Does Zinc Really Work? Yup! Vitamin C? Not so much...

Of course, I'm talking about supplementation of Zinc and Vitamin C and their effects on preventing the common colds and reducing their severity and duration. They both talk the talk...but which walks the walk?

Vitamin C (Ascorbic Acid)

Vitamin C's efficacy in preventing and treating common colds has been the subject of debate for over half a century. In theory, Vitamin C supplementation should increase immune function. In practice...not so much. In studies? Last year, the Cochrane Collaboration published an extensive review of the literature on Vitamin C and cold prevention/duration/severity. Their criteria for selecting studies to review are strict, allowing only the highest of quality with the least amount of bias.

Vitamin C for preventing and treating the common cold

The failure of vitamin C supplementation to reduce the incidence of colds in the general population indicates that routine prophylaxis is not justified. Vitamin C could be useful for people exposed to brief periods of severe physical exercise. While the prophylaxis trials have consistently shown that vitamin C reduces the duration and alleviates the symptoms of colds, this was not replicated in the few therapeutic trials that have been carried out. Further therapeutic RCTs are warranted.

Essentially, other than very specific cohorts of the population (atheletes and soldiers in extreme cold), Vitamin C doesn't walk the walk. Understand that this is a review of over 60 studies on the efficacy of Vitamin C on cold prevention and treatment by a rather unbias group of reviewers. Coming from Cochrane, this is pretty damning evidence that Vitamin C supplementation for colds is a bust, and a waste of money.

(Why doesn't ascorbic acid supplementation work? My personal opinion, based on my own review of the literature, is that Serum levels of vitamin c and uptake are two different animals. Unless extremely high doses are administered intravaneously, vitamin c uptake efficiency is relatively independent of serum levels. Other factors, blood glucose being the most influential, determine the amount of ascorbic acid uptake. Glucose and ascorbic acid use the same receptor sites to cross cell membranes. Insulin resistance, which a great deal of Americans have, and elevated blood glucose will greatly diminish the uptake of vitamin c. Mainly because high blood sugar is much more toxic than high levels of ascorbic acid, therefore its usually flushed before it can used.

The results of the study above really shed some light on the issue. Athletes and soldiers undoubtedly have higher insulin sensitivities and lower blood sugar, allowing for greater vitamin c uptake.)

Zinc

Zinc is an essential mineral for immune function and wound healing, among other things. Go to any CVS or Walgreens and in the "Flu/Cold" section you'll undoubtedly find a full section of lozenges, half of which are fortified with Zinc. These are generally used for the treatment of colds. If you take a left on isle 4, you'll probably notice, at the very end, Zinc pills for supplementation. These are generally used for prevention of colds...and, of course, other things. The debate on the efficacy of Zinc supplementation for the treatment and prevention of the common cold is similar to that of Vitamin C. Many of the studies of the past 30 years have seen mixed results, suggesting it has no effect.

Hot of the press is another review by the Cochrane Collaboration in which they examine 15 trials..

Zinc for the common cold

Selection criteria:

Randomised, double-blind, placebo-controlled trials using zinc for at least five consecutive days to treat, or for at least five months to prevent the common cold.

The results were much more supportive than those in the Vitamin C review:

Zinc administered within 24 hours of onset of symptoms reduces the duration and severity of the common cold in healthy people. When supplemented for at least five months, it reduces cold incidence, school absenteeism and prescription of antibiotics in children.

This study explains why I hardly get sick. I typically begin using Zinc lozenges at the very first sign of a cold (Vitamin D, too). I get some sleep and symptoms are gone in 24 hours. I also eat plenty of red meat and other foods that are high in zinc, which explains why I hardly ever begin to get a cold in the first place.

So, although Vitamin C gets most of the publicity, Zinc is winning, Duh! It talks the talk and walks the walk.

Here's more info from the Cochrane Review just published:

Zinc inhibits rhinoviral replication and has been tested in trials for treatment of the common cold. This review identified 15 randomized controlled trials, enrolling 1360 participants of all age groups, comparing zinc with placebo (no zinc). We found that zinc (lozenges or syrup) is beneficial in reducing the duration and severity of the common cold in healthy people, when taken within 24 hours of onset of symptoms. People taking zinc are also less likely to have persistence of their cold symptoms beyond seven days of treatment. Zinc supplementation for at least five months reduces incidence, school absenteeism and prescription of antibiotics for children with the common cold. People taking zinc lozenges (not syrup or tablet form) are more likely to experience adverse events, including bad taste and nausea. As there are no studies in participants in whom common cold symptoms might be troublesome (for example, those with underlying chronic illness, immunodeficiency, asthma, etc.), the use of zinc currently cannot be recommended for them. Given the variability in the populations studied (no studies from low- or middle-income countries), dose, formulation and duration of zinc used in the included studies, more research is needed to address these variabilities and determine the optimal duration of treatment as well as the dosage and formulations of zinc that will produce clinical benefits without increasing adverse effects, before making a general recommendation for zinc in treatment of the common cold.

Bravo... Star & Flag... I wish more studies were done about this... Seems like Big Pharm doesn't mind flu season being around, so I'm not surprised this information is not known to many..

Thank you again, I myself have the flu right now , heading to buy some Zinc.

reply to post by DevolutionEvolvd


Thanks for all of the info.

I have never heard of zinc being used for the clod/flu before, but of course I've heard about using vitamin C. Although vitamin C has never effectively gotten rid of any sickness for me, no matter how much orange juice I drink.

reply to post by FoxStriker


Try to get the sugar free lozenges. There's not much sugar in them anyways, but the less sugar the better.

reply to post by dalan.


The problem with orange juice is the sugar content. As I was saying in the OP, elevated blood sugar will inhibit Vitamin C uptake and effectively render it useless.

There is a massive difference between the RDA and what should be taken to fight a cold or illness. As a teenager, my doctor once "prescribed" me 3000-5000mg of vitamin C SEVERAL TIMES A DAY to fight off a nasty cold. He was in his 70's and was very "no nonsense".The great majority of studies use lower amounts and, not surprisingly, show little difference from placebo.

reply to post by SmokeandShadow


....but where in nature are you going to find that much Vitamin C at once?

Originally posted by DevolutionEvolvd
reply to post by FoxStriker

 

Try to get the sugar free lozenges. There's not much sugar in them anyways, but the less sugar the better.

Artificial sweetners are all bad.Stevia is natural and has been used safely for hundreds of years,just like sugar.Your body is designed to break down sugar. High density sweetners like high fructose corn syrup will be broken down first by your body,causing anything else you consume with it to be turned to fat.
Vitamin C has never helped me recover from a cold or the flu.That is just my personal experience.Zinc is toxic and should be used cautiously and in small amounts.I have friends who have become ill from taking too much.It doesn't take much to toxify yourself.
I was told by a nutritionist to use vitamin E as it will boost your natural immune system. Vitamin E needs to be used cautiously because it is a fat soluable vitamin and your body can store it. Vitamin C is water soluable and cannot be stored.It was recommended to me to take 1- 400mg tablet once a day at the first sign of symptoms and continue for no more than 4 days because I usually take a multi-vitamin each day.I have used this method for the last 5 years with great success.

Preply to post by lonegurkha



The minuscule amount of artificial sweetener in a lozenge is hardly harmful. However, its important to avoid any spike in blood sugar to avoid the immuno suppresive effects of elevated blood glucose. And your grasp of toxicity is a little off. Toxicity is highly dependent on dose. Zinc is toxic IF you ingestion too much. So is water.

And the solubility of vitamins has to do with how they're excreted. It's not an issue of storage.

It really is not needed to supplement vitamin C or zinc if you are healthy person with proper nutrition to begin with. That being said, the vast majority does not have proper nutrition and downs packets of Emergen-C or takes Zicam when they think they have the flu. If you commonly get the flu/cold or what-have-you, instead of being reactive or loading yourself with a specific vitamin or mineral, you can do the following;

1. Regularly exercise.
2. Cleanse your body of toxins. Liver, kidney, lymphatic, heavy-metal cleanses, etc. Then continue to watch what toxins do enter your body, and eliminate or reduce them - fluoride, chlorine, nicotine, caffeine, carcinogens, or phosphoric acid? And the list goes on even more. Other than, obviously, cleansing your body, doing this will increase energy levels and lower depression and anxiety.
3. Evaluate your nutrition. Frankly, you can't have crappy nutrition and assume zinc or vitamin C tablets will always help you. Nutrition could be a topic in itself. And if you are taking a daily vitamin, think about switching to a whole food supplement - you will also get natural enzymes and cofactors.
4. Reduce stress. This is a big one. Besides helping with common colds and other sicknesses, reducing stress will help with CVD.
5. Stop taking OTC and prescription drugs. They suppress symptoms and further put the body into a state of imbalance. Also, avoid vaccines for "the flu".

And regarding things like Emergen-C that provide a megadose of a specific vitamin or mineral - be careful. Taking in large excesses to try to "kill" the cold can have side effects; too much vitamin C has an effect on the GI tract and too much zinc blocks the absorption of other essential minerals.

the x factor is that these are supplements, meaning that they aren't ingested properly with other things that they should be in that would help you absorb the vitamins more naturally and efficiently. like how they say "take close to meals", most people will really just eat them with fast food and think everything will be fine. supplements are bs anyway, unless you have to take them, don't. just eat healthy... if you don't eat healthy, then don't complain about your health issues to people.

these studies are kinda silly to me... why study supplements instead of real food/healthfood intake? pharmagenda

x factor number two is blood type. Type A's benefit greatly from it - but are better off with injections then capsules. BUT, a mineral deficiency will render the added C useless as well as any other supplements in the vitamin world. So, when testing, if all the bodies don' have exactly the same composition from blood type to mineral balances, then the study is pointless. Now, if one is low in Vit D, all bets are off.

Vitamin C is still useful though. I trust Linus Pauling.

OP, please see this video regarding orally administered vitamin C and uptake.

Originally posted by Konah
It really is not needed to supplement vitamin C or zinc if you are healthy person with proper nutrition to begin with. That being said, the vast majority does not have proper nutrition and downs packets of Emergen-C or takes Zicam when they think they have the flu. If you commonly get the flu/cold or what-have-you, instead of being reactive or loading yourself with a specific vitamin or mineral, you can do the following;

I'm personally don't think supplementing is anything, and in some cases harmful (Vitamin D and Magnesium would be exeptions). However, once symptoms become evidence, exercising and cleansing and yoga won't really help as treatment. That's where zinc comes into play.

Originally posted by shagreen heart
the x factor is that these are supplements, meaning that they aren't ingested properly with other things that they should be in that would help you absorb the vitamins more naturally and efficiently.

There's some truth to this post. Especially when talking about fat soluble vitamins. People, and researchers, underestimate the value that nutrients have in whole foods compared to isolated nutrients. Many times bioavailability is substantially different between the two.

reply to post by crankyoldman


I tell you what...find me some randomized, controlled studies in which the efficacy of blood-type specific diets are tested. Then I'll listen...

reply to post by finalword


It's definitely useful, or essential. However, I don't think daily supplementation is warranted if one is consuming a somewhat healthy diet.

Originally posted by DevolutionEvolvd
reply to post by SmokeandShadow

 

....but where in nature are you going to find that much Vitamin C at once?

In the livers of most animals that synthesize the "vitamin"...

reply to post by DevolutionEvolvd

Of course, you won't die from lack of vitamin C, but megadosing will contribute greatly to good health. Read Linus Pauling's book. You can't get megadoses of vitamin C from healthy diet unless all you're eating is vitamin C rich foods. The only way is through supplementation.

reply to post by unityemissions


The liver is probably the most nutritious part of any animal (organ meats and bone marrow). They filter everything...and are extremely nutrient dense. But there really is no comparison to the ascorbic acid in animal liver (a few mg/liver) vs supplements (500-1000/pill). And Linus Pauling, and others, are suggesting hyperdosing. There's absolutely no possible way.