# Free radicals

Category: Metabolism

Free radicals are reactive molecular fragments that occur even in healthy cells, and can damage the cell. When unsaturated oils are exposed to free radicals they can create chain reactions of free radicals that spread the damage in the cell, and contribute to the cell's aging.

10 passages · 1 author · 2001–2021 · Most-cited: [Ray Peat](https://bioenergeticoracle.com/md/voices/ray-peat/index.md)

Canonical page: https://bioenergeticoracle.com/concepts/free-radicals

## Synthesis

**Free radicals** are reactive molecular fragments that occur even in healthy cells, and can damage the cell. [Source 1] Ray Peat's perspective on free radicals is deeply rooted in the early 20th-century work of *Moses Gomberg*, who first demonstrated their physical existence, and *W.F. Koch*, a chemistry professor who immediately applied this discovery to biology, postulating that **quinones** in the mitochondria handle energy via free radical reactions. [Source 4, 6] This view was initially rejected by mainstream science, which held that free radicals were purely toxic and incompatible with life, a stance that led to the government twice attempting to jail Koch. [Source 4, 5] Peat argued that the official view only began to shift in 1954 when Barry Commoner's group measured free radicals in living tissues, around the same time Denham Harman formulated his mitochondrial free radical theory of aging. [Source 5]

Peat distinguished sharply between *productive* and *destructive* free radical activity. He explained that when thyroid and oxygen are working properly, the **electron transport chain** involves lots of free radical activity, but it is all productive and protective; the faster oxygen is run through the mitochondria under the influence of thyroid, the less free radical damage occurs to the cell's structure. [Source 3] He likened this to a laboratory with negative pressure, where a rapid flow of electrons keeps the system tightly ordered, preventing them from "wandering off" and causing damage. [Source 9] In contrast, slowing metabolism or removing oxygen creates a state where electrons have no place to go, generating toxic free radical damage. [Source 9] This framework directly opposes the old "rate of living" theory, which posited that slowing oxygen consumption would slow aging. [Source 9]

The primary source of destructive free radical cascades in the body, according to Peat, is the ingestion of **polyunsaturated fats** (PUFAs). He demonstrated that even at room temperature, oils like safflower oil spontaneously oxidize, sucking up oxygen and forming toxic liquid peroxides, a process greatly accelerated at body temperature and catalyzed by iron and heavy metals. [Source 3, 10] Peat stated that PUFAs are the main material that causes an "explosion" of free radicals once the process is started by factors like endotoxin and nitric oxide. [Source 3, 10] He cited a century of studies, including a 1927 experiment, showing that a fat-free diet extends lifespan and prevents cancer, and noted that animals deficient in PUFAs have a metabolic rate about 50% higher and can survive extreme physical trauma that kills normally fed animals. [Source 3, 10]

Peat also warned that substances typically considered pure antioxidants, such as synthetic **ascorbic acid**, can become potent free radical generators in the presence of catalytic heavy metals like iron. He recounted a chemist's finding that pure vitamin C in distilled water produced a concentration of free radicals equivalent to a killing dose of X-rays, and noted that even a few milligrams of the synthetic form triggered allergic reactions he did not experience from high-vitamin C foods. [Source 2] He extended this pro-oxidant potential to plant polyphenols and flavonoids, explaining that in a reduced cellular state, vitamin C and similar substances can react with ferrous iron to produce the highly toxic **hydroxyl radical**. [Source 7] The most important source of hydroxyl radicals during stress is the ferrous ion released when *heme oxygenase* degrades heme, a process exacerbated by carbon monoxide or hypoxia which keeps iron in its reduced, radical-producing state. [Source 7] Peat maintained that the main protective action of substances like aspirin and bioflavonoids is not merely scavenging radicals, but improving the oxidative state of the cell to minimize their production. [Source 7, 8]

## People also ask

### How did Ray Peat distinguish productive from destructive free radical activity?

Peat argued that when thyroid and oxygen function properly, the electron transport chain involves rapid, protective free radical activity that prevents damage. Destructive damage occurs when metabolism slows or oxygen is removed, leaving electrons with no place to go and generating toxic radicals.

### Why did Peat consider polyunsaturated fats a major source of free radical damage?

Peat demonstrated that polyunsaturated fats spontaneously oxidize, forming toxic peroxides in a process accelerated by body temperature and catalyzed by iron. He stated they are the main material causing an "explosion" of free radicals once triggered by factors like endotoxin.

### What was Peat's concern about synthetic vitamin C and free radicals?

Peat warned that synthetic ascorbic acid can become a potent free radical generator in the presence of catalytic heavy metals like iron, producing hydroxyl radicals. He noted that even a few milligrams triggered allergic reactions he did not experience from high-vitamin C foods.

## Related concepts

- [Antioxidants](https://bioenergeticoracle.com/md/concepts/antioxidants/index.md)
- [Endotoxin (Lipopolysaccharide, LPS)](https://bioenergeticoracle.com/md/concepts/endotoxin-lipopolysaccharide-lps/index.md)
- [Albumin](https://bioenergeticoracle.com/md/concepts/albumin/index.md)
- [Cancer metabolism](https://bioenergeticoracle.com/md/concepts/cancer-metabolism/index.md)
- [Menopause](https://bioenergeticoracle.com/md/concepts/menopause/index.md)
- [Saccharide](https://bioenergeticoracle.com/md/concepts/saccharide/index.md)

## Cited passages

Passage numbers match the `[Source N]` markers in the synthesis above.

### Source 1 — Glossary

Ray Peat · Glossary

> Free radicals
>
> Free radicals are reactive molecular fragments that occur even in healthy cells, and can damage the cell. When unsaturated oils are exposed to free radicals they can create chain reactions of free radicals that spread the damage in the cell, and contribute to the cell's aging.

### Source 2 — One Radio Network: Great Monthly Talk with Ray Peat PhD (August 17, 2020)

Ray Peat · Interview · Aug 17, 2020

> **Patrick Timpone:** What could be in some of these things, vitamin C and other supplements as we know them, that could be causing the allergic thing? Just extra things, extras that they put in there?
>
> **Ray Peat:** No, something was happening in the substance itself. A chemist, a free radical chemist, published an article describing taking... chemically the purest form of synthetic ascorbic acid that was available not from a tablet but straight from the it was called reagent grade and putting 500 milligrams in a liter of distilled water then putting it in an apparatus that detects free radicals and the apparatus showed that Nothing but the pure vitamin C and the pure water was producing the concentration, a steady production of free radicals that a killing dose of x-rays would have produced shining on the water. And he said, isn't that amazing that a person can swallow this and their stomach isn't killed? the way the x-ray produced radicals would kill it. He said that shows something about our tissue defenses.
>
> **Patrick Timpone:** So it's not the vitamin C itself. I mean, obviously, we get good stuff with oranges and fruit. It's the way that this stuff is made in the lab.

### Source 3 — Endotoxin, Free Radicals, and Inflammation — KMUD July 2009

Ray Peat · Interview · 2009 · http://www.l-i-g-h-t.com/files/herb-doctors-bowel-endotoxinnew.mp4

> **Caller:** When you eat those foods you are ingesting free radicals?
>
> **Ray Peat:** Well, very quickly yes. An experiment that I did illustrates how even at room temperature they spontaneously oxidize; I put a rubber hose in a bottle of I think it was safflower oil, and put the other in a glass of wasser; and just at room temperature, over a few hours the bottle in effect (check, doesn't change the meaning though) respiring, it was sucking oxygen up, and drawing water up into the tube; the oxygen was combining with the unsaturated fats and in the process forming liquid peroxides, which are toxic free radicals.
>
> **Caller:** Inside the body is worse.
>
> **Ray Peat:** Yeah, it's much faster at that temperature and we have catalytic amounts of iron and heavy metals floating around to accelerate the reaction.
>
> **Andrew Murray:** What are free radicals? What foods prevent and promote? What about foods and endotoxin?

### Source 4 — Herb Doctors: Endotoxins

Ray Peat · Interview · Nov 19, 2010

> **Ray Peat:** WF Koch was a Michigan chemistry professor who went into medicine. He was at the University of Michigan at the time Moses Gomberg had discovered free radicals. It was 20 or 30 years before chemists would believe that such a thing existed. But Koch was there at the university, saw the stuff, understood its properties and started thinking about what that type of reaction would mean in the body. And he proposed that we have free radicals in the form of quinones in our mitochondria handling energy, creating all of these functions (anti-inflammatory, antiviral, anti-tumour, and so on). And he created a whole range of substances, some more powerful than others, and began giving them to cancer patients and allergy patients and even infected cows. (There was a study in California in which they cured various animal diseases with his so-called anti-cancer reagent.) The famous Albert Szent-Györgyi, who got a Nobel prize related to respiration and vitamin C research, based practically his whole career on working out the meaning of Koch's work with the quinones. The vitamin K ubiquinone is the substance that came much later to be discovered in the mitochondria. The government twice tried to put Koch in jail, saying that it was inconceivable that people could have free radicals in their cells and that it would be toxic if they did. But then it turned out that exactly the type of chemical, the quinone, that Koch had postulated turned out to be the essence of how human life creates energy.

### Source 5 — Dangers of sadistic science: Determinism vs process thinking

Ray Peat · Newsletter · 2016

> In 1954, Barry Commoner's research group described their measurements of free radicals in living tissues. Until then, the official view was free radicals were very toxic and completely incompatible with life. It was around this time that it occurred to Denham Harman that the production of free radicals in the process of oxidative metabolism might be a mechanism to explain the degenerative processes of aging. Harman's earlier work as a Shell petroleum chemist (including work on insecticides) defined his view of biological free radicals. He suggested that the mitochondrion is "the true biological clock" of aging. Although supplementing antioxidants could reduce some diseases in his experimental animals and increase their average lifespan, he found that they didn't increase the maximum lifespan. He concluded that supplemented antioxidants couldn't penetrate to the mitochondrial matrix, and that free radicals produced there damaged the mitochondrial DNA, resulting in metabolic errors that increased the rate of free radical production, leading to a constant acceleration of the rate of decline.
>
> This statement of the "rate of living" in terms of damage to the genes of somatic cells appealed to mainstream biologists, who were just learning about the new DNA double-helix model of the gene, and who were already committed to the "wear and tear" theory of aging and cancer, involving random "somatic mutations," which were thought to be caused mostly by radiation. An extrinsic cause of age-associated diseases, ionizing radiation, had been replaced by an intrinsic, inescapable cause, mitochondrial respiration.
>
> By 2006, at the age of 90, Harman seemed to be fully convinced that mitochondrial deterioration was unavoidable, an "inborn" aging process (IAP). Since his original theory proposed toxic free radicals as the cause of cancer as well as aging, the "IAP" would suggest that cancer too is ultimately the result of an inborn tendency, though he had found that antioxidants could reduce the cancer death rate in animals. His experiments in the 1960s and '70s contributed to the use of vitamin E and vitamin C, and to the development of increased optimism about the possibility of radically extending the maximum lifespan. For example (1961), he found that the most highly unsaturated fats were the most carcinogenic, and (1976) he showed that peroxidation damages brain function, increasing learning errors.

### Source 6 — Suppression of Cancer Treatments — Politics & Science, 2001

Ray Peat · Interview · 2001

> **Jon Barkhausen:** I didn't know that. When did the free radical theory start?
>
> **Ray Peat:** Well, about 1905, I think. 1900-1905 was when Moses Gomberg was demonstrating them. But, immediately, Koch was putting it into theoretical thinking about what cells were doing. And he applied it to the concept of polymerization and blood clotting as his first thing . And he knew that in healing a wound or a cancer, blood clotting is one of the first things that happens. And the clotting abnormalities are characteristic of cancer. And it turned out that, for places like DuPont, the polymerization was in fact a very important practical industrial principle using the free radical. But Koch anticipated even industrial thinking, within just a few years of starting to work on it. He was applying it theoretically and practically, to devise both explanations for disease and therapies.
>
> **Jon Barkhausen:** He seems like quite a brilliant man.
>
> **Ray Peat:** Yeah, so quick to apply knowledge that was very clear and definite. But other people couldn't accept it because it just didn't seem to fit the low standard that was common in chemistry and all branches of science and biology at that time.

### Source 7 — 100 Years of Cancer Metabolism

Ray Peat · Newsletter · 2016

> For more than 50 years, the public has been very conscious of the biological dangers of free radical oxidation, and the protective effects of antioxidants. Oxidative damage, such as lipid peroxidation, is a seriously harmful phenomenon. Aspirin and the bioflavonoids are powerfully protective against lipid peroxidation and the DNA mutations and protein damage triggered by the most toxic free radical, the hydroxyl radical. They can act directly as hydroxyl radical scavengers, so it has been assumed that this is the way they work in cells, but their main action there seems to be by improving the oxidative state of the cell. Some radicals are produced in mitochondria, but effective mitochondrial oxidation of glucose minimizes that source of radicals. The most important source of hydroxyl radicals during stress is the ferrous ion, a reduced form of iron, for example the iron released when heme oxygenase degrades heme and produces carbon monoxide. Carbon monoxide, or hypoxia, increases the cell's reductive power, keeping iron in the reduced state that produces hydroxyl radicals (Zhang and Piantadosi, 1992). When the cell is in a reduced state, vitamin C is one of the reductants reacting with iron to produce hydroxyl radicals (Hara, et al., 2009). Like aspirin, the antioxidant/pro-oxidant flavonoids typically increase mitochondrial respiration and reduce inflammation. When cancer metabolism increases the amount of lactate in the blood, increased breathing lowers the carbon dioxide in the blood (Gargaglioni, et al., 2003), and the loss of CO2 affects metabolism and physiology at all levels. When CO2 is increased, the redox balance of the cell is shifted in the direction of oxidation (Mel'nychuk, et al., 1977), the use of glucose for growth and fat synthesis is inhibited, and the Krebs cycle is activated (Mel'nychuk, et al., 1978). Inescapable cellular excitation shifts cells into the characteristic cancer-like metabolism, and various anesthetics (e.g., propofol, a general anesthetic, and lidocaine, a local anesthetic) have been found to reduce tumor proliferation and inflammation. Lidocaine can be used systemically in small doses, even by transdermal absorption.

### Source 8 — Thinking Outside the Box – Cancer Treatments

Ray Peat · Interview · 2014

> **Andrew Murray:** 'Cause the fundamental here is basically mopping up electrons?
>
> **Ray Peat:** Yeah.
>
> **Andrew Murray:** So let me ask you this: The reactive oxygen species are a group of molecules governed electrically. The anti-oxidant system versus the reactive oxygen species system, in terms of inflammation and what free radicals, as I've understood free radical damage to be a result of free radical liberation that isn't mopped up by anti-oxidants. Is it that free radicals, I almost think of free radicals now, as being a little bit more beneficial than anti-oxidants because they....
>
> **Ray Peat:** That's Watson's interpretation but I think that shows his 50 years as a reductionist when he comes out of the static mechanical view of genetics and looks at the metabolism of the cell, he tends to over-concretise. The anti-oxidant system is doing good stuff and defending against toxic free radicals but the oxidative normal functions involving ascorbic acid or dehydro-ascorbate and Vitamin E, and the sulphydryl balancing system, those are able to control the system that he suggests the toxic free radicals would be doing. So you can get both the good defensive process against free radicals and the limiting of the production of more free radicals without resorting to one of the toxic chemicals that he's suggesting.

### Source 9 — One Radio Network: Ray Peat with Patrick Timpone — October 18, 2021

Ray Peat · Interview · Oct 18, 2021

> **Ray Peat:** Yeah, to an extent. The free radical theory of aging has a lot to it. But the faster you run your machinery, if all the nutrients to do it are present, then you produce less of those toxic-free radicals.
>
> **Patrick Timpone:** The faster we're running the machine. So the machinery you're talking, speaking of the metabolism, can you explain to us what that is really? Is it the whole energetics of the body just moving?
>
> **Ray Peat:** Yeah, if you think of oxygen as the end point, everything tends to fall towards the atoms of oxygen. So if you remove oxygen from the system, all of those electrons that were flowing rapidly towards oxygen, creating a little bit of water and oxygen, carbon dioxide, those electrons have no place to go, and they are what creates the free radical damage. So the rate of age in theory 100 years ago was popular, saying that if you could slow your oxygen consumption, you wouldn't age so fast, but exactly the opposite happens.
>
> **Patrick Timpone:** So the aging is caused by...
>
> **Ray Peat:** A breakdown of order, and the faster you run electrons through the system, the tighter the ordering is.

### Source 10 — Endotoxin, Free Radicals, and Inflammation — KMUD July 2009

Ray Peat · Interview · 2009 · http://www.l-i-g-h-t.com/files/herb-doctors-bowel-endotoxinnew.mp4

> **Ray Peat:** Since the polyunsaturated fats are the main material that causes sort of an explosion of free radical once the process starts with endotoxin and nitric oxide, simply minimizing those in the diet is a basic way to defend yourself. Essentially for hundred years there have been studies showing that a fat-free diet, if you give the required nutrients, extend lifespan and reduces cancers and other degenerative diseases. A 1927 study showed that there was no spontaneous cancer in rats on a fat-free diet. That have been repeated thousand of times in different ways but there are roughly a hundred studies that showed the tremendously beneficial effects of even a short-term deficiency so-called of the unsaturated fats. When a rat is made deficient in, according to the way they define the deficiency, they simply don't feed them polyunsaturated fats, but give them purified nutrients; those animals can stand tremendous physical trauma that would kill a rat on a normal diet - they can be given cobra venom and survive whereas a normal rat doesn't; toxins that produce diabetes in normal rats, does't hurt the so-called deficient rats. Basically, any kind of abuse that they can think of, the fatty acid deficient rats are much, much more able to tolerate and survive without harm.

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