Want to get rid of a cold fast? Try zinc

The season of stuffy noses, sore throats and persistent coughing is fast approaching. In fact, for some, it’s already underway with recent figures already showing a rise in cases of influenza, according to swabbing samples analysed by the UK Health Security Agency (UKHSA) last week.

Soon, many of us will be hunkering down at home with boxes of tissues and mugs of Lemsip, trying our very best to rid ourselves of dreaded winter colds and flu. Some favour herbal remedies and will squeeze a dollop of honey or mix a spoonful of ginger into their tea. Others opt for over-the-counter methods and stock up on ibuprofen or paracetamol to ease their fever and pains.

But are we all overlooking a vital mineral which could be the key to a strong and healthy immune system? Zinc tablets are often touted as the number one supplement for immunity – but evidence on their efficacy is mixed. So, is zinc really the answer to colds and flu, should we all be taking it, and what other powers does it hold?

What is zinc?

Zinc is an essential mineral and our bodies use it in countless ways, says Dr Naila Aslam, a GP at Central Health London. “We hold small amounts in various parts of our bodies, predominantly our muscles and bones, but we don’t actually store a large reserve of it in our bodies to use which means it’s very important that we consume enough in our diet.”

It’s absorbed in the small intestine and then sent into the blood where it binds with various carrier proteins, mostly albumin, and is transported around the body. As it travels through the bloodstream, zinc is taken up by a range of different cells where it plays a key role in enzyme reactions, Dr Aslam says. According to the NHS, men need to consume 9.5mg and women 7mg of zinc each day.

Can zinc really help with a cold?

One of zinc’s most important roles is boosting the immune system by supporting its normal function and the development of immune cells, explains Rebecca McManamon, a consultant dietitian – hence why it’s commonly touted as a staple supplement in the colder months.

A deficiency can lead to a weakened immune response and leave you more susceptible to infection. A 2017 study in Nutrients points to this being more common among elderly people as they’re less likely to consume enough zinc in their diet.

However it’s important to note that zinc’s powers may lie in its ability to reduce the duration of a cold rather than preventing one altogether, Dr Aslam says. A recent wide-ranging review by the Cochrane Collaboration examined 34 studies involving 8,526 participants and discovered most participants with zinc supplementation experienced little to no reduction in their risk of developing a cold. However, when used as a treatment, zinc was found to help reduce the duration of an ongoing cold.

Therefore whilst preventative supplementation is unlikely to stop you from catching a cold, “some recent studies suggest that starting zinc early, within 24 hours of symptoms onset, can potentially reduce some people’s colds by one to two days”, Dr Aslam says.

However, as McManamon points out, zinc’s real powers may lie in potentially preventing infections in people with a reduced immune system caused by autoimmune diseases, infections, or ageing. In a 2024 review published in Frontiers in Nutrition, zinc supplementation was found to decrease the incidence of infections in elderly people, whilst a 2024 review in Biological Trace Element Research explored zinc paired with vitamin D as a potential treatment for viral infections.

“It is worth discussing with your doctor or dietitian if you should take zinc if you have a condition causing impaired immunity,” McManamon concludes.

What other powers does zinc hold?

Elsewhere, zinc is involved in wound healing, McManamon says, with one wide-ranging review in Nutrients highlighting its crucial role throughout the entire process – from membrane repair to scar formation.

Likewise, it’s the key to healthy locks with one of the most notable symptoms of deficiency being hair loss, Dr Aslam says. A 2013 study in Annals of Dermatology highlighted zinc’s role in the formation of hair follicles, whilst another published in the Journal of Immunology Research explored its importance in the production of keratin, a protein essential for strong, resilient strands.

Zinc is also important for cognitive function due to its antioxidant and anti-inflammatory properties, McManamon explains, with some studies suggesting it may protect against age-related cognitive decline. A 2022 review in Biomolecules found that several neurological conditions may be affected by disruptions in zinc levels – including stroke and Alzheimer’s disease. A zinc deficiency may result in cognitive decline and an increase in oxidative stress, it concluded.

Are there any dangers in taking a zinc supplement?

“Zinc has a complex relationship with copper. They compete for absorption in the gut so if we consume too much of it, we could end up with a copper deficiency,” McManamon explains.

Additionally, we can only absorb a certain amount of zinc which means there’s no value to taking supplements if you consume enough in your diet, Dr Aslam says. She suggests trying a multivitamin first or consulting your GP if you’re concerned about your zinc levels.

Multivitamins tend to contain a more tolerable concentration of the essential mineral but “it is important to check the levels [of zinc] and not aim for 100 per cent RNI,” McManamon notes.

Which foods are high in zinc?

As most of us consume enough zinc from our diets, McManamon advises increasing your dietary sources like seafood, wholegrains, and occasionally having red meat. If you want to boost your immunity throughout winter it’s entirely possible to consume enough zinc from a balanced diet whether you’re a meat eater or plant-based. These are some of the richest food sources (per 100g) of zinc according to Dr Aslam:

In the UK, severe zinc deficiency is rare Dr Aslam explains. However elderly people, and those with restrictive diets and chronic gastrointestinal issues may be at risk.

As zinc is absorbed in the small intestine, people with inflammatory bowel disease (IBD), coeliac disease, and bariatric surgery patients are more likely to experience a zinc deficiency. “These people have severe gut problems and – in some cases – may have parts of their intestine removed which can massively impact zinc absorption,” Dr Aslam explains.

Older and frailer people or those with a restrictive diet or eating disorder may also experience a zinc deficiency because they’re less likely to consume enough in their diets, Dr Aslam adds. “A lot of my elderly patients who rely on a diet of bread, butter and tea or who eat very small amounts of food throughout the day are at a much higher risk of deficiency.”

“If we feel dietary intake is insufficient, particularly in groups at higher risk of deficiency, we advise supplementation daily,” says Dr Aslam. “Excessive zinc supplementation can be harmful and also cause gastric side effects, so it is always best you check with your GP.”

Additionally, people with a plant-based diet may find they’re less able to absorb zinc because of the presence of phytates – anti-oxidant compounds found in natural ingredients like wholegrains, beans, nuts and legumes. Whilst they’re highly beneficial and sometimes referred to as the “anti-cancer micronutrients”, phytates can hinder zinc absorption as they bind to essential minerals and vitamins which prevent the body from absorbing them, Dr Aslam explains.

However, if you eat a mixed and varied diet, phytates aren’t likely to dramatically hinder your body’s absorption of zinc. If you’re vegan and concerned about your phytate levels, “UK dietetic guidance endorses using sourdough, yeasted breads, or soaking, sprouting or fermenting legumes” to improve the bioavailability of zinc, Dr Aslam says.

Another cause of zinc deficiency is drinking too much alcohol, Dr Aslam says. This is because chronic alcohol misuse decreases intestinal absorption, increases urinary excretion of zinc, and is heavily associated with poor nutrition, according to a 2018 study.

What are the signs of a zinc deficiency?

The symptoms of a zinc deficiency can overlap with a number of other conditions, Dr Aslam says. However, common signs include:

1. Getting sick often
2. Hair loss in patches
3. Slow wound healing
4. Loss of appetite
5. Diminished sense of smell and taste.

[Source: Daily Telegraph]