Zinc – The Immune Booster

Zinc is one of the vital nutrients we very often lack. One reason is that our body uses up its zinc stores quite quickly — above all when we are ill. Another is that the soil is now very poor in zinc, so we take in considerably less of it through food than we used to.

Zinc is an essential trace element that fulfils numerous important functions in our body. It plays a decisive part in how the immune system works, by supporting the production and activity of white blood cells and so strengthening our defences against infection. We need zinc for cell division and cell growth, which supports wound healing and tissue repair.

The synthesis of DNA and proteins, needed for the growth and repair of tissue, would not be possible without zinc either. Zinc is moreover a cofactor for over 300 enzymes involved in important biochemical processes, such as the metabolism of carbohydrates, fats and proteins.

Zinc also has a strong antioxidant effect and so helps protect the cells against oxidative stress, working as part of antioxidant enzymes such as superoxide dismutase (SOD). Beyond that, zinc plays a part in regulating various hormones, including insulin, testosterone and thyroid hormones. It also protects every gland that makes hormones, supports the pancreas and the adrenal glands and helps to stabilise the glucose level in the blood.

Because zinc is involved in how the taste and smell receptors work, our sense of taste and smell would be impaired without this important trace element. Zinc plays an important part in our reproductive health too, particularly in producing sperm and in the development of the foetus during pregnancy.

We need zinc for our skin health as well. It supports the health of the skin and can help in treating skin conditions such as acne and eczema. Zinc contributes to brain function, plays a part in passing signals between nerve cells and is therefore very important for our cognitive functions. Zinc also helps carry toxic copper out of the liver and out of the body.

Zinc is an indispensable trace element involved in many vital processes in the body, and should therefore be taken in in sufficient quantity.

Without zinc our body cannot carry out the functions that protect it and keep it healthy. A severe zinc deficiency can therefore make us properly ill.

A zinc deficiency has a strong effect on our energy balance, on the skin, hair and nails, on the hormonal system, on our defences and on the sense organs, among other things.

That leads to symptoms such as:

• rashes
• dry, flaky skin, eczema
• acne
• dizziness
• tiredness
• seeing black spots
• a strongly pounding heart
• migraine
• delayed wound healing
• brittle hair
• hair loss
• tinnitus
• sleep problems
• painful periods
• thyroid problems
• mood swings
• poor concentration
• infertility
• raised blood sugar values
• growth problems in children and adolescents
• greater susceptibility to infection
• more infections and ulcers in the mouth (such as aphthous ulcers or inflammation of the lining of the mouth)
• disturbed sense of smell and taste
• vision problems and dry eyes

A zinc deficiency is responsible for problems with the nails, such as soft, brittle nails, ridges in the nails, white spots on the nails and missing half-moons.

In certain situations our body uses considerably more zinc, or can absorb less of it, so that a deficiency can arise.

A higher need for zinc can arise:

• with a one-sided diet
• with regular alcohol consumption or smoking
• with liver disease or stomach disease
• with bowel disease and bowel surgery
• with tumours
• with exposure to heavy metals
• with diabetes
• with an inherited disorder of zinc metabolism
• with infectious disease
• with inflammation
• under stress
• after heavy sweating, such as after sport or a sauna
• during growth
• in pregnancy and while breastfeeding
• in older age
• when taking certain medicines such as laxatives, the contraceptive pill, antacids, lipid-lowering drugs or cortisone preparations

You can raise your zinc intake by eating foods that are rich in it.

Zinc from animal sources:

• oysters
• beef
• pork
• poultry
• fish and seafood
• dairy products
• eggs

Zinc from plant sources:

• pulses: beans, lentils, chickpeas
• nuts and seeds: pumpkin seeds, cashews, almonds, sunflower seeds
• wholegrain products: oats, quinoa, wholegrain rice, wholegrain bread
• mushrooms: shiitake
• vegetables: spinach, broccoli, cabbage leaves, radishes, artichokes, onions
• tofu: a good source of zinc particularly for vegetarians and vegans
• sprouts and microgreens (sprouts harvested later, which have already grown small leaves)
• nettle leaves and parsley
• raw honey

Tip: phytates, found in many plant foods, can inhibit the uptake of zinc. You can reduce the phytate content by soaking, sprouting or fermenting pulses and grains, and so improve zinc uptake. Vitamin C can improve the absorption of zinc as well. Simply eat zinc-rich foods together with foods rich in vitamin C and raise your zinc uptake naturally.

It is of course best and most natural for our body to take in zinc from food, where it comes alongside other vital nutrients. Agricultural soil is now so poor in zinc, though, that even organic products contain too little. That makes it hard to cover our need for zinc through food alone.

It can therefore matter that we supplement zinc, both preventively (to avoid deficiency) and during illness, when the need for zinc rises.

Below we look at the recommendations of the German Nutrition Society and at those of orthomolecular medicine. The German Nutrition Society sets its dosage very low, which can just about prevent an acute deficiency. To really feel the effect of zinc in the body, considerably higher doses are needed, and those are what orthomolecular medicine recommends.

The German Nutrition Society's recommendations for zinc

The German Nutrition Society recommends the following dosage for zinc, to avoid deficiency:

• infants (0–4 months): 1.5 mg a day
• infants (4–12 months): 2.5 mg a day
• children (1–4 years): 3 mg a day
• children (4–7 years): 4 mg a day
• children (7–10 years): 7 mg a day
• children (10–13 years): 9 mg a day for boys, 8 mg a day for girls
• adolescents (13–15 years): 12 mg a day for boys, 10 mg a day for girls
• adolescents (15–19 years): 14 mg a day for boys, 11 mg a day for girls
• adults (19–65 years): 11–16 mg a day for men, 7–10 mg a day for women
• adults (65+ years): 11–16 mg a day for men, 7–10 mg a day for women
• pregnant women: 7–13 mg a day, depending on the stage of pregnancy
• breastfeeding women: 11–14 mg a day

Source: German Nutrition Society

With certain illnesses or special health conditions the need for zinc can be higher. The German Nutrition Society recommends discussing intake with a doctor in such cases.

• infectious disease: 25–30 mg a day (but not over the long term without medical supervision)
• chronic illness: 15–25 mg a day, depending on how severe the illness is and on individual needs
• wound healing and after surgery: 20–30 mg a day, to support wound healing
• skin conditions: 15–30 mg a day for acne or eczema
• vegetarians and vegans: plant foods contain phytates, which inhibit zinc uptake. Raising the zinc intake by around 50% of the recommended daily amount may be necessary.

Recommendations for zinc in orthomolecular medicine

Orthomolecular medicine, which aims to treat illness and raise wellbeing through nutrients, recommends far higher doses. If in doubt, intake should be discussed with a doctor — particularly where interactions with medicines being taken are possible.

General prevention and health:

• adults: 15–30 mg a day
• children (1–4 years): 5–10 mg a day
• children (4–10 years): 10–15 mg a day
• adolescents (10–19 years): 15–20 mg a day

Support during illness:

• acute infection: 30–50 mg a day for a limited period (during the infection, for example)
• chronic illness: 25–40 mg a day, depending on severity and under medical supervision
• skin conditions (acne, eczema): 30–50 mg a day
• wound healing and after surgery: 25–40 mg a day
• vegetarians and vegans: 20–30 mg a day

There are a great many zinc supplements on the market in different forms, each offering different properties and advantages.

Here are the most common forms of zinc preparation:

Zinc gluconate

• the most commonly used form in food supplements
• good bioavailability
• available as tablets and lozenges

Zinc citrate

• zinc bound to citric acid
• good absorption; often easier on the stomach than other forms
• available as capsules, tablets or powder

Zinc orotate

• zinc bound to orotic acid
• good absorption; said to work particularly effectively inside the cells
• mostly available as capsules

Zinc sulfate

• zinc bound with sulphuric acid
• high zinc content; can irritate the stomach (best taken after eating)
• available in liquid form, as capsules or tablets

Zinc picolinate

• zinc bound to picolinic acid
• very good bioavailability
• available as capsules and tablets

Zinc acetate

• zinc combined with acetic acid
• high rate of absorption, often used to treat colds
• available as lozenges and capsules

Zinc methionine

• zinc bound to the amino acid methionine
• very good bioavailability; gentle on the stomach
• available as capsules and tablets

Zinc oxide

• an inorganic form of zinc
• contains a high amount of elemental zinc; lower bioavailability
• often found in products such as creams and ointments, but also in tablet form

Liposomal zinc

• zinc encapsulated in liposomes
• very high bioavailability; more efficient uptake into the cells
• available in liquid form or as capsules

Tips on taking zinc supplements

To make sure our body can take up zinc well, it should not be taken immediately before, after or together with coffee, black or green tea, milk and dairy products, or iron preparations. These can inhibit zinc uptake. Proteins and organic acids, along with vitamin C such as from citrus fruit, raise the uptake.

Zinc tends to be absorbed better on an empty stomach. Some people do not tolerate that well, though, and can get stomach trouble, nausea or abdominal pain. If you notice that sensitivity in yourself, take zinc with a little food that is as low in phytates as possible.

One more tip for a cold or flu: it is best to raise your zinc intake as soon as the first symptoms appear. It works better still combined with vitamin C. Zinc and vitamin C are the great pair for colds and for infectious illness generally.

Signs of overdosing on zinc supplements

With an acute zinc overdose (too high a dose over a short period) the following symptoms can occur:

• nausea and vomiting
• diarrhoea
• abdominal cramps
• headaches

With a chronic zinc overdose (high doses taken over a long period), zinc can build up in the body and lead to zinc poisoning:

• Copper deficiency: both minerals use similar transport routes for absorption in the gut. A high zinc intake can inhibit the uptake of copper and lead to a copper deficiency. Signs of a copper deficiency: anaemia, a weakened immune system and neurological problems.
• A suppressed immune system: paradoxically, too much zinc can weaken the immune system and raise susceptibility to infection.
• A chronically high zinc intake can lower „good" HDL cholesterol, which can raise the risk of cardiovascular disease.
• A metallic taste in the mouth
• Digestive problems

A zinc overdose is very rare, though. Only at doses above 150 mg a day can the metabolism of other minerals such as copper, iron, chromium or manganese be disturbed. That is because different metals with similar properties can displace and influence one another in the body.

Zinc can interact with various medicines, affecting both the uptake and effectiveness of zinc and the effect of the medicines. These include antibiotics, penicillamine, diuretics, antacids, ACE inhibitors, corticosteroids, immunosuppressants and oral contraceptives. If you take medicines, please read the package insert and discuss taking zinc supplements with your doctor.