Thread by @ck_eternity_

The idea that free radicals = bad and antioxidants = good is a major oversimplification

When we talk about redox state it's not just about maintaining as little oxidation as possible, but rather keeping an appropriate balance in place between reduction and oxidation

(thread)

Chemistry 101:

Put simply, oxidation refers to any chemical reaction involving the loss of an electron, when something is oxidized it just means that one of its electrons is transferred to another molecule

Reduction is the inverse of this, a molecule or atom gaining an electron from another molecule or atom

As you can see, it's impossible for reduction to occur without oxidation, and vice versa, hence the shorthand "redox" refers to this category of reactions

Now when we look at how this occurs in the body free radical production is an excellent example

A "free radical" is any molecule with an unpaired electron, which makes it highly reactive and unstable, it will neutralize itself by reacting with the first available electron donor

The most common source of free radicals in the body is oxidative phosphorylation (the main ATP synthesis pathway in mitochondria), which involves an electron circuit that sometimes cross-reacts with nearby oxygen or water molecules creating "reactive oxygen species" as a result

Reactive oxygen species (ROS) refers to free radicals containing oxygen, while the less common reactive nitrogen species (RNS) refers to nitrogen containing free radicals

RNS are created primarily as byproducts of the metabolism of nitric oxide, which regulates blood flow

These free radicals are neutralized by antioxidants, which act as electron donors, oxidizing themselves in order to reduce free radicals before they have the chance to react with nearby protein, lipids, or DNA instead

Antioxidants are then recycled back into their reduced form

This process maintains the balance referred to broadly as the "redox state"

It's true that too much oxidation can be harmful, playing a role in the pathology of cancer, heart disease, and aging

I've discussed this frequently in the context of iron, light environment, etc

But this isn't the whole story, oxidation can also be beneficial, and some antioxidants can paradoxically increase the risk of these same diseases

As an example, ROS are used as signaling molecules between the mitochondria and cell nucleus, altering gene transcription

This ROS signaling is what allows light to dynamically alter gene expression and regulate circadian rhythm (via genes like CLOCK, Bmal1, etc)

This is an example of how changes like these can play out during infrared light exposure via sunlight or therapy:

If we block this signaling we may impair these processes and potentially alter circadian rhythm or other aspects of cell metabolism

The interaction between ROS and muscle growth is another example, certain antioxidants have been shown to slow hypertrophy
ncbi.nlm.nih.gov/pmc/articles/P…

The question is nutrient antioxidants is also complex

While vitamin C is an very beneficial antioxidant, it also paradoxically increases iron oxidation, so it may not be so beneficial in all cases or at very high doses
ncbi.nlm.nih.gov/pmc/articles/P…

The takeaway from all this is that in many cases oxidative stress is actually a hormetic response and provides benefit

Things like living at high altitude, exercise, sunlight exposure, cold thermogenesis, saunas, etc, all operate via this mechanism

If you want to balance redox state apply oxidative stress via these activities, while also utilizing appropriate antioxidants

In particular, plant compounds are highly beneficial here, especially those in the flavonoid or quinone classes (polyphenols in general are excellent)

Focus on food sources for these phytochemicals, as well as most nutrients

There are definitely cases where nutrient supplements are necessary or beneficial, but especially when it comes to antioxidants like retinol, vitamin C, and vitamin E, food sources are king

Lastly, it's important to avoid things that create imbalances in this redox state

Some like isolated blue light disrupt circadian signaling, while others like iron accumulation or alcohol consumption quickly outpace any hormetic benefits they may provide at low doses