Can zinc help my cold?
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Sniffles, sneezing, stuffy nose, coughing, and feeling "under the weather" are all symptoms that many adults experience on average 2-3 times per year, and school children up to 12 times per year. Achoo! Cue the common cold: a respiratory virus affecting the upper respiratory tract and the most frequent infectious disease in humans.
While more than 200 viruses have been implicated in the common cold, the most common viruses responsible for this lovely collection of symptoms are known as rhinoviruses, followed by coronaviruses, and adenoviruses. Symptoms often appear 2-3 days after viral exposure and typically last 7-10 days. While there is no "cure" for the common cold, there are some key vitamins and minerals to consider reaching for when those symptoms first appear, with one of them being the mighty zinc!
What does the research say?
Zinc is an essential trace mineral that plays a critical role in over 300 enzymatic reactions in the body. From immune system function to DNA synthesis, this mineral was first found to have a positive impact on recovery from the common cold in 1984. Surprisingly, it was only shortly before that in the mid-1970s, that zinc was officially deemed an "essential" mineral for the human body, based on research conducted by Dr. Prasad in the 1960s, who discovered that zinc-deficient patients suffered from immune disturbances and growth issues which improved with zinc supplementation.
While there have been mixed results in some studies over the years, recent studies and reviews have reported benefit to supplementing with zinc in the early onset of cold symptoms, ideally within 24 hours of symptom onset, resulting in a 33% reduction in the length of cold duration at a dose of 75-90mg of zinc (in a lozenge form) per day.
A recent 2020 scientific review found that zinc lozenge supplementation reduces the common cold by 2.25 days in otherwise healthy adults.
How does it work?
Studies show that zinc status is essential for a properly functioning immune system, and that deficiency may be a contributing factor for viral illnesses. Particularly in sensitive populations like children and the elderly, supplementation reduces the risk of pneumonia and common cold, and the incidence of respiratory tract infection.
Zinc has both direct and indirect antiviral effects. It seems to interfere with viral replication, helping to curb the strength of the virus in the body. Additionally, this mineral helps to stabilize your body's cells to prevent viruses from attacking.
Does the form matter?
Most of the research on zinc and the common cold has looked at zinc lozenges in the form of zinc gluconate or zinc acetate, with both providing favourable results.
There seems to be a particular benefit to having zinc directly contact the inside of your mouth. The local interaction of zinc with your upper respiratory tract triggers the mouth-nose BCEC (biologically closed electric circuit) which researchers believe explains the rapid therapeutic response to zinc lozenges. The circuit moves electronics from the nose into the mouth and in doing so, moves positively charged ions (like zinc molecules) from the mouth into the notes! Zinc is then believed to bind to the same receptors that the pesky rhinovirus attaches to the inside of the nose, interfering with viral attachment and further preventing the formation of viral proteins. Move over, rhinovirus!
The downside of zinc lozenges is that many are made with additional ingredients like flavour enhancers or sweeteners to improve the taste. One particular ingredient that interferes with zinc absorption is citric acid, often found in "hard candy" zinc lozenges. Another option would be to open up a zinc capsule, dissolve the contents in water, and swish it around your mouth for some time to improve the direct contact.
While the common cold may be with us for a long time yet, don't let it hang on longer than it needs to. Take good ongoing care with a healthy diet and lifestyle, but if (and when) those sniffles appear, reach for that zinc supplement, pour yourself a warm cup of herbal tea, and settle in for some rest. That'll help you get back on your feet in no time!