If you’ve not been inflicted with the “super cold” this autumn, count yourself lucky. People are reporting symptoms of the “worst cold ever” as we enter the first cold and flu season for two years without coronavirus restrictions.
Rest, plenty of fluids and paracetamol are generally recommended for the common cold, and of course, you should test for Covid if you have symptoms such as a cough to rule it out.
But zinc supplements could also help – if taken in moderation.
Taking a zinc supplement may cut how long respiratory infections – such as cold and flu – last, while also easing symptoms, a new review of studies suggests.
Researchers looking at 28 existing studies involving almost 5,500 people found that taking zinc by mouth or as a nasal spray could ward off infection and may make people feel better more quickly.
Respiratory tract infections (RTIs) can affect the sinuses, throat, airways or lungs, but most get better without treatment. Symptoms of an RTI include cough, sneezing, stuffy or runny nose, sore throat, headache and a high temperature.
The new research, in the journal BMJ Open and from experts including from Western Sydney University, did not include data specifically related to Covid-19 cases.
It found that, compared with placebo, taking zinc could prevent five RTIs in 100 people per month, while on average symptoms resolved two days earlier if zinc was taken as a spray or under-the-tongue formula.
Overall, 19 more adults per 100 were likely to still have symptoms seven days into their illness if they had not taken zinc. Meanwhile, there were “clinically significant” reductions in how people graded their symptoms three days into their illness.
“In adult populations unlikely to be zinc deficient, there was some evidence suggesting zinc might prevent RTIs symptoms and shorten duration,” the authors concluded.
“The comparative efficacy/effectiveness of different zinc formulations and doses were unclear.”
Zinc is important for the immune system to function properly and is also vital for wound healing. It is found in foods including oysters, crab, meat, chickpeas, mushrooms, spinach, broccoli and kale. You can also buy zinc supplements from most pharmacies and health stores.
The authors said more research is needed into zinc and pointed to the low quality evidence in some of the studies.
It’s also worth noting that it’s possible to have too much zinc in your diet.
According to the NHS, taking high doses of zinc reduces the amount of copper the body can absorb, which can lead to anaemia and weakening of the bones.
“You should be able to get all the zinc you need by eating a varied and balanced diet. If you take zinc supplements, do not take too much as this could be harmful,” the NHS website says. “Do not take more than 25mg of zinc supplements a day unless advised to by a doctor.”
This article was updated on November 3 to include additional information about zinc supplements from the NHS.