How much zinc does your body need?
Zinc is one of the most important essential trace elements. It is involved in numerous metabolic processes and is important for the immune system. Even a minimal undersupply of zinc brings the zinc balance out of equilibrium, so that some metabolic processes cannot take place at all or not correctly. What must be considered in the diet to cover the daily requirement of zinc? In which cases is a zinc supply via food supplements useful? And do vegetarians and vegans have a higher risk of suffering from zinc deficiency?
Reference values of the German Society for Nutrition e. V.
Zinc is an essential trace element, the body cannot produce it itself and cannot store it for long. It must therefore be actively ingested daily through food. Although there are only 2-4 grams of zinc in the body, it is nevertheless indispensable for our health: as a co-enzyme, zinc ensures the function of up to 300 enzymes in the body and is involved in numerous metabolic processes. Only when the body is optimally supplied with zinc does the metabolism of many organs and functions of the body remain intact.
The German Nutrition Society (DGE), together with the nutrition societies of Austria and Switzerland, publishes reference values for nutrient intake. These D-A-CH reference values exist for all nutrients and are continuously updated. Until summer 2019, the DGE recommended a daily intake of 7 mg (women) and 10 mg (men) of zinc. In July 2019, the D-A-CH reference values were updated by taking into account the level of daily phytate intake. There are now three different recommendations for adults. Recommended zinc intake in mg per day for adults aged 19 and over depending on phytate intake according to DGE
| Männer | niedrig | mittel | hoch |
|---|---|---|---|
| Phytatzufuhr mg/Tag |
11 | 14 | 16 |
| Frauen | niedrig | mittel | hoch |
|---|---|---|---|
| Phytatzufuhr mg/Tag |
7 | 8 | 10 |
Zinc supply
The human body cannot produce zinc itself and can only store it for a short time, so it must be supplied with the necessary dose daily for optimal supply. With a healthy diet, sufficient zinc is absorbed through food; optionally, zinc can be supplied through dietary supplements.
Food
Many foods contain the trace element zinc, whereby in principle the zinc from animal products is better utilisable than that from plant products. The following table contains a selection of plant and animal foods with a high zinc content.
| Tierische Lebensmittel | Zinkgehalt mg/100g |
|---|---|
| Austern (Durchschnitt) | 86 |
| Leber | 6 |
| Lamm | 5 |
| Salami | 4 |
| Rindfleisch | 3 |
| Käse | 4 |
| Krabben | 2,3 |
| Plant foods | Zinc content mg/100g |
|---|---|
| Soybean meal | 5.7 |
| Rolled oats | 4.5 |
| Wholemeal rye flour | 3,9 |
| Mais | 3,5 |
| Nüsse (Durchschnitt) | 3,0 |
| Nudeln | 3,1 |
| Zartbitterschokolade | 2,1 |
Oysters have by far the highest zinc content: depending on the type and preparation, they can contain up to 160 mg zinc per 100 g. But a healthy mix of meat, fish, dairy products, wholemeal products, pulses and nuts can also cover the daily zinc requirement. It is important to soak legumes and cereals before eating them or to let them sprout so that the phytic acid is broken down. The same applies to wholemeal bread, where the phytic acid is broken down by traditional doughing with yeast, baking ferment or sourdough.
Vegans and vegetarians
Vegetarians and vegans also do not have to fear a zinc deficiency if they treat legumes and cereal products appropriately before consumption and thus increase the bioavailability of the zinc. Their diet usually includes high-quality ingredients that are rich in vital nutrients and, when prepared appropriately, provide sufficient zinc. In fact, a diet consisting predominantly of convenience foods and isolated carbohydrates, such as those found in white flour, starch or polished rice, and too many dairy products carries a higher risk of zinc deficiency.
These food components improve zinc absorption:
- Vitamin C
- Hydrocarboxylic acids such as citric acid, malic acid and tartaric acid from various fruits
- Amino acids such as histidine, methionine, glutamine and cysteine from meat and cereals
These food components hinder the absorption of zinc:
- Phytates (phytic acid)
- Oxalic acid, e.g. in rhubarb, spinach, chard
- Casein in dairy products
- Iron from food supplements
- Heavy metal cadmium
Food supplement
In some situations in life, the body has an increased zinc requirement, e.g. during pregnancy and breastfeeding or for competitive athletes. But older people also often have an increased need. In order to cover the increased zinc requirement, the administration of a zinc preparation can be advisable as a temporary cure or permanent support. They are offered by numerous manufacturers in various forms, e.g. as tablets or capsules. The choice of product and the dosage should always be discussed with your doctor.
Zinc deficiency
Zinc deficiency is particularly noticeable in skin and mucous membrane problems and in a weak immune system. Acne, diarrhoea, taste disorders, fatigue and listlessness, increased susceptibility to infections, wound healing disorders, hair loss, fertility disorders in men and women, or even growth or development disorders in children are only some of the possible symptoms that can indicate a zinc deficiency. However, since many of these symptoms cannot be clearly attributed to a zinc deficiency, a short-term zinc cure is often prescribed. If the symptoms diminish or even disappear completely, there was a zinc deficiency that could be remedied by the increased zinc intake.
Overdose
Not only zinc deficiency can make you sick, overdose can also be harmful. An intake of ten times the daily dose, i.e. approx. 100 mg, can cause nausea, diarrhoea and vomiting. With a moderate zinc intake of up to 25 mg per day over a longer period of time, interactions with copper and iron can occur with the consequences of anaemia. Therefore, zinc is often taken as a course of treatment over a limited period of time.
The European Food Safety Authority (EFSA) has set a total daily tolerable intake of 25 mg of zinc for adults and 7-22 mg of zinc for children, depending on body weight. The tolerable total intake should not be exceeded permanently.
For food supplements, the Federal Institute for Risk Assessment (BfR) recommends a maximum zinc content of 6.5 mg per daily dose. In Germany, over-the-counter preparations contain between 5 and 25 mg of zinc per tablet. However, foreign high-dose zinc preparations containing 50-100 mg of zinc per tablet are also available on the internet. The good news is that zinc overdose is unlikely to occur through normal dietary intake. When taking food supplements, follow the dosage instructions. Oral hygiene products such as toothpaste, mouthwash or adhesive creams can also contain high concentrations of zinc.
For the treatment of zinc deficiency, zinc supplementation with 10 to 25 milligrams per day is sufficient. Higher doses are usually not necessary and may even be harmful with prolonged use. The tolerable upper intake level, also known as „tolerable upperintakelevel(UL)“, is 25 milligrams per day. At this dosage, no side effects are expected, even with long-term intake. This amount corresponds to the total daily intake of zinc, i.e. from food and additional zinc supplementation.
In order to absorb zinc, the body must be given zinc-containing food or zinc supplements. Since the mineral is absorbed through the intestines, a healthy intestine is a prerequisite for good absorption. Vitamin C, hydrocarbons such as citric or malic acid, and various amino acids from meat and cereals promote zinc absorption.
Healthy, strong hair needs zinc. It is involved in the formation of keratin and collagen. The stable protein fibre keratin is the basic building material of hair, while the protein collagen ensures that the hair is firmly anchored in the scalp. Zinc promotes healthy hair growth and a healthy scalp. It also strengthens the immune system and protects against inflammation at the hair root.
A varied and wholesome diet provides a healthy person with sufficient zinc. Some people have an increased risk of zinc deficiency due to their age, lifestyle or illness, and supplementation can be useful here. Risk groups include, for example, growing children, pregnant and breastfeeding women, senior citizens, people with chronic bowel disease, diabetes or rheumatism, bowel, liver or kidney disease or cancer patients undergoing chemotherapy or radiotherapy.
Children also need zinc, because the trace element is necessary for growth and the healthy development and maturation of the brain. However, the intake levels recommended by the German Nutrition Society (DGE) for children up to 15 years of age are achieved with a balanced diet, so that additional zinc supplementation is not necessary. The exception is a proven zinc deficiency, which is treated with zinc supplements. Children should refrain from taking zinc as a preventive measure to strengthen the immune system and prevent colds, as there is a risk of a harmful overdose.
Vitamin B refers to a group of vitamins that are important for healthy hair and scalp. The important B vitamins include vitamin B3 (niacin), B5 (pantothenic acid), B6 (pyridoxine), B7 (biotin) and folate. If too few B vitamins are taken in over a long period of time, the hair can become brittle and fall out.
Constant scratching of the dog can indicate a food intolerance or an allergy. On the one hand, it is important to find out what the animal is reacting to: a so-called elimination diet is used to systematically exclude possible causes until the trigger is found. On the other hand, the animal should be supplied with the nutrients zinc, biotin and essential fatty acids, which have a positive effect on the skin metabolism.
Conclusion
With a balanced diet, the zinc requirement can be covered through food. In special life situations such as pregnancy and breastfeeding or as a competitive athlete, as well as when zinc deficiency symptoms occur, a zinc preparation can be taken for a certain period of time after consultation with the doctor. Vegans and vegetarians do not have to fear a zinc deficiency if whole grain products and legumes are treated accordingly before consumption.
