A primer on antioxidants and free radicals: How three tiers of antioxidants work in concert to protect our cells.
What allows us to live and our bodies to function are billions of chemical [enzyme] reactions in the body which occur every second. These are essential for the production of energy, which drives all the processes of life such as nervous function, movement, heart function, digestion and so on.
If all these enzyme reactions invariably occurred perfectly, there would be no need for an antioxidant system. However, even our own enzyme systems make mistakes, and the process of producing energy in mitochondria (cellular energy generators) is highly active. When mistakes occur, free radicals are produced.
Essentially, a free radical is a molecule with an unpaired electron.
It is highly reactive, and to stabilize its own structure, it will literally stick on to anything. That "anything" could be a cell membrane, a protein, fat, a piece of DNA, or whatever. In sticking on to something, it denatures that something [disrupts its structure] so that it has to be replaced.
So having free radicals is extremely damaging to the body and therefore the body has evolved a system to mop up these free radicals before they have a chance to do such damage – and this is called our antioxidant system.
Free radicals come from:
• Inside the body (mitochondrial energy production, the P450 detox system in the liver, and immune activity from inflammation)
• And outside the body (poisoning from pesticides, voltile organic compounds, heavy metals, radiation, etc.)
In recent years even more stress has been placed on our antioxidant system because we are increasingly exposed to internal toxins (modern diets), and external toxins (pollution) – which often exert their malign influence by producing free radicals. Therefore, it is more important than ever to ensure good antioxidant status.
Free radicals effectively accelerate the normal ageing process – and antioxidants slow the normal ageing process.
The best example that we have all seen is the effects of smoking. Cigarette smoking produces large amounts of free radicals, and people who have smoked for many years have prematurely aged skin. Smokers also die younger from cancer or arterial disease – problems one expects to see in the elderly.
Conversely, people who live and eat in a healthy way age more slowly.
The Normal Antioxidant System [Take an Electron & Pass It On]
There are many substances in the body which act as antioxidants, but the most important three front line antioxidants are:
• Co-enzyme Q10. This is the most important antioxidant inside the mitochondria, and also a vital molecule in oxidative phosphorylation. Co-Q10 deficiency may also cause oxidative phosphorylation to go slow because it is the most important receiver and donator of electrons in oxidative phosphorylation. People with low levels of Co-Q10 have low levels of energy.
• Superoxide dismutase (SODase). This is the most important super oxide scavenger in muscles (zinc and copper SODase inside cells, manganese SODase inside mitochondria, and zinc and copper extracellular SODase outside cells),
• Glutathione peroxidase. This enzyme is dependent on selenium and glutathione, a 3 amino acid polypeptide, and a vital free radical scavenger in the blood stream.
These molecules [more about them later] are present in parts per million and are at the frontline process of absorbing free radicals. When one of these molecules absorbs an electron from a free radical, both the free radical and the antioxidant are effectively neutralized, but the antioxidants re-activate themselves tby passing that electron back to second line antioxidants such as:
• Vitamins A and beta carotene,
• Some of the B vitamins,
• Vitamin D,
• Vitamin E,
• Vitamin K,
• And probably many others.
These are present in parts per thousand.
Again, these second line antioxidants are neutralized by accepting an electron, but that is then passed back to the ultimate repository of electrons, namely VITAMIN C, which is present in higher concentrations.
Most mammals can make their own vitamin C, but humans, fruit bats and guinea pigs are unable to do so. They have to get theirs from the diet, and Linus Pauling, the world authority on vitamin C (namesake of the Linus Pauling Institute for Micronutrient Research at Oregon State University), reckoned we need vitamin C in gram doses every day. I recommend a minimum of 2 grams of vitamin C daily and for some patients up to six grams. Pauling himself advocated larger doses. The UK government recommended intake of 30mg a day is just sufficient to prevent scurvy, but insufficient for optimal biochemical function (or prevention of chronic disease).
• Paraoxonase (synthesized by the liver) is an antioxidant that sits on good cholesterol (HDL) , protects this and the bad cholesterol (LDL) from oxidation, and is "strongly linked to protection of cardiovascular health." Levels of paraoxonase are determined genetically. This enzyme detoxifies organophosphate pesticides, so if deficient this makes the organophosphates very much more toxic.
• There are many other antioxidants present in vegetables, nuts, seeds and fruits which the body takes advantage of when they are present in the diet.
• Other substances such as melatonin also have profound antioxidant properties.
• Vitamin B12 is an excellent antioxidant… For those with particularly poor antioxidant status [B12 supplementation] provides antioxidant cover and protects from further damage while they take the necessary micronutrients to heal and repair their own antioxidant system.
Have I Got a Problem with Poor Antioxidant Status?
All the above antioxidants can be measured and almost routinely now I measure front line antioxidants** – namely Co-enzyme Q10, Superoxide dismutase (SODase), and glutathione peroxidase.
Co-enzyme Q10 – My experience is that levels in CFS sufferers are almost always down and that they can be corrected by taking Co-enqyme Q10 300mg daily for three months, after which continue with a maintenance dose of 100mg.
Superoxide dismutase (SODase or SOD) – Deficiency can explain muscle pain and easy fatigability in some patients. SODase is [an enzyme that is] dependent on copper, manganese and zinc and I would expect this to be maintained in people taking a multi-mineral. However, when there is a deficiency, these minerals are taken separately. Experience shows that the best results are achieved by copper 1mg in the morning, manganese 3mg midday, and zinc 30mg at night. Low SODase may also result from gene blockages – and these are also looked at when the SODase test is done. Blockages are most often caused by toxic stress, such as heavy metals and pesticides.
Glutathione peroxidase (GSH-Px) – This is made up of glutathione, combined with selenium. There is a particular demand in the body for glutathione. Not only is it required for GSH-Px, which is an important frontline antioxidant, but it is also required for the process of detoxification. Glutathione conjugation is a major route for excreting xenobiotics [toxic foreign chemicals/substances]. This means that if there are demands in one department, then there may be depletions in another, so if there is excessive free radical stress, glutathione will be used up and therefore less will be available for detoxification, and vice versa.
Of course, in patients with chemical poisoning or other such xenobiotic stress, there will be problems in both departments, so it is very common to find deficiencies in glutathione.
If there is a deficiency of GSH-Px, then I recommend that patients eat a high protein diet (which contains amino acids for the body’s endogenous synthesis of glutathione), take a glutathione supplement 250mg daily, together with selenium 200mcg daily [in a multi-mineral].
The second and third line antioxidants – Are largely provided by doing a good “stone age diet” [emphasis on low glycemic index meats/fish/eggs; green & 'salad' veggies; seeds, nuts & their oils; fruits such as berries and apples, with modest amounts of higher GI foods/carbs in the evening; avoids common allergen foods and additives/chemicals as much as possible], and multi-vitamin supplementation.
* Dr. Sarah Myhill, MD, BS, is a UK-based GP and registered nutritionist with a special interest in fatigue, preventive medicine, and patient education. This article is excerpted with kind permission from Dr. Myhill's patient-education website (DrMyhill.co.uk). ®Sarah Myhill Limited, Registered in England and Wales: Reg. No. 4545198.
** Individuals in the UK can, with a doctor's referral, directly order many diagnostic tests by obtaining kits from and mailing samples to Dr. Myhill. See details on these related tests – Antioxidant status profile; Co-enzyme Q10; SODase (superoxide dismutase) studies; and Glutathione peroxidase.
Note: This information has not been evaluated by the FDA. It is generic and is not meant to prevent, diagnose, treat or cure any condition, illness, or disease, nor should this information replace the attention of your healthcare professional. It is very important that you make no change in your healthcare plan or health support regimen without researching and discussing it in collaboration with your professional healthcare team.