Zinc deficiency: how to recognise and prevent it

Zinc: a trace-element with many benefits

Zinc is a very important trace-element involved in multiple processes in the human body.

It is mainly contained in the bones, teeth, hair, skin, liver, muscle - and in men - the testes.

Zinc is a component of several hundred enzymes including a large number of nicotinamide adenine dinucleotide (NADH) dehydrogenases, RNA and DNA polymerases, and DNA transcription factors, as well as alkaline phosphatase, superoxide dismutase and carbonic anhydrase (1).

In practical terms, European health authorities recognise that zinc helps protect cells against oxidative stress, and supports normal immune system function, DNA synthesis, cognitive function, fertility, testosterone levels, and skin, bones, nails and hair.

Zinc is popular with, amongst others, sportspeople, especially bodybuilders. It often features in cosmetic and/or dermatological products and even healing balms (2).

Symptoms of zinc deficiency

A lack of zinc can cause one or more of the following symptoms (3):

• diarrhoea;
• loss of appetite;
• open sores and wounds that don’t heal;
• sudden, unexplained weight loss;
• excessive sugar cravings;
• deterioration in mood (apathy);
• lack of concentration;
• prevalence of respiratory infections and immune dysfunction in general;
• decreased sense of taste and/or smell;
• night vision and eye health problems;
• erectile dysfunction in men;
• abnormal development of sex organs (in young people in the growth stage);
• decreased alertness;
• memory problems;
• delayed growth in children;
• complications in pregnancy;
• skin problems (acne);
• psoriasis;
• nail and hair loss.

However, these symptoms can also be caused by other deficiencies and diseases, so we’d recommend consulting a health professional for an accurate diagnosis if you are affected by any of them.

Lack of zinc: what are the causes?

As you might imagine, zinc deficiency is usually the result of under-consumption of foods that contain it.

However, it’s worth noting that certain groups of people are at higher risk of zinc deficiency:

• those taking diuretics or certain other medications (such as proton pump inhibitors);
• those suffering from diabetes mellitus, sickle cell disease, chronic kidney disease, liver disease, problems with alcohol consumption or malabsorption, and those who have undergone bariatric surgery;
• those who have suffered acute, serious, stressful health events (such as sepsis, burns or head trauma);
• elderly patients who are institutionalised or house-bound;
• pregnant women;
• those eating a vegetarian diet (or other restrictive diets).

Good to know: phytates reduce the bioavailability of zinc

Plant seeds contain phytate anions which are their primary means of storing phosphorus and minerals. But these phytates, or phytic acid, are considered anti-nutrients insofar as they make nutrients less bioavailable to the body, nutrients that include iron, calcium… and zinc (4)!

To reduce the phytate content of plant foods such as oilseeds and legumes, it’s important to pre-soak them and to eat them cooked or sprouted. This way, you’ll obtain the benefits of zinc, vegetarians included.

Zinc-rich foods

As is the case with iron, zinc from animal protein is more bioavailable, and the best dietary sources of zinc are all animal-source foods. Having said that, it’s entirely possible to meet your zinc requirements from a vegetarian diet, provided you follow the above-mentioned advice.

Here’s a list of the top zinc-rich foods in descending order (5) :

• oysters;
• calves’ liver;
• beef;
• veal;
• lamb;
• crab;
• crayfish;
• beef or pork liver;
• pork;
• egg yolk;
• wheatgerm;
• sesame seeds and tahini;
• clams;
• lobster;
• chicken;
• shiitake mushrooms;
• pumpkin seeds.

Which are the best zinc supplements for preventing deficiency?

Besides eating a balanced, high-protein diet, especially animal protein, you can ensure an adequate daily zinc intake by taking a dietary supplement.

There are various forms of zinc available in supplement form, including:

• zinc orotate: zinc can be combined with orotates, organic mineral salts found in dairy products, amongst others, which significantly increases its bioavailability (one such example is the product Zinc Orotate) (6);
• zinc methionine: zinc is also thought to be better absorbed when combined with the amino acid L-methionine. What’s more, this form may offer 4-6 times more antioxidant potency than standard zinc salts such as zinc oxide or zinc sulphate (one such supplement is L-OptiZinc®) (7);
• zinc L-carnosine: studies have for many years concluded that combining zinc with the amino acid L-carnosine may help protect the digestive system and reduce the discomfort of acid reflux (try Zinc L-Carnosine) (8-9);
• zinc bisglycinate: combining zinc with two glycine molecules improves the trace-element’s stability, protects it from stomach acidity and thus ensures optimal uptake (that’s precisely the case with Advanced Zinc Lozenges, an excellent zinc supplement in the form of suckable tablets).