What are supplements really good for?
Healthy, fit, powerful - who would not want to be? It is hardly surprising that the tantalizing advertising messages for dietary supplements meet with open ears. According to the National Consumption Study II, every third woman and one in four men in Germany take such preparations; around 650 million euros were spent on this in 2008. For many, they are just like the daily bread. The most popular are the funds for people between 35 and 50 years. They should increase well-being and vitality, reduce stress and aging processes, prevent or even prevent illnesses. But what can you really do? We talked to experts and give answers to the most important questions.
What are dietary supplements?
Vitamins, minerals and trace elements, individually or in any combination, plant extracts from acerola to hawthorn, amino acid and fat compounds, preparations for the eyes, bones, memory or immune defense, against stress, menopausal symptoms or loss of vitality - the abundance of dosages, ingredients and promised effects is difficult for consumers to overlook, let alone review. Several thousand preparations fill the shelves in pharmacies, drugstores, supermarkets and health food stores, while the Internet also offers a lot that is not available in Germany. The capsules, tablets or drops look like medicines. Legally, dietary supplements (NEMs) are food, they do not have to go through an authorization process. Manufacturers do not need to prove efficacy through trials, nor are they looking to see if what they are selling has any side effects. The buyer can therefore not be sure whether it is a "meaningful or valuable food", the Federal Institute for Risk Assessment (BfR) emphasizes: "Dietary supplements can be offered on the market, even if their nutritional value is questionable."
Why should we supplement our food at all?
"13 vitamins, 15 minerals, eight amino acids and various fatty acids must be supplied with food for life, plus a few thousand phytonutrients, which take over important functions in the metabolism," says Professor Karlheinz Schmidt, physician and chemist at the University of Tübingen. To be sufficiently supplied with all these vital substances, a healthy and balanced diet is necessary. However, this is often not possible in our modern everyday life, proponents of dietary supplements must consider. In ready meals, fast foods and diets, the body does not get everything it needs. Due to long storage and the high degree of processing of food, vital substances could also be lost. It is often claimed that the soil is so drained that today's food contains less vitamins and minerals. This could not be confirmed by a study of the German Society for Nutrition (DGE), in which data from the years 1954 to 2000 were compared.
Can pills replace a healthy diet?
Five portions of fruits and vegetables daily recommended by the DGE. It also includes whole grains, low fat milk and dairy products, low meat and sausage, at least once a week saltwater fish and a sufficient amount of liquid for a healthy mixed diet. This can not be replaced by a few capsules or tablets. Anyone who is permanently on one side and unbalanced diet, this can not offset by the intake of supplements, say the consumer advocates of the BfR. Nutritionist Professor Hans Konrad Biesalski from the University of Hohenheim confirms this: "We repeatedly find out: You can not reduce foods such as tomatoes or apples to two or three ingredients." In fact, all types of fruits and vegetables, such as carrots, peppers, kohlrabi, oranges, cherries and pineapples, contain innumerable substances, many of which you do not even know what they do - also in interaction with each other. Therefore, the DGE also advises of extracts, for example from grapes or garlic in capsule form. Because: "Only when consumed directly, the whole spectrum of essential and bioactive substances is really taken in. This is especially true for the fiber."
For whom can nutritional supplements still be useful?
In addition to pregnant women and lactating women, these are primarily people with chronic diseases such as intestinal, kidney, liver or cancer, which affect the absorption of nutrients (eg iron in the case of changes in the gastrointestinal tract).Elderly people who have food problems or are bedridden also need supplementary resources. For certain diseases, the need for individual nutrients is also so high that it is difficult to cover with food alone. Patients should discuss with their doctor what makes sense in addition. This also applies to those who take medication frequently or regularly.
It can be difficult to nourish enough calcium to prevent osteoporosis. If you can not take the necessary 1000 to 1200 milligrams of this mineral daily (you can check this with the calcium calculator), you can take supplements (maximum 500 milligrams per day). However, if the stomach is too low in acidity, due to age, or because acid blockers are being swallowed simultaneously for heartburn, the body can not absorb the calcium carbonate from these remedies. In these cases, calcium gluconate is better utilized. In order that the calcium is not immediately excreted again with the urine, also sufficient potassium is needed.
According to the National Consumption Study, many women and men in Germany are poorly supplied with folic acid and vitamin D. Whether it makes sense to supplement these substances has not been proven. To prevent iodine deficiency, however, experts recommend all to use iodized salt. The favorite supplement of the Germans, the vitamin C, does not bring much: Studies show that it does not prevent colds. It may shorten the duration of the illness by just under half a day.
In which diseases are dietary supplements useful?
Some diseases have different recommendations than healthy people. For example, cardiological societies advise patients with coronary heart disease who have elevated levels of certain blood lipids (so-called triglycerides) to be treated with omega-3 fatty acid-containing fish oil capsules approved as medicinal products - but only under medical supervision. Even with rheumatism, osteoporosis, macular degeneration and cancer, nutrients can be prescribed as additional therapy by the doctor - but often in the form of drugs with a higher dosage than it is included in dietary supplements.
Can vitamin supplements prevent diseases?
That is questionable. The development of cardiovascular diseases and cancer should involve free oxygen radicals. Antioxidants such as vitamins C and E, which neutralize radicals, have therefore been attributed preventative potential. Now, however, it has been proven that the two vitamins may do more harm than good. New research suggests that our body needs free radicals, such as those found in sports, to practice in an emergency. "It can be imagined as a vaccine," says Professor Regina Brigelius-Flohé of the German Institute for Nutrition Research (DIFE) in Potsdam. "Small amounts of reactive oxygen species make the body better prepared for larger volumes." Antioxidants prevent this.
This may explain why taking beta-carotene, vitamin A and vitamin E preparations may shorten life expectancy, according to studies. A vitamin-rich diet containing these substances in a tolerated dose and in combination with other substances does not.
And what about cancer?
So far, studies have shown no evidence that dietary supplements prevent the development of tumors. The supposition that beta carotene could protect smokers from lung cancer was not confirmed. Also, multivitamin supplements, vitamin C and folic acid proved to be ineffective, vitamin E may increase the lung cancer risk. People who take a lot of folic acid or folate with their diet are less likely to develop colorectal cancer, but the intake of synthetic folic acid seems more likely to promote the growth of tumors in the gut. The benefit or harm of a vitamin may depend on the dose or whether cells are already degenerate in the body. At any rate, the World Cancer Research Foundation does not recommend dietary supplements for cancer prevention.
What can indicate a lack of vital substances?
Fatigue, nervousness, lack of concentration, irritability, increased susceptibility to infections, hair loss and disorders in the gastrointestinal tract may indicate a shortage of certain vital substances. Whether this is actually the cause of the complaints, but only a doctor can judge.
Can dietary supplements have side effects?
Absolutely. On the one hand, vitamins and minerals can be overdosed. On the other hand, they are not always harmless otherwise. In the US, researchers have discovered that diabetics have a higher selenium level in the blood than other people. They therefore recommend that Americans should not take supplements that contain selenium. In general, experts recommend that you keep to the recommended maximum daily intake when taking supplements. The balance should also include foods enriched with vitamins and minerals.With individual substances, preparations often contain a multiple of the daily requirement. In addition, the Federal Institute for Risk Assessment (BfR) warns of possible interactions with drugs. Therefore, the doctor should be informed about an intake.
Does one have to fear for his health if one does not eat five portions of fruit and vegetables daily?
The average German reaches or even surpasses the DGE reference levels for most vitamins. If this does not always succeed, that is no reason to panic. The values are set so high that there is a safety margin. Those who take less of a vitamin or mineral are not automatically underserved. Fixing on individual substances does not bring much anyway, as research shows. And the five-day rule? Nutritionist Hans Konrad Biesalski sees this less closely: "This is in principle a good approach, but three or four servings of fruits and vegetables per day do it too.The best one varies in selection and preparation, consumes vegetables, for example, sometimes raw, sometimes cooked, sometimes as juice. " Ultimately, it makes the right mix of different substances. And no chemist can make it as precisely as nature does.
