While some vitamins and minerals take centre stage, zinc has a way of staying hidden in the wings. But it’s vital for important bodily functions including everything from immunity and wound healing to brain function, growth and even our sense of sight, taste and smell.
Zinc is required by every cell and organ in the body. A component in enzymes that maintain the integrity of proteins in the body, it’s used to regulate gene expression, which creates the building blocks of life.
That means it’s especially important for supporting normal growth and development during pregnancy, infancy, childhood and adolescence. It’s also important in male fertility, because it plays a role in both sexual function and sperm mobility.
| Food (per 100g) | Zinc levels |
| Oysters | 16mg |
| Pepitas | 7.8mg |
| Cashews | 5.6mg |
| Beef | 4.5mg |
| Quick oats | 3.6mg |
| Dark chocolate | 3.3mg |
| Baked beans | 2.2mg |
| Chickpeas | 1.5mg |
| Yoghurt (250g) | 1.4mg |
So why doesn’t zinc get more attention? Because it’s found in a wide range of foods, it’s often assumed that most people already get enough zinc in their diet. But for those who are at risk of deficiency, the effects can be severe. Pregnant and lactating women are among the at-risk groups. Others include those with gastrointestinal, kidney and liver disease, people with sickle cell anaemia and older infants who are exclusively breastfed.
And because zinc is more easily absorbed in a diet high in animal proteins, vegetarians also run a risk of deficiency. In fact, it’s believed that strict vegetarians may need up to 50 per cent more zinc to fulfil their dietary needs. Found in many high-protein foods, zinc is especially rich in red meat, oysters and other shellfish, dairy, seeds, nuts and wholegrain breads and cereals.
The recommended dietary intake of zinc for most women is 8mg per day. Pregnant women will need around 11mg, while those lactating need around 12mg.
A mild deficiency can result in delays in growth and development, suboptimal birth outcomes and impaired immunity. Symptoms of severe deficiency include diarrhoea, impaired appetite, sexual dysfunction, alopecia, and eye and skin lesions.
There’s no evidence that people have experienced adverse effects from eating too much zinc that naturally occurs in food. However, overdoing the supplements may cause several problems, including the suppression of immune responses, a decrease in levels of HDL or “good” cholesterol levels and a reduction in copper trace minerals, which we also need for healthy bodily function.
If you think you might have a deficiency or need a supplement, it’s best to see a doctor first. But for most of us, a diet high in protein-rich food will provide all the zinc we need.
Looking for more nutrition advice or recipes? Check out these blogs.