Vitamins, minerals and amino acids · Blood

Zinc

The zinc in your blood; a deficiency is rare in the Netherlands and the blood value says little about the stores in your body.

At a glance

Measured in blood
In 4 test panels
Check the preparation

Explanation

Zinc: what is measured?

Zinc is a trace element: a mineral the body needs only a little of. It is part of many enzymes and is needed for building proteins, growth, wound healing and the immune system. Almost all zinc is in the cells; only a very small part is in the blood, where it is mostly bound to the protein albumin. This analysis measures the zinc in the blood.

What can it detect?

A severe zinc deficiency, for example with bowel diseases causing poor absorption (Crohn's disease, celiac disease, after bowel surgery) or long-term artificial feeding
Too much zinc from long-term high-dose supplements, which can cause a copper deficiency

Result

What does the result mean?

Zinc too high

A raised zinc is caused almost only by supplements; according to the Netherlands Nutrition Centre (Voedingscentrum), it is virtually impossible to get too much zinc from food. For adults, a tolerable upper limit of 25 milligrams per day applies. Anyone who takes a high dose of zinc tablets every day for a long time can develop a copper deficiency, eventually with anemia. A falsely raised value can be caused by damaged blood cells (hemolysis) or by zinc from the skin or the collection materials, especially with a finger prick.

Zinc too low

A slightly low zinc is common without there being a true deficiency. The value drops temporarily with inflammation or infection, is lower later in the day and after a meal, and is lower with a low albumin and during pregnancy. A true deficiency is rare in the Netherlands and is seen mainly with bowel diseases causing poor absorption, malnutrition or a long-term fully plant-based diet without good sources of zinc. Symptoms of a deficiency are not very specific: more frequent infections, slow wound healing, less appetite, skin changes and changes in smell or taste.

After an abnormal result

With a low zinc, the GP checks whether there was inflammation or infection and repeats the measurement in the morning if needed, together with CRP and albumin. With a clear and persistent deficiency, the GP looks for a cause, such as a bowel disease. With a raised zinc, supplement use is checked and copper is sometimes measured.

Reliability

How reliable is the test?

Zinc in the blood is an insensitive measure of the body's zinc stores: the body keeps the blood value stable for a long time, and inflammation, time of day and meals often change the value more than a mild deficiency does. According to the Health Council of the Netherlands, the signs of a zinc deficiency are not specific and it is difficult to link a deficiency to symptoms. In people without symptoms, a single value therefore says little.

What can affect the result?

Inflammation or infection lowers the value temporarily, even without a deficiency.
The time of the blood draw and a meal beforehand affect the result; a morning blood draw on an empty stomach gives the most comparable value.
Hemolysis and contamination with zinc from the skin or materials, especially with a finger prick, can falsely raise the value.
Zinc supplements raise the value; reference values differ per laboratory.

Preparation

Preferably do not eat for 8 hours before the sample is taken and drink only water. Zinc in your blood drops after a meal.
Preferably have your blood taken in the morning, because zinc in your blood drops during the day.

Who it is for

Who is the test useful for?

Useful for

Useful when a severe deficiency is suspected, for example with bowel diseases causing poor absorption, after bowel surgery or with malnutrition, and with long-term use of high doses of zinc supplements. With a vegetarian or vegan diet, zinc intake can be lower, but the blood value does not reliably show a mild deficiency. In healthy people without symptoms, a deficiency is rare and the result says little.

How common is it?

How often a zinc deficiency occurs in the Netherlands is not well known; according to the Netherlands Nutrition Centre (Voedingscentrum), signs of a deficiency are, as far as is known, rare. The Health Council of the Netherlands considers the zinc intake of the average Dutch population adequate. In model calculations in which all meat and dairy were replaced by plant-based products, zinc intake did fall below the recommendation.

Netherlands Nutrition Centre (Voedingscentrum) and Health Council of the Netherlands (2023)

Drawbacks and risks

A slightly low value due to inflammation or the time of the blood draw is easily read as a deficiency; this can lead to unnecessary use of zinc supplements, which cause a copper deficiency at long-term high doses.

Get tested

Zinc: test panels

Zinc is part of these test panels. You order online and have your blood drawn at a collection point or collect the sample at home.

Blood draw
Zinc
Zinc in serum; immune system and wound healing.
€ 32,00
Fingerstick
Zinc
Zinc in serum; immune system and wound healing.
€ 32,00
Blood draw
Vegetarian Extensive
Iron, ferritin, B12 total and active, vitamin D, folic acid, zinc, magnesium, hemoglobin, and hematocrit. Complete nutritional status check.
€ 269,00
Fingerstick
Micronutrients
Measures essential minerals and trace elements via finger prick. Analysis of 7 micronutrients.
€ 248,00

How reliable is the test?

Zinc