Life Extension Magazine®

Group of researchers examining previous zinc lozenges studies

Snails Pace - Life Extension

The Journal of the American Medical Association reported that taking the correct form and dose of zinc lozenge cuts duration of the common cold by about 50%! The key is initiating zinc acetate lozenges at the very first cold symptom. Delays of 24-48 hours may render zinc lozenges ineffective as too many rhinoviruses have already infiltrated your cells.

Scientifically reviewed by Dr. Gary Gonzalez, MD, in August 2023. Written by: William Faloon.

William Faloon
William Faloon

In 1979, a serendipitous discovery occurred when a 3-year-old girl was battling leukemia. Her leukemia was being treated with chemotherapy, radiation, and zinc. She developed a severe cold during the treatment.1 Due to the cold, the little girl refused to swallow a 50 mg zinc tablet and instead dissolved it in her mouth. Within several hours her cold disappeared and did not return.1

In 1984, findings from the first double-blind human study on zinc lozenges for common colds was published. The results showed that cold symptoms vanished in 86% of people taking zinc lozenges compared to 46% taking placebo lozenges after seven days.1

In 2014, the Journal of the American Medical Association published a synopsis of human trials on the use of zinc lozenges in treating the common cold. The results showed that when the proper dose of zinc is used within 24 hours of first symptoms, the duration of cold miseries is cut by about 50%.2

There are about one billion colds suffered in the United States each year.3 The delay from discovery to mainstream validation of zinc lozenges has caused enormous suffering.

The title of this editorial is “Snail’s Pace.” It refers to the agonizingly slow time (30 years) it took from the discovery that zinc lozenges shorten the duration of cold symptoms to acknowledgment of zinc’s efficacy by the medical establishment.

Snail’s Pace  

The problem today is that most people don’t know how to properly use zinc lozenges to stop colds from taking hold in their bodies. This article will describe a way to reduce your odds of contracting a protracted cold virus this winter.

People often procrastinate, even as their health succumbs to a cold virus that slowly wears them down. The problem with delaying treatment is that after a cold virus invades too many cells, it self-replicates to the extent that it is difficult to achieve relief.

The first step in infection occurs when a cold virus (called rhinovirus) attaches to the linings of nasal cavities in our head. The virus infiltrates cells by attaching to a cell receptor called intercellular adhesion molecule-1 (ICAM-1).4

The proper form and dose of zinc blocks the ICAM-1 receptor, thus preventing the rhinovirus from entering cells and establishing a common cold infection.5

According to an article published this year in the Journal of the American Medical Association, if higher-dose zinc lozenges are initiated within 24 hours of the first symptoms, the mean duration of a cold is 4.47 days compared to 8.68 days in low-dose zinc lozenge users.2

While cutting the duration of cold symptoms almost in half is impressive, we at Life Extension® think it’s possible to stop many colds before they take hold and cause prolonged agony.

We recommend that when the very first cold symptom develops, high-dose zinc lozenges are immediately initiated and continued until symptoms subside. In other words, don’t wait 24 hours to initiate, don’t even wait 24 minutes. Start taking the proper form of zinc lozenge immediately!

Inconsistent Zinc Studies

Human Cell  

Not all clinical trials using zinc lozenges have been successful. The failures, however, provide important insights on what not to do if one expects to shorten their cold duration.

For example, two placebo-controlled studies published in 1987 did not initiate zinc lozenges until 36 hours after cold symptoms presented. In addition, these people who suffered cold symptoms for more than 36 hours also had their sinuses inoculated with different strains of rhinoviruses to make sure they were fully infected. High-dose (23 mg) tightly bound zinc lozenges6 failed in these studies and the doctors concluded that zinc lozenges are “ not therapeutically useful in the treatment of rhinovirus colds.”7

A study published in 1990 used low-dose (4.5 mg) zinc lozenges at the first sign of cold symptoms or within 24 hours of symptoms appearing. This low-dose zinc also failed to provide benefit compared to placebo.8

A study published in 1992 looked at differing forms of zinc lozenges and found that some of them were so tightly bound to their carrier by zinc chelators that they would not release enough free zinc in the throat to block the ICAM-1 receptor.9 The conclusion of this report is that previous studies showing a positive benefit with zinc occurred when lozenges contained the proper carrier to release ionic zinc. Studies published in 1996,10 1997,11 1998,12 2003,5 and 201013 confirm this 1992 finding that the proper form of zinc is required to suppress cold symptoms.

So we know from earlier research why zinc lozenges don’t always work. Fortunately, an abundance of research now demonstrates significant benefit when the right form and dose of zinc lozenge is used within 24 hours of cold symptoms manifesting.2,5,10-14

How To Use Zinc Lozenges
How To Use Zinc Lozenges

Zinc lozenges should ideally be taken immediately upon the very first cold symptom, even if you’re not certain you really have a cold. Take one 18.75 mg zinc acetate lozenge every two waking hours. Please be aware that this is a high dose of zinc and should not be taken over the long term. You should only need to do this for a few days; we suggest no more than three days.

You may not need to suck on zinc for more than one day. If your cold symptoms disappear after sucking on a few lozenges over several hours, then you may not need to take any more until the next time you experience a cold symptom.

Studies That Validate Zinc Efficacy

In 1996, a published study showed that moderate-dose (13.3 mg) zinc lozenges reduced the duration of common cold symptoms. Median time to complete resolution of cold symptoms was 4.4 days in the zinc lozenge group compared to 7.6 days in the placebo arm of the study.10

In 2000, another moderate-dose (12.8 mg) study showed significant reduction in duration and severity of cold symptoms. The number of days suffered was reduced by about 45% in the zinc lozenge group. The mean overall duration of cold symptoms was 4.5 days in the active (zinc lozenge) group compared to 8.1 days in the placebo arm.)14

In a 2002 published study in children with colds, those who used zinc lozenges suffered 7.5 days of symptoms compared to 9.0 for nonuse.15 What was impressive about this study is that the median number of colds declined to zero when children supplemented daily with a zinc lozenge compared to a median of 1.3 colds contracted when not supplementing. During the time of zinc supplementation, only 4.1% of the children were prescribed an antibiotic drug compared to 36.2% when they were not supplementing.15

A 2008 published study on adults was done using 13.3 mg zinc lozenges within 24 hours of cold symptoms developing. Cold durations, on average, for those who received the zinc lozenges, were 4.0 days compared to 7.1 days in the placebo arm. The severity of cold symptoms in this study was markedly less in the zinc lozenge group.16

In 2011, a review of 13 placebo-controlled human trials was published that examined the effect of zinc lozenges on common cold episodes of natural origin. Five of the trials used a total daily zinc dose of less than 75 mg and all these studies found no effect. Three trials used zinc acetate in daily doses of over 75 mg. The pooled result of these three studies using higher dose zinc acetate showed a 42% reduction in the duration of colds.17 Five trials used other zinc salts (like gluconate) in daily doses of over 75 mg. The pooled result from these five trials showed a 20% reduction in the duration of colds.17 This analysis showed zinc acetate to be the preferable form to be used in a lozenge designed to shorten the duration of cold symptoms.

In 2014, the Journal of the American Medical Association published an article indicating that cold duration could be slashed almost in half if higher-dose zinc lozenges are taken within 24 hours of the first symptom. This review concluded:

“Our findings are consistent with 2012 American Academy of Family Physicians guidelines and with the 2013 dietary supplement fact sheet of the National Institutes of Health. Both support use of zinc supplementation within 24 hours of onset of the common cold.” 2

Overcoming The “Adverse” Effects

Overcoming The “Adverse” Effects  

The research on zinc lozenges reveals consistent complaints of unpleasant taste, constipation, and a metallic feel in the mouth in response to higher potency zinc lozenges, especially zinc gluconate lozenges.17,18 Some people have told me over the years they’d rather suffer longer with the cold than endure the unpleasant effects of the zinc gluconate lozenges.

These adverse effects prompted Life Extension® to scour the scientific literature to identify a way of delivering enough zinc acetate in a lozenge without causing unpleasant effects.

The best solution involves a novel way of combining a moderate-dose (18.75 mg) of zinc acetate into a lozenge (without added chelators) flavored with peppermint oil. This lozenge is more palatable than many commercial brands while delivering an ideal potency of the proper form of zinc to block the ICAM-1 receptor.5

We think that these better-designed zinc acetate lozenges will motivate people to start sucking on them as soon as the first cold symptom manifests, thus providing an opportunity to prevent the rhinovirus from taking hold in one’s body.

Even if you are not certain an itchy nose, sneeze, or runny nose is really a cold, it will not hurt to suck on these new zinc lozenges to make sure. The immune-boosting effects of zinc are profound and the cost is quite low.

An argument could also be made that if you are in the presence of someone suffering from a cold, sucking on a few of these lozenges may block your ICAM-1 receptors from allowing their rhinovirus to latch on and infect your cells.

My Personal Experience

I suffered my last head cold around 1983. As I have written in the past, whenever I feel even the slightest symptom of a cold or flu virus, I immediately take high doses of garlic,18-23 melatonin,24-28 lactoferrin,29-33 DHEA,34-38 and zinc lozenges along with 1,200 mg a day of the OTC drug cimetidine.39

This aggressive regimen has kept me from suffering a debilitating cold or flu infection for over 30 years.

When I develop cold symptoms, I use a wide variety of high-dose zinc lozenges and keep sucking on them until symptoms disappear. I’ve never had to use zinc lozenges more than 12 hours to eliminate cold symptoms. My symptoms usually disappear within six hours of immediately sucking on zinc lozenges.

I’m convinced that if I did not aggressively start high-dose zinc lozenge therapy, I would have contracted a cold virus that would have lasted a week or more. I’ve heard this anecdotally from others; i.e. if they start sucking on zinc lozenges at the very first symptom of a cold, a full-blown common cold does not manifest.

History Of Zinc And The Common Cold

In this month’s issue, we feature an in-depth article by the pioneer of zinc lozenges in the prevention and treatment of the common cold. George Eby investigated every form of zinc before developing a lozenge that is palatable, potent, and provides a form of zinc (acetate) that binds to cellular ICAM-1 to keep out rhinoviruses.

The low cost of zinc lozenges makes them a wise choice to stockpile ahead of time in one’s home, office, and suitcase. The last obstacle you want to face when a cold symptom manifests is trying to find a 24-hour pharmacy that sells a poor-tasting lozenge that may not be the form or potency needed to block your ICAM-1 receptors against an invading cold virus.

It is regrettable that the serendipitous discovery about zinc and the common cold occurred in 1979, yet most victims in 2014 still do not know how to use zinc to shorten cold duration.

For longer life,

For Longer Life

William Faloon


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