system also needs vitamin D to function normally. It is also involved in the production of serotonin ² . This is a neurotransmitter in the brain that transmits signals between nerve cells. It is also known as the “feel-good maker” because it can activate the reward center of our brain. These are the symptoms of a vitamin D deficiency People suffering from a vitamin D deficiency often show the following typical symptoms: ³ • Susceptibility to infection • Muscle cramps and weakness • frequent exhaustion • mild irritability • Depression and other mental disorders • Bone problems Bone problems are one of the most common symptoms of vitamin D deficiency. Even in children, it can lead to softening of the bones, known as rickets . In older people, a lack of vitamin D can lead to osteoporosis . This is the medical term for a reduction in bone mass, which causes bones to become brittle. The good news is that bone problems only occur when there is an acute, long-term deficiency. All other symptoms, however, can occur even if the vitamin D supply is not optimal. Causes of vitamin D deficiency There are a number of possible reasons why you might be suffering from a vitamin D deficiency: 1. Too much time indoors Most of us spend most of our day indoors because of our jobs. The only time we see the sun is outside the office, on the way to work or in our free time in the evening. In winter, we don't even see daylight on these occasions. The skin hardly has a chance to produce vitamin D. ⁴ 2. Excessive use of sunscreen Too much sun can cause sunburn and skin cancer . That's why many of us tend to use excessive amounts of sunscreen . The downside: the skin can no longer produce vitamin D efficiently. ⁵ 3. Dark skin tone The darker your skin tone, the more susceptible you are to a vitamin D deficiency. Dark skin does not let sunlight through as well. The result: less vitamin D is produced. ⁶ 4. Taking certain medications Some medications affect vitamin D metabolism. The body is then unable to use the vitamin D produced. This can result in a deficiency. The following medications, for example, can affect this metabolism: antiepileptics (for the treatment of epilepsy), statins (for the treatment of cardiovascular diseases) and cytostatics (for the treatment of cancer). ⁷ 5. Gastrointestinal, liver and kidney diseases Gastrointestinal diseases can make it difficult to absorb vitamin D , which can quickly lead to a deficiency. ⁸ Liver and kidney diseases also promote a vitamin D deficiency because the vitamin D produced in the skin still has to be converted into an active form in these organs. This process is more difficult in these diseases. ⁹ ¹⁰ 6. Old age Vitamin D synthesis in the skin decreases with age . Therefore, older people are at higher risk of vitamin D deficiency. And because older people also tend to spend less time outdoors , natural sunlight cannot compensate for this deficiency. They are also more likely to take medications that can affect vitamin D metabolism . For this reason, older people are at high risk of vitamin D deficiency. ¹ ¹ How to meet your vitamin D needs There are three strategies to meet your vitamin D needs and prevent a deficiency: 1. Go out into the sun We cover around 80% of our vitamin D needs with the help of sunlight . However, this is a bit of a balancing act: On the one hand, we need a lot of direct sunlight to produce enough vitamin D. On the other hand, too much sun can also cause skin damage . The trick is to go out into the sun very regularly, but only for short periods of time. The length of time you spend in sunlight depends on how sensitive your skin is to light. As a rule of thumb, spend no more than half the time in the sun that would cause you to get sunburn. It's best to do this every day, but at least 2-3 times a week. 2. Take foods containing vitamin D as a supplement Unfortunately, there are not many foods that contain significant amounts of vitamin D. Nevertheless, part of the vitamin D requirement can be covered through food. The best source of vitamin D is fish with a high fat content , such as mackerel , herring and halibut . ¹ ² But eggs , avocado and mushrooms also contain some vitamin D. ¹³ ¹⁴ ¹⁵ 3. Consider supplementing with a vitamin D supplement Since more than half of Germans are not optimally supplied with this important hormone, supplementing the diet with vitamin D - especially in winter - can be useful. At this time of year, the risk of developing a deficiency is very high because vitamin D cannot be produced in the skin in our latitudes. Conclusion: Many people cannot meet their vitamin D needs naturally Vitamin D is essential for our health . Our immune system needs it to function and it helps maintain healthy bones . Ideally, you should meet your vitamin D needs naturally through the sun . However, since more than half of Germans do not have an optimal supply of vitamin D, it is likely that many people would benefit from supplementation . As promised, you will receive a 15% voucher on all our products that contain vitamin D3. Simply copy the code VITAMIND15+V and enter it at checkout. To the products! _________________________________________________________________________ [ ¹ ] https://www.rki.de/SharedDocs/FAQ/Vitamin_D/Vitamin_D_FAQ-Liste.html [²] https://faseb.onlinelibrary.wiley.com/doi/full/10.1096/fj.14-268342 [³] https://www.ncbi.nlm.nih.gov/books/NBK532266/ [ ⁴ ] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4641290/ [⁵] https://pubmed.ncbi.nlm.nih.gov/23882939/ [⁶] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4067096/ [⁷] https://pubmed.ncbi.nlm.nih.gov/30112988/ [⁸] https://pubmed.ncbi.nlm.nih.gov/18290722/ [ ⁹ ] https://pubmed.ncbi.nlm.nih.gov/17222588/ [ ¹⁰ ] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4571143/ [ ¹¹ ] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2776629/ [ ¹² ] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2698592/ [¹³ ] https://fdc.nal.usda.gov/fdc-app.html#/food-details/562115/nutrients [ ¹⁴ ] https://fdc.nal.usda.gov/fdc-app.html#/food-details/578012/nutrients [ ¹⁵ ] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6213178/

Vitamin C is probably the best-known vitamin because it is said to prevent and fight colds. Especially during the cold season, we are bombarded with advertisements for products containing vitamin C that are supposed to strengthen our immune system. Why is vitamin C so important, how can you prevent a deficiency and which foods are particularly rich in vitamin C? Here you will find all the important information. It’s worth reading on: We have created a discount code for you on our Vitamin C. You can find this discount code further down in the article. What is vitamin C? The chemical term for vitamin C is ascorbic acid . It is an essential nutrient . This means that we cannot produce vitamin C ourselves and therefore must ingest it through food. Vitamin C is a water-soluble vitamin and therefore cannot be stored in the body for long. We can only avoid deficiency symptoms by consuming sufficient amounts every day. What does vitamin C do in the body? Ascorbic acid is involved in many metabolic processes in the body. It is particularly important for the immune system . It contributes to its normal function and thus protects us from infections . In addition, ascorbic acid is involved in the formation of collagen - an important protein in connective tissue that is a component of skin , bones , tendons , ligaments , cartilage and blood vessels . Vitamin C also has an antioxidant effect and helps to protect cells from oxidative stress caused by free radicals . Vitamin C is also important for the usability of other nutrients: it increases iron absorption in the body and is needed for the production of carnitine , which ensures a healthy energy metabolism. [1] Symptoms of vitamin C deficiency We all know it from old pirate films, in which sailors fell ill with scurvy after a long time at sea. This is probably the best-known symptom of a vitamin C deficiency. If you don't eat fresh fruit and vegetables for months, you develop mouth rot , which causes severe bleeding of the gums and, after a while, can even cause your teeth to fall out . This acute form of vitamin C deficiency is very extreme and is rare these days. However, studies show that around 25% of the population is not optimally supplied with vitamin C. [2] This can lead to early symptoms. [3] These symptoms can be very unspecific, meaning that the causes of these complaints are wide-ranging. If you have one or more of the following symptoms, this does not necessarily mean that you have a vitamin C deficiency. Only a blood test at the doctor's can reveal a vitamin C deficiency. The usual symptoms are: reduced performance increased exhaustion mild irritability increased susceptibility to infection poor wound healing Limb and joint pain increased need for sleep Foods with the highest vitamin C content According to the DGE, the recommended daily requirement of vitamin C is 110 mg for men and 95 mg for women . Pregnant and breastfeeding women have a slightly increased requirement of 105 mg and 125 mg respectively. [4] Just 100 g of many types of fruit and vegetables contain so much vitamin C that they sometimes even exceed the daily requirement. However, these figures only apply to raw, unprocessed foods, as the vitamin C content decreases when heated . The table below shows which natural foods are particularly rich in vitamin C. [5] Surprisingly, oranges don't even make it into the top 10 and lemons are by no means the top performer either! mg vitamin C per 100g paprika 183 Acerola cherry 1677 Blackcurrants 181 Parsley 133 Kale 120 kiwi 93 broccoli 93 Cauliflower 88 Brussels sprouts 85 Lemons 77 Causes of vitamin C deficiency We usually get enough vitamin C from our daily diet. Even people who don't like fruit and vegetables are rarely affected by deficiency symptoms, as you can still get enough vitamin C even with small amounts. So how can a vitamin C deficiency arise? A vitamin C deficiency occurs when the body cannot properly absorb or utilize ascorbic acid from food. Certain diseases and living conditions can be responsible for this: [6] Medicines such as birth control pills, aspirin, antidepressants, antibiotics and diabetes medications Alcoholism, smoking, drug abuse Gastrointestinal diseases chronically elevated blood sugar Increased blood sugar – the underestimated cause of insufficient vitamin C supply In particular, chronically elevated blood sugar causes a vitamin C deficiency. This is because the vitamin competes with sugar for absorption into the cells. [7] As long as blood sugar is elevated, the cells cannot absorb vitamin C efficiently from the blood. If blood sugar rises briefly after eating, which is completely normal, this is not a problem. It only becomes problematic when the body has difficulty regulating blood sugar and it is therefore too high for too long . In addition, high blood sugar causes oxidative stress, which increases the need for vitamin C even further. In diabetes, blood sugar is not adequately controlled and the disease is therefore a common cause of vitamin C deficiency. [8] Vitamin C preparations Vitamin C is available in the form of tablets , capsules and many other forms. Liposomal vitamin C is relatively new and innovative. The liposomes , which you can imagine as fat bubbles , enclose the vitamin C in a protective manner and thus reduce the breakdown during the digestive process. This enables the body to absorb more vitamin C. [9] Conclusion: Many people are not optimally supplied with vitamin C Vitamin C is an important antioxidant and contributes to the normal functioning of the immune system . It is found in abundance in fruit and vegetables, so the risk of deficiency in healthy people is rather low. However, illnesses such as diabetes and the use of certain medications can impair the absorption of vitamin C , so supplementary supply can be useful. As promised, you will receive a 10% voucher for our Vitamin C. Simply copy the following code and enter it at checkout: VITAMINC10 [1] https://www.ncbi.nlm.nih.gov/books/NBK499877/ [2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1448351/ [3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2567249/ [4] https://www.dge.de/forschung/referenzwerte/vitamin-c/ [5] https://nutritiondata.self.com/foods-000101000000000000000-w.html [6] https://www.ncbi.nlm.nih.gov/books/NBK499877/ [7] https://pubmed.ncbi.nlm.nih.gov/16118484/ [8] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5622757/ [9] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4915787/

If you are constantly sick or have a constant cold, you probably have a weak immune system. Pathogens such as bacteria , viruses and fungi are considered to be the cause of infections . However, our environment is teeming with pathogens: we are constantly exposed to them. The question of whether we fall victim to them and catch a cold, for example, depends on how well our immune system can fight off harmful invaders. IT'S WORTH READING: WE HAVE CREATED A DISCOUNT CODE FOR YOU ON THE PRODUCTS OF THIS ARTICLE OFFERED IN THE SHOP. YOU CAN FIND IT AT THE END OF THE ARTICLE. With these 5 tips you can strengthen your immune system and reduce your susceptibility to infections: 1) Supply your immune system with vitamins and minerals Your immune system needs a number of vitamins and minerals to function properly. If you are lacking just one of these nutrients, your immune system may be weakened and you may become sick more easily. The following nutrients are particularly important: Vitamin C Vitamin C supports the immune system in several ways. First, it contributes to collagen formation and thus supports the function of the skin . The skin is the first barrier against harmful invaders. In addition, vitamin C stimulates the proliferation of immune cells that produce antibodies . Antibodies recognize and bind to pathogens, allowing the body to easily get rid of them. [1] The daily requirement of vitamin C is 95 mg for women and 110 mg for men . [2] You can easily reach these amounts if you eat fresh fruit and vegetables every day. In our article about vitamin C you will learn more about this important vitamin and which foods are particularly rich in it. zinc Zinc supports the immune system by contributing to the development and function of immune cells. [3] The daily requirement of zinc is 7-16 mg . [4] The requirement depends on how much grains and legumes you eat. This is because these foods contain phytic acid, which binds zinc and thus reduces the absorption of this mineral. [5] B vitamins : vitamin B6, folic acid, vitamin B12 The intestine plays an important role in the immune system. The B vitamins B6, B12 and folic acid (vitamin B9) primarily support the part of the immune system that takes place in the intestine. Vitamin B6 helps immune cells to reach the intestine. Folic acid promotes the survival of immune cells in the small intestine and vitamin B12 helps to strengthen the intestinal barrier. [6] 2) Improve your gut health As mentioned, a healthy gut is the be-all and end-all when it comes to strengthening the immune system. The gut is an internal organ, but it is also the gateway to the outside world . What you eat passes through the mouth, esophagus and stomach into the gut, where most of the nutrients are absorbed through the mucous membrane. The gut barrier therefore represents a hurdle for pathogens. In addition, gut bacteria support the function of immune cells. [7] You can support your gut health with fermented foods such as sauerkraut and kombucha , which provide valuable probiotic bacteria and thus support your gut flora. Fiber-rich foods, on the other hand, provide food for beneficial gut bacteria. 3) Spend enough time in the sun The sun is the most important source of vitamin D. Vitamin D supports the normal function of the immune system. Scientists even suspect that a poor supply of vitamin D in winter is one reason why we are so susceptible to flu viruses at this time of year. [8] However, especially in our latitudes, it can be a challenge to meet vitamin D requirements naturally. A study by the Robert Koch Institute has shown that more than half of Germans are not optimally supplied with vitamin D. [9] These people would most likely benefit from supplementation with high-quality vitamin D. In our article about vitamin D you will learn why the sunshine vitamin is so important and how you can prevent a deficiency. 4) Make sure you get enough sleep Restful sleep helps the body to regenerate and thus strengthens the immune system. A study has shown that people who sleep less than 7 hours have a 3 times higher risk of catching a cold than people who sleep 8 hours or more. [10] The hours before midnight are particularly valuable, so try to go to bed as early as possible. 5) Reduce stress Stress is not always bad. Stress releases energy that helps you perform at a particularly high level in an exceptional situation. For our ancestors, a dangerous situation was a typical trigger for stress. In such a moment, escaping the danger has the highest priority. All available energy is used for this and many other body functions, such as the immune system, are temporarily shut down. If this only happens occasionally for a short period of time, it is not a problem. Long-term stress, on the other hand, can permanently weaken the immune system , making you more susceptible to infections. [11] For this reason, you should try to reduce stress in your everyday life as much as possible. Conclusion: The immune system can be strengthened with simple means A strong immune system is the result of a healthy lifestyle . Our immune system needs vitamins and minerals , a healthy gut and restful sleep to function optimally. Too much stress, an inadequate supply of nutrients and a diet that is harmful to the gut, on the other hand, weaken the immune system. It is not always easy to meet nutritional needs through diet. Targeted supplementation with essential vitamins and minerals can help to correct and prevent deficiencies. In the Viktilabs online shop you will find nutritional supplements of the highest quality and purity. As promised, you will receive a 10% voucher on the following products: Vitamin B complex, Vitamin B complex Forte, Vitamin B12 , Vitamin C , Vitamin D, Zinc, Zinc/Copper Simply copy the code IMMUNSYSTEM10 and enter it at checkout. To the products! [1] https://pubmed.ncbi.nlm.nih.gov/29099763/ [2] https://www.dge.de/forschung/referenzwerte/vitamin-c/ [3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2277319/ [4] https://www.dge.de/forschung/referenzwerte/zink/ [5] https://pubmed.ncbi.nlm.nih.gov/10801947/ [6] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7019735/ [7] https://www.sciencedirect.com/science/article/pii/S2452231718300095 [8] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2870528/ [9] https://www.rki.de/SharedDocs/FAQ/Vitamin_D/Vitamin_D_FAQ-Liste.html [10] https://pubmed.ncbi.nlm.nih.gov/19139325/ [11] https://pubmed.ncbi.nlm.nih.gov/18279846/