Do you tend to have brittle nails, weak hair and cracked skin or are you more susceptible to infections? These can all be signs of a zinc deficiency. Zinc is involved in many processes in our body and is associated with a number of different symptoms when deficient.
If you suspect you have a zinc deficiency or are not sure what your zinc levels are, a zinc deficiency self-test can give you more clarity.
Our zinc deficiency test 2022 presents the most popular test kits and contains all the important information about self-tests with which you can determine whether you actually have a zinc deficiency.
- 1 Weekly newsletter with the best personal finance tips
- 2 The most important facts
- 3 The Best Zinc Deficiency Test Kit: Our Picks
- 4 Guide: Questions you should ask yourself before buying a zinc deficiency test
- 4.1 What role does zinc play in the human body?
- 4.2 What is the daily requirement of zinc?
- 4.3 What foods contain zinc?
- 4.4 Does zinc help with colds?
- 4.5 What are the causes of zinc deficiency?
- 4.6 What are the consequences of a zinc deficiency?
- 4.7 What types of zinc deficiency self-tests are available?
- 4.8 Where does a zinc deficiency test kit cost?
- 4.9 How can I treat a zinc deficiency?
- 4.10 Do zinc supplements interact with other medicines?
- 4.11 Should I take a zinc preparation together with biotin?
- 4.12 What happens in the case of a zinc overdose?
- 5 Measure zinc levels in your blood yourself: What to look for in zinc self-tests
The most important facts
- Zinc is an important trace element that is involved in many processes in the body. In particular, a deficiency of zinc can lead to a weakened immune system, delay wound healing, worsen existing skin problems such as acne or atopic dermatitis, and have an impact on the appearance of hair and nails.
- You can check your zinc deficiency with simple self-tests from home and have it measured in the lab. The mineral blood test is the most common. In many cases, you can get tested not only for zinc, but for other minerals like magnesium or selenium.
- The results of a blood test should be taken with care. In addition to the test result, you should question your lifestyle habits (e.g. alcohol consumption, fast food) and check yourself for possible signs of zinc deficiency.
The Best Zinc Deficiency Test Kit: Our Picks
Guide: Questions you should ask yourself before buying a zinc deficiency test
In order to inform you comprehensively about a zinc def iciency self-test and to give you an understanding of the current state of science on zinc deficiency, we have summarised all the important information for you in the following sections.
What role does zinc play in the human body?
For example, zinc promotes the formation of testosterone (11) and of new cells when body cells are damaged. Zinc also helps the pancreas to produce insulin, which lowers blood sugar levels. Furthermore, zinc helps to limit the harmful effects of heavy metals such as lead in the body, preventing damage to nerve cells in particular.
Zinc ointments enriched with zinc oxide can help with sunburn by renewing damaged skin cells.
Zinc is also used for various purposes in dermatology (skin medicine). For example, zinc can be helpful in the treatment of acne (9), basal cell carcinoma and warts. In acne, zinc can reduce oil production in the skin and thus prevent bacterial infections. In sun creams, zinc is used as an additional sunscreen. In anti-dandruff shampoos, zinc is used to suppress the formation of dandruff.
Zinc makes enzymes that help break down alcohol in the body. Without zinc, you would have alcohol poisoning after just one glass of beer.
But zinc is also important for our eyesight. This trace element transports vitamin A from the liver to the retina of the eye. Vitamin A, in turn, is crucial for our eyes to be able to perceive light. Without vitamin A, we would not be able to see. It is also assumed that there is a connection between zinc and the sense of smell.
Because we cannot produce zinc in our bodies, we have to get zinc from food every day.
What is the daily requirement of zinc?
On the one hand, the unborn child must also be supplied. On the other hand, a strong urge to urinate during pregnancy can cause the pregnant woman to lose a lot of zinc. Breastfeeding women need 12 milligrams of zinc daily because the child also absorbs zinc through breast milk (4, 22).
We have summarised the recommended daily amount of zinc for you here:
|Group||Recommended daily amount of zinc|
|Pregnant women||11 milligrams|
|Breastfeeding women||12 milligrams|
The daily requirement of zinc ranges between 8 and 12 milligrams and depends on gender and circumstances. Pregnant and breastfeeding women have an increased need for zinc.
What foods contain zinc?
|Animal foods||plant foods||amount of zinc in milligrams per 100 grams|
|Oysters||wheat germ, wheat bran||10 to 25 milligrams|
|Edam, Emmental, chicken egg, beef||Sunflower seeds, linseed, soya flour||5 to 10 milligrams|
|Tilsiter, Gouda, Parmesan||rye, wheat, peas, lentils, walnuts||2.5 to 5 milligrams|
Note, however, that the small intestine cannot absorb zinc completely from food.
So if 100 grams of beef and 100 grams of flaxseed contain the same amount of zinc, your body can absorb more zinc from beef than from flaxseed.
Did you know that oysters contain a lot of zinc?
Oysters are good sources of zinc and contain almost 19 times as much zinc as oatmeal.
In addition, some foods contain nutrients that make it easier or more difficult for the body to absorb zinc. We will explain what these are in the next section.
Anti-nutrients in foods
The reason why zinc from plant foods is usually less easily absorbed by the body than from animal products is that nuts, legumes and grains contain many anti-nutrients that prevent optimal absorption of zinc through the intestines (20). But animal products can also have such anti-nutrients.
These anti-nutrients include:
- Phytate in whole grains except sourdough bread (14)
- Oxalate in beetroot, rhubarb and spinach
- Tannins in wine, green and black tea
- Phosphate in cola, fish and meat
- Histidine in dairy products
To reduce the amount of phytate in whole grains, you can soak the grain for several hours before preparing it.
Nutrients that promote zinc absorption
Conversely, there are nutrients in certain foods that support the absorption of zinc in the body. These include, in particular, animal protein (14, 16).
These nutrients promote the absorption of zinc:
- Histidine and cysteine in almonds, peanuts, beef and pork (14)
- Methionine in almonds, cottage cheese, cod, mackerel and tuna fish (14)
- Citric acid in apples, berries, pears and citrus fruits (14)
In the case of histidine, you can see that the same nutrient can promote or hinder the absorption of zinc, depending on the foods in which it is present.
Does zinc help with colds?
The German Nutrition Society recommends taking zinc supplements for colds only if there is a proven zinc deficiency (18).
In contrast, the Cochrane Collaboration published a study in 2015 according to which the duration of the common cold was shortened by one day if the participants took 75 milligrams of zinc daily. However, this effect only occurred if the zinc supplement was taken within 24 hours of the onset of the first signs of a cold (6, 17).
What are the causes of zinc deficiency?
On the other hand, there are population groups that are more affected by a zinc deficiency than others. These include diabetics, among others. High blood sugar levels go hand in hand with more frequent urination, so that diabetics excrete more zinc through their urine (21).
These groups can be particularly affected by a zinc deficiency:
- Vegetarians and vegans (20)
- Diabetics (21)
- Elderly people
- Pregnant and breastfeeding women
- People suffering from permanent stress
- People with chronic inflammatory bowel diseases (2)
Finally, your diet also plays an important role. Some foods contain anti-nutrients that limit the absorption of zinc through the intestines (5). These include phosphate in cola and meat or tannins in wine, green and black tea.
The small intestine absorbs zinc from plant food sources more poorly than from animal food sources (20).
People with inflammatory bowel disease, such as Crohn's disease or ulcerative colitis, may also be deficient in zinc due to impaired absorption of nutrients in the intestine (2). Pregnant and breastfeeding women also have an increased need for zinc.
What are the consequences of a zinc deficiency?
The most common possible consequences of a zinc deficiency include:
- Hair loss (1)
- Brittle nails
- Diarrhoea (1, 16)
- Slow wound healing (1, 2)
- Night blindness and reduced sense of smell
- Fatigue and depressive moods
- Increased susceptibility to infections (1)
- High weight loss (1)
- Muscle cramps
- Erectile dysfunction
The effects of a zinc deficiency are particularly evident in the immune system, the condition of nails and hair, and in problems with the skin. We will discuss these areas in more detail here.
Effects on the immune system
A lack of zinc in the body can weaken the immune system. For example, your immune system may be weakened if you have frequent, often severe and prolonged sore throats, colds and coughs. Another sign can be the frequent occurrence of herpes, especially on the lips, where the painful blisters appear regularly.
Susceptibility to infections can also increase due to a zinc deficiency, especially in relation to the respiratory tract, mucous membranes and gastrointestinal tract. Repeated suffering from bronchitis, bladder infections or gastrointestinal infections can be the result.
Effects on the skin
Recurrent problems with the hand may also be due to a zinc deficiency. The skin appears cracked, dry and scaly. In some cases, redness, inflamed areas and pustules develop (10).
If you have acne, psoriasis or atopic dermatitis, the acute flare-ups may recur. Wounds may heal more slowly or the healing process may be delayed. In addition, the risk of bacterial infections is increased.
Effects on hair and nails
A prolonged deficiency of zinc can manifest itself in growth disorders of nails and hair. Hair can appear weak and thin and is more prone to split ends and breakage. Sometimes there is hair loss and premature greying.
Zinc deficiency also affects the appearance of the nails.
The nails can become brittle and split, show conspicuous white spots or severe furrows and grooves, and be thin.
Because the signs of a zinc deficiency can be so varied, it can make sense to get tested for a zinc deficiency. There are several self-tests on the market that you can use to check for a deficiency.
What types of zinc deficiency self-tests are available?
- Blood test
- Hair test
- Urine test
With a test kit, you don't need to book an appointment with a doctor and you may avoid long waiting times. In many cases, you will get your test result in a few days. In the following section, we will go into more detail about the different types of zinc deficiency self-tests.
Many manufacturers offer a blood test kit that you can use to test for zinc deficiency. In many cases, such blood tests can not only determine your zinc level, but also examine the blood concentration of other minerals such as magnesium or selenium. All it takes is a small prick in your finger with a lancet. The few drops of blood are poured into a sample tube.
In the next step, you create a user account with most providers on their website or app. Here you can retrieve your test ID and your results after you have sent the sample tube to the relevant laboratory, where your sample will be analysed.
As soon as the result is known, you will receive a result report. This report will not only tell you whether you have a zinc deficiency, but will also usually contain recommendations on how to keep your blood zinc levels optimal.
However, remember that 98 per cent of zinc is stored in body cells such as muscles and bones, and the remaining 2 per cent is in the blood. If there is a lack of zinc in the blood, the mineral is supplied from the body's cell stores to balance the zinc concentration in the blood.
So it is possible that the test will show you a normal zinc level, but you could suffer from a zinc deficiency in the longer term when the zinc reserves from the body's cells are depleted.
There are also test kits that can determine your zinc levels through hair analysis. This is ideal for those who want to avoid a blood test or are not allowed to have a blood test because of conditions such as HIV or hepatitis. This method also seems to be good for determining the supply of zinc in children who do not eat enough.
A hair test provides values for several vitamins, amino acids and trace elements.
The hair analysis usually determines not only the zinc value, but also the content of certain vitamins, enzymes, amino acids and other trace elements in the body.
So you can be tested for vitamin A, calcium, magnesium or iron at the same time. With some hair tests you can also check your heavy metal levels. Heavy metals such as mercury or lead can be harmful to your health.
Any type of body hair can be tested. The instructions for the test explain how many hairs should be cut off. Brushed-out hairs cannot usually be used. Hair that has been dyed or treated in any other way has no influence on the test result. Based on the hair analysis, further therapeutic steps can then be developed.
A zinc deficiency can also be detected by means of a urine test. The concentration of haemopyrrol in the urine is determined. Haemopyrrol can be detected in the urine of patients with the genetic metabolic disorder pyrroluria.
Normally, pyrroles are contained in bile pigments that are excreted in the stool. In the case of pyrroluria, however, there are more pyrroles in the body. These excess pyrroles leave the body as a complex compound together with zinc and vitamin B6 via the urine. This can lead to a higher excretion of zinc and vitamin B6 from the body.
You send your urine sample to the laboratory, where it is analysed. One advantage of this test method is that it can also measure your vitamin B6 content. However, the urine method only gives reliable results if you have certain metabolic disorders like pyrroluria.
Where does a zinc deficiency test kit cost?
|HPU urine test||approx. 30 euros|
|Hair analysis||approx. 39-159 euros|
|Blood test||approx. 69 euros|
The cheapest is the HPU urine test. It examines the lack of zinc and vitamin B6 in the presence of the metabolic disorder pyrroluria. The costs for a hair analysis can vary considerably. This usually has to do with which micronutrients are tested for in the analysis.
Some hair tests not only measure the levels of vitamins, enzymes and trace elements in the body, but also examine how high the exposure to heavy metals such as lead or mercury is. Such tests are somewhat more expensive.
How can I treat a zinc deficiency?
Nasal sprays containing zinc are not recommended because they can impair your sense of smell.
If you prefer to avoid animal products, zinc supplements can help. These preparations are available in different forms. You can take zinc in the form of effervescent tablets or lozenges, capsules, powder or drops, or apply it as an ointment.
It is not the form, but the zinc compound of the preparation that is important. The preparation should combine zinc with other substances that contribute to an improved absorption of zinc.
Most preparations contain one of the following zinc compounds:
- Zinc histidine (the only compound without known side effects) (15)
- Zinc bisglycinate (23)
- Zinc picolinate (12)
- Zinc gluconate (12, 13)
- Zinc sulphate (only effective on an empty stomach) (13)
There are many aspects you should consider when taking zinc supplements. For example, there may be interactions with other medications, or you may overdose on zinc and have negative health consequences (5) if you do not have a zinc deficiency.
Do zinc supplements interact with other medicines?
Therefore, you should take a zinc supplement a few hours before or after taking the above-mentioned medicines.
In any case, if you are taking zinc supplements at the same time as medicines or other minerals in high doses, you should check with your doctor beforehand.
Should I take a zinc preparation together with biotin?
It can make sense to take zinc and biotin at the same time.
Biotin is found in foods such as mushrooms, meat and whole grain products.
Note, however, that minerals cannot be utilised by your body in any quantity. If you take several different preparations, they may interact with each other in the opposite way and lead to deficiency symptoms. For example, taking large amounts of iron and zinc at the same time can lead to your body not absorbing any more iron for a long time.
What happens in the case of a zinc overdose?
However, the safe upper limit of 25 milligrams of zinc per day may be exceeded, for example, by taking zinc supplements, and this can harm the body.
If you have not been diagnosed with a zinc deficiency, you should not take supplementary zinc supplements, as there is a risk of overdosing (5). In contrast, it is very rare that too much zinc is taken in through the diet.
The possible consequences of a zinc overdose include:
- Gastrointestinal complaints (7)
- Diarrhoea and vomiting (3, 7)
- Kidney dysfunction
- Hair loss
- Anaemia (anaemia) (1)
- Numbness and weakness in the limbs
- Bone loss
If you take between 225 and 450 milligrams of zinc, you may experience severe vomiting. If you take too much zinc over a long period of time, this can also lead to an iron deficiency (1). Because of the high zinc content, the body can no longer absorb iron, which prevents the blood platelets from forming properly. The result is anaemia (1).
Similarly, excess zinc has negative effects on the levels of copper (5, 7), calcium and magnesium in the body. Too much zinc can lead to a deficiency of copper and thus to numbness and weakness in the limbs.
In addition, too much zinc can cause long-term deficiencies in calcium and magnesium, increasing the risk of bone loss, poor performance and faulty transmission of stimuli.
An overdose of zinc also reduces the HDL cholesterol present in the body. This 'healthy' cholesterol variant removes the LDL cholesterol responsible for hardening of the arteries and repairs damage that occurs to cell membranes (7).
Measure zinc levels in your blood yourself: What to look for in zinc self-tests
In this section, we have summarised the most important aspects you should consider when taking a zinc deficiency self-test if you decide to do a blood test at home.
How does a blood test work?
A self-test to measure your blood zinc level is usually quick and easy. You take a small sample of blood from your fingertip using a lancet. You put this blood sample into a tube and send it in a return envelope to the specified diagnostic laboratory.
You will then receive a detailed report of your results and, if necessary, suggestions for optimising the zinc concentration in your blood.
Many manufacturers offer test kits that allow you to be tested for several minerals at once, for example zinc, magnesium and selenium.
How reliable is a blood test?
The human body usually contains 2 to 3 grams of zinc (5). 98 percent of this amount is stored in the body's cells, mostly in the muscles and bones. Only 2 percent of the zinc is therefore in the blood.
When the concentration of zinc in the blood drops, the body replenishes the stored supply from the body's cells to restore the optimal level of zinc in the blood.
A zinc deficiency is only reflected in blood levels when it is already advanced.
For this reason, you should take a critical look at your blood test result (2). Your zinc level in the blood may well be within the normal range, if the zinc is simultaneously dwindling in the body's cells.
A better diagnosis of zinc deficiency is possible by means of hair analysis. In a 2016 study by Han et al. of children suffering from malnutrition and delayed growth, hair analysis diagnosed zinc deficiency in 88 per cent of cases. In the blood test, it was only 55 per cent (19).
Therefore, you should always interpret your test result in the light of whether you feel any effects of zinc deficiency on the body and what kind of lifestyle you lead (2).
Who is the blood test not suitable for?
There are certain groups of people for whom a blood test is not suitable or who are not allowed to take the test because of the high risk of infection for the laboratory technicians who evaluate the results.
These groups include above all:
- People with infectious diseases like HIV and hepatitis
- People with a blood clotting disorder (haemophilia)
- Pregnant and breastfeeding women
- Children under 18
Pregnant and breastfeeding women are advised to perform a zinc deficiency only under medical supervision, because the recommendations and reference values of the self-test do not apply to these groups of people. Instead, pregnant and breastfeeding women should contact their doctor to discuss their test result.
In addition, the self-test is not suitable for detecting diseases. So if you are suffering from severe pain or depression, you should see a doctor.
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