Two people besides me on this SSC thread report that zinc works well for them. One uses the same brand listed. The other uses HealthSpan Elite Zinc Defence Lozenges, and I don’t see anything in the ingredients list that looks like those shouldn’t work.
(Edit: but I now notice the dose seems lower than ideal. Taking lots of them might be sufficient. Slightly more detail in linked thread.)
So maybe there are two products on the market! Some possible explanations for why the podcast host didn’t mention them:
They might not have been on the market at the time (podcast recorded in 2016, oldest review of the lozenges is from two years ago).
I haven’t checked whether they ship outside the UK. If not, he might have disqualified them before or after investigating. (Edit: they do seem to ship outside the UK.)
He might just not have found them. I don’t know how thoroughly he searched.
Negative evidence:
I did get a cold a few months back. (At the end of one day, I realised that I was feeling a bit blergh and decided to take lozenges the next day. Next day I already had a sore throat. I took lozenges anyway, and while I’m not confident it made it go away faster, I do think the symptoms were less unpleasant than my historical colds. I didn’t keep a log of them, though.)
(But that’s still only one cold in about a year and a half.)
Overall I’m more confident than I was when I posted this.
I had another cold a few weeks ago. Only the second since I posted this, but I haven’t been going out much, so. Timeline was that I got my covid booster on a Saturday (4th December), and felt shaky that evening and the next day. Monday I went to my work christmas party. Tuesday I felt a bit under the weather, I think including sore throat, but attributed it to tiredness and alcohol, I didn’t have zinc. Wed-Fri my sore throat got increasingly worse, I started sucking zinc but only like two a day out of forgetfulness. Then it got super unpleasant, I had various combinations of lethargy, brain fog, sore throat and sneezing for a few days, while I started taking zinc in earnest. I took all of Monday and some of Tuesday off work, and was basically feeling fine on Wednesday—still gunked up, but no pain or mental effects. (I actually feel like I might still be a bit phlegmy, two weeks later, but I don’t know if I’m just noticing my normal level of phlegminess more than I would otherwise.)
(It’s also possible this was Covid, I took a negative LFT on the Sunday so I guess not? But I only took one, and this was around when Omicron was starting to take off in London.)
My partner caught it from me and I encouraged them to take zinc too, but they find the lozenges super unpleasant so they didn’t have as many as I’d recommend. I think their experience was less bad than mine, but their baseline is also worse than mine so it might just be that the same level of suckiness registers less for them.
Not sure how to weight this. I didn’t take enough or quickly enough for it to be strongly negative evidence, plus my booster might have confused things. If I’d cleared up fast enough after taking things seriously, and/or if my symptoms were only mild, it might count as weakly positive. But I think it lasted about as long as we might expect and was worse than normal for me. I guess “neutral” is unlikely, so “slightly negative” it is? (Ideally I’d be more specific here than just “true or false” but that sounds like a lot of effort.)
And negative evidence: philip_b’s comment here. “As for helping with common cold, I have no idea if they are helping. Maybe, slightly. In the beginning I thought that maybe I am noticing some positive effect, but it could easily be placebo. I also have a hunch that maybe they help with throat symptoms but not with nose symptoms.” The hypothesis predicts an effect size larger than “maybe, slightly”.
More negative evidence: I got a cold a week ago. Symptoms started on the friday, I took several lozenges a day for the next three days, then stopped when I still had symptoms on monday. Unlikely to be covid, I had a negative LFT on the sunday and a negative PCR on either the wednesday or thursday. (I assume PCR anyway, I’m in a study but I don’t know the details. They posted me a test kit, I completed it and posted it back, they said I was negative.)
(Editing in more stuff when it comes up):
2023-08-21: Woke up with a sore throat. LFT was negative for covid. Had 4-5 lozenges throughout the day, next day had the kind of throat that felt like I was recovering from a cold. Had 1 or 2 that day, I think I felt completely fine on day 3.
2023-08-29: Woke up with a sore throat. Didn’t test for covid. Had 4-5 lozenges throughout the day. Day after I think I felt fine, had one or two, still felt fine day 3.
2023-09-03: Woke up feeling the start of a cold, but this one felt more in the nose than the throat than previously. Had 4-5 lozenges throughout the day. Was still feeling it the next day, don’t remember if it had changed much. Kept taking them, I think I stopped on day three when I still had a cold. I think it was pretty mild as colds went, didn’t take any time off work, and I think it remained more in the nose than throat compared to normal. Took an LFT on day 5, negative for covid.
It’s unusual to have three so close together. Could be something like “I never actually fully fought off the first or second one”? Idk. The “symptoms are more in nose than throat” feels like it could be a clue for why they sometimes fail, that’s a thing to pay attention to in future.
2023-09-18: Woke up with mild sore throat. Took three throughout the day. Next day still had mild sore throat, took another three. I don’t really remember what happened after that, but it didn’t ever become a full-blown cold.
Positive evidence:
Two people besides me on this SSC thread report that zinc works well for them. One uses the same brand listed. The other uses HealthSpan Elite Zinc Defence Lozenges, and I don’t see anything in the ingredients list that looks like those shouldn’t work.
(Edit: but I now notice the dose seems lower than ideal. Taking lots of them might be sufficient. Slightly more detail in linked thread.)
So maybe there are two products on the market! Some possible explanations for why the podcast host didn’t mention them:
They might not have been on the market at the time (podcast recorded in 2016, oldest review of the lozenges is from two years ago).
I haven’t checked whether they ship outside the UK. If not, he might have disqualified them before or after investigating. (Edit: they do seem to ship outside the UK.)
He might just not have found them. I don’t know how thoroughly he searched.
Negative evidence:
I did get a cold a few months back. (At the end of one day, I realised that I was feeling a bit blergh and decided to take lozenges the next day. Next day I already had a sore throat. I took lozenges anyway, and while I’m not confident it made it go away faster, I do think the symptoms were less unpleasant than my historical colds. I didn’t keep a log of them, though.)
(But that’s still only one cold in about a year and a half.)
Overall I’m more confident than I was when I posted this.
More evidence:
I had another cold a few weeks ago. Only the second since I posted this, but I haven’t been going out much, so. Timeline was that I got my covid booster on a Saturday (4th December), and felt shaky that evening and the next day. Monday I went to my work christmas party. Tuesday I felt a bit under the weather, I think including sore throat, but attributed it to tiredness and alcohol, I didn’t have zinc. Wed-Fri my sore throat got increasingly worse, I started sucking zinc but only like two a day out of forgetfulness. Then it got super unpleasant, I had various combinations of lethargy, brain fog, sore throat and sneezing for a few days, while I started taking zinc in earnest. I took all of Monday and some of Tuesday off work, and was basically feeling fine on Wednesday—still gunked up, but no pain or mental effects. (I actually feel like I might still be a bit phlegmy, two weeks later, but I don’t know if I’m just noticing my normal level of phlegminess more than I would otherwise.)
(It’s also possible this was Covid, I took a negative LFT on the Sunday so I guess not? But I only took one, and this was around when Omicron was starting to take off in London.)
My partner caught it from me and I encouraged them to take zinc too, but they find the lozenges super unpleasant so they didn’t have as many as I’d recommend. I think their experience was less bad than mine, but their baseline is also worse than mine so it might just be that the same level of suckiness registers less for them.
Not sure how to weight this. I didn’t take enough or quickly enough for it to be strongly negative evidence, plus my booster might have confused things. If I’d cleared up fast enough after taking things seriously, and/or if my symptoms were only mild, it might count as weakly positive. But I think it lasted about as long as we might expect and was worse than normal for me. I guess “neutral” is unlikely, so “slightly negative” it is? (Ideally I’d be more specific here than just “true or false” but that sounds like a lot of effort.)
And negative evidence: philip_b’s comment here. “As for helping with common cold, I have no idea if they are helping. Maybe, slightly. In the beginning I thought that maybe I am noticing some positive effect, but it could easily be placebo. I also have a hunch that maybe they help with throat symptoms but not with nose symptoms.” The hypothesis predicts an effect size larger than “maybe, slightly”.
More negative evidence: I got a cold a week ago. Symptoms started on the friday, I took several lozenges a day for the next three days, then stopped when I still had symptoms on monday. Unlikely to be covid, I had a negative LFT on the sunday and a negative PCR on either the wednesday or thursday. (I assume PCR anyway, I’m in a study but I don’t know the details. They posted me a test kit, I completed it and posted it back, they said I was negative.)
(Editing in more stuff when it comes up):
2023-08-21: Woke up with a sore throat. LFT was negative for covid. Had 4-5 lozenges throughout the day, next day had the kind of throat that felt like I was recovering from a cold. Had 1 or 2 that day, I think I felt completely fine on day 3.
2023-08-29: Woke up with a sore throat. Didn’t test for covid. Had 4-5 lozenges throughout the day. Day after I think I felt fine, had one or two, still felt fine day 3.
2023-09-03: Woke up feeling the start of a cold, but this one felt more in the nose than the throat than previously. Had 4-5 lozenges throughout the day. Was still feeling it the next day, don’t remember if it had changed much. Kept taking them, I think I stopped on day three when I still had a cold. I think it was pretty mild as colds went, didn’t take any time off work, and I think it remained more in the nose than throat compared to normal. Took an LFT on day 5, negative for covid.
It’s unusual to have three so close together. Could be something like “I never actually fully fought off the first or second one”? Idk. The “symptoms are more in nose than throat” feels like it could be a clue for why they sometimes fail, that’s a thing to pay attention to in future.
2023-09-18: Woke up with mild sore throat. Took three throughout the day. Next day still had mild sore throat, took another three. I don’t really remember what happened after that, but it didn’t ever become a full-blown cold.