True or False: Antioxidants work to enhance the immune system?

Question

This is an argument between a co-worker and I:

"The exact example is CoQ10 acts as an antioxidant and enhances the immune system." I believe these are two separate systems,(one acting on free rads after oxidation the other fighting bacteria and viruses) she thinks that because something is an antioxidant it therefore enhances the immune system (the antioxidant helping out the immune system).

I think I'm right but I would like to know what other people think.

Answer 1

Hi Meep.  This is not an easy question, primarily because you and your co-worker have not defined what is meant by "enhance".

Antioxidants are vital to a healthy immune response, but does that mean they "enhance" the immune response?

The immune/inflammatory response (to infection, injury, etc.) involves the production of high levels of oxidants (hydrogen peroxide, superoxide, hypochlorus acid, etc.).  These oxidants need to be controlled/contained by anti-oxidants.  So, while anti-oxidants do not necessarily increase immune system function/activity, they do play a MAJOR role in limiting the toxic effects of that activity and, thus, in preventing excessive harm to healthy tissues from the immune response.

CoQ is a central player in the so-called Antioxidant Network.  So, optimum levels of CoQ will certainly "enhance" the body's ability to properly "regulate" the body's response to the immune response!

Lastly, many "antioxidants" (e.g. Vitamin C, Vitamin E, zinc, selenium, etc.) play non-antioxidant, but critical roles in immune function.

So, the bottom line to your challenging question, is really a question of the definition of "enhance"!

Hope this was helpful.

Best wishes.

Answer 2

As Crouching Doggie said, antioxidants are not really a definitive part of the immune system.  CoQ 10 or "ubiquinone" is definitely something you need, although unless you are particularly old or sick or you have certain mitochondrial diseases, you can make your own.  Its only specific function that I know of in the human body is as the final step of ATP production in the mitochondria, so I'm not sure what that's supposed to have to do with the immune system.

It is true that there is a great deal of research into what antioxidants may or may not do for the body, and some people think that the reason that those who eat larger amounts of fruits and vegetables are healthier is at least in part because they are high in antioxidants.  The fact is that the jury is still out on what, if any, effect supplementation of antioxidants really has.  There are even some experiments that show that certain antioxidants (notably vitamins A and E) are actually associated with HIGHER mortality, so go figure.  I have also not really heard this immune system theory before--mostly I hear about cancer and cardiovascular disease supposedly being prevented by antioxidant supplementation.  I also think that vague claims like "enhancing the immune system" are what sketchy product manufacturers do to get around FDA regulations on what they can say on their packaging.  

Simply put, I think you're right too, but I doubt it will do any good for you to argue it with your co-worker.  It's not my experience that people who believe in those things are easily persuaded by logic or facts.  ;-)  But I wish you luck trying.

Answer 3

In the simplest of terms, antioxidants are "free radical scavengers."  Free radicals are just residual products of natural metabollic processes which have the ability to harm genetic material.

The immune system is an entirely different matter.  The host immune system acts as our defense from pathogens (bacteria, viruses, etc.).  Sometimes our immune system goes a little overboard and begins attacking the wrong antigen, e.g. a protein that's otherwise non-harmful or even part of our own bodies.  The immune system, per se, doesn't perform "free radical scavenging."

Are both processes good?  Certainly, but they work in parallel to enhance our health, not so much to synergistally work together.

I hope this makes some sense.

Answer 4

The actions/consequences of antioxidants and antioxidant supplementation are hard to grasp.  

Do antioxidants enhance the immune system ? Yes.  It is hard to plan and interpret studies in this field of research for numerous reasons - it's very hard to measure the amount of free-radicals in a cell at any give instance in time (oxidative stress), it's also very difficult to monitor the oxidative state of the antioxidants, their concentration within the cell, whilst at the same time measure some useful parameter of immune functionality.  When you start to look at it in a human, you then have calculate the pharmacodynamics of the supplements you're giving (i.e. whats the concentration of the antioxidant in the blood, in tissue, in the cellular compartment of interest).

It's often very appropriate to consider the body's processes as isolated systems - such as the immune system, the cardiovascular system, etc, once you get down to the molecular level, and examine what's going under the hood, these distinctions aren't really meaningful.

The details as to how antioxidants enhance the immune system, and the various mechanisms proposed for their effects are tedious. I'll try to give a brief account of a few however.

Firstly, free radicals, for all the bad press they get, are very important to the immune system.  Many immune cells actively/intentionally make and use them to destroy pathogens.  For the most part the cells that make these reactive oxygen species (ROS) keep them sequestered away inside vesicles (like balloons inside the cell) so that the immune cell itself doesn't get damaged by the ROS it has made.  When these cells encounter a pathogen, they engulf it and throw it into the balloon carrying all the free radicals.  Unfortunately, free radicals are rather unpredictable, and quite often they leak out during this process and thus cause the immune cell a good deal of stress (oxidative stress).

As it happens, cells have realised this is a potential problem and so have antioxidants inside the cell waiting to mop up the runaway radicals.  This reduces the oxidative stress of the cell and prevents it from being destroyed.  This is a good example of enhancing the effectiveness of an immune process.

In some cases the ROS production is out of control (certain types of sepsis, and our body's natural levels of antioxidants are not sufficient to help - so in this case antioxidant supplementation could be highly beneficial (see references).

You mention CoQ10 specifically, and it has also shown immune enhancing capacity.  Often times, when we receive a vaccination, we are given a small amount of the pathogen/virus etc that we are wanting to form immunity against.  It is common practice to add into the vaccine a variety of factures that will stimulate the immune system to develop this immunity more rapidly.  This is called an adjuvant and often times CoQ10 (ubiquinone) and/or some of its related compounds will be used for this.  This is a good example of a chemical enhancing an immune response.

CoQ10 is found in several places in a cell and in the blood also.  It is found in many of the different membranous structures in the cell, including the mitochondrion, lysosome, endoplasmic reticulum etc. It has even shown a role in enhancing the uptake of the pathogens into the immune cells (as mentioned in the last paragraph), as they are guided into the free-radical containing vesicles.

CoQ10 also can exist as a free radical (like most antioxidants) and it is capable of converting other antioxidants, such as tocopherol and ascorbic acid (vitamins E and C) back to their native forms after they have gathered up free radicals (so it resets them so they can be used again).   Indeed, when there are lots of free radicals in the cellular environment, coQ10 is used up preferentially before Vit E or A.

I hope this is of help for you. Although I agree that products contain things like 'enhances the immune system' and they probably aren't basing that on too much hard evidence.  Also, it is the case the antioxidants have been shown to have detrimental effects in some studies, but the mechanism/cause for this is not clear yet. And there is not much evidence that antioxidant (including CoQ10) levels are significantly increased in the tissues, by intake of supplements.

Here are a few bits and bobs from some journals that came to mind, but there's a lot more info available if you do a little digging.

Sorry to have disagreed with your argument.

>>some studies

1.  European Journal of Clinical Nutrition (2002) 56, Suppl 3, S5-S8. doi:10.1038/sj.ejcn.1601476

One of the most widely accepted theories proposed to explain ageing is the free radical theory, according to which oxygen-derived free radicals cause age-related impairment through oxidative damage to biomolecules, with mitochondria being the main target of free radical attack. Since oxygen radicals are needed for many metabolic and physiological processes, an equilibrium between radical production and their antioxidant-linked inactivation is required to preserve health. Thus, senescence is the result of an imbalance between free radical production and antioxidant defences, with concomitant oxidative stress and age-dependent functional decline. This process is especially evident in the immune cells, which use free radicals in their functions and suffer a senescent deterioration probably linked to oxygen stress. Conversely, several laboratories, including our own, have shown that antioxidants preserve an adequate function of immune cells against homeostatic disturbances caused by oxidative stress, such as that involved with age. Therefore, since the immune system is an indicator of health and a longevity predictor, the protection of this system afforded by dietary antioxidant supplementation may play an important role in order to achieve a healthy ageing.

2. Int Immunopharmacol. 2004 Mar;4(3):327-47.

    Immune cells: free radicals and antioxidants in sepsis.

    Victor VM, Rocha M, De la Fuente M.

There is an increasing body of evidence which implicates ROS, released by immune cells, as important mediators in sepsis and septic shock. During a normal immune response, antioxidants serve to down-regulate the ongoing immune response, mostly through modulation of proinflammatory mediators. During sepsis, however, there is an overstimulation of the immune system, and thus, the effect of antioxidants and other checkpoint molecules such as cytokines are overwhelmed by the proinflammatory mediators. Understanding the signal transduction mechanisms used by these mediators that regulate immune response could facilitate specific interventions to prevent host tissue injury in sepsis. In fact, based on the known protective effects of antioxidants, they could offer an alternative of the treatment of sepsis because they do not exert an indiscriminate stimulating effect on the immune cell function. Antioxidants increase tissue protection from oxidative stress and are effective and safe in a large range of concentrations.

3. Vaccine

Volume 16, Issue 16, October 1998, Pages 1504-1510

Coenzyme Q10 in vesicles composed of archaeal ether lipids or conventional lipids enhances the immuno-adjuvanticity to encapsulated protein

B. Makabi-Panzu*, G. D. Sprott*, Corresponding Author Contact Information and G. B. Patel*

Cellular accumulation, tissue distribution, and immuno-adjuvanticity were evaluated for liposomal CoQ10 prepared from either distearoylphosphatidylcholine:dicetylpho... (4:1:5, mol. ratio) (conventional liposomes) or from the total polar lipids of the archaeon Methanosarcina mazei (archaeosomes). Liposomal CoQ10 vesicles of approximately 100 nm diameter, containing up to 179 μmol of CoQ10 per mg of lipid have been evaluated using J774A.1 macrophages and Balb/c mice. Archaeosomes uptake by J774A.1 macrophages was better than with the conventional liposome, and the incorporation of CoQ10 enhanced the uptake of both lipid vesicle types. All vesicle types were detected in the liver and spleen of mice (4–27% of injected dose) within 3 h of intraperitoneal injection. Moreover, incorporation of CoQ10 into lipid vesicles enhanced the immuno-adjuvanticity of both conventional liposomes and archaeosomes, to achieve approximately a doubling in the titres of BSA-specific antibody in sera to 169 and 430 μg ml−1, respectively. Increases in IgG1 and IgG2a/2b accounted for most of the CoQ10-induced increases in anti-BSA titres. These results are rationalized on the basis of surface hydrophobicity and opsonization changes induced by the presence of CoQ10 in vesicles. We suggest that liposomal CoQ10 has potential as a new generation of vaccine delivery system to enhance the immune response. Its use as a novel delivery system may be particularly effective under pathological conditions where the occurrence of an oxidative stress condition significantly impairs the immune system functions.

Answer 5

you are correct, your friend is wrong.  i would go into it but it is getting too late at night!

Sorry.