We talk a lot about antioxidants, inflammation, oxidative stress and the things we can do to support our health.
But behind many of these conversations is a fascinating cellular system that most people have probably never heard of.
It’s called Nrf2.
Nrf2 — nuclear factor erythroid 2-related factor 2, if you’d like the full scientific name — is a transcription factor. In simple terms, it’s a protein that can help switch particular genes on.
And those genes are involved in some very important jobs, including our cells’ response to oxidative stress, antioxidant defence and cellular protection.
So what does that actually mean for our health?
First, what is oxidative stress?
Our cells naturally produce molecules known as reactive oxygen species (ROS) as part of normal metabolism.
ROS aren’t automatically bad. They play roles in normal cellular signalling and can increase temporarily during activities such as exercise.
Problems can arise when the production of reactive molecules overwhelms the body’s ability to manage them.
This imbalance is known as oxidative stress.
Persistent oxidative stress can damage cellular components and is associated with ageing and numerous chronic health conditions. It is also closely connected with inflammation.
Fortunately, our bodies have sophisticated systems for responding to it.
And that’s where Nrf2 comes in.
Meet your cellular defence coordinator
Under ordinary circumstances, Nrf2 is tightly controlled inside the cell, particularly through its relationship with a regulatory protein called Keap1.
When the cell encounters certain types of stress, this relationship changes.
Nrf2 can accumulate and move into the cell nucleus — the part of the cell containing our DNA.
Once there, it interacts with regions of DNA known as antioxidant response elements (AREs) and stimulates the expression of genes involved in antioxidant and cytoprotective responses.
You could think of Nrf2 as a cellular defence coordinator.
It isn’t an antioxidant itself.
Instead, it helps coordinate some of the body’s own protective machinery when it’s needed.
Nrf2 and inflammation
This becomes particularly interesting when we look at inflammation.
Inflammation is an essential part of our defence and repair systems. We need it.
But persistent or poorly regulated inflammation is a different matter.
A 2026 review explored Nrf2 activation in inflammatory diseases including rheumatoid arthritis, inflammatory bowel disease, diabetes and periodontitis. The researchers describe Nrf2 as a central regulator of cellular antioxidant responses with an important role in modulating inflammation and protecting against oxidative damage.
This doesn’t mean that “activating Nrf2” is a treatment for inflammatory disease.
In fact, the biology is much more nuanced than that.
Nrf2 isn’t simply an ON switch
This is perhaps the most fascinating part.
A second 2026 paper describes Nrf2 as an ancient survival pathway and a potential “guardian of health”, looking at its relationship with redox signalling, chronic inflammation, ageing and disease.
The emerging picture isn’t of a system we simply want to switch on and leave running.
It’s one that needs to be appropriately regulated.
The inflammatory-disease review makes this particularly clear. While Nrf2 activation can support cytoprotective responses, sustained or dysregulated Nrf2 activity may also be problematic in certain contexts. For example, some cancer cells can exploit increased Nrf2 activity to aid their own survival and resistance to treatment.
So, once again, we’re back to a theme I return to frequently:
More isn’t necessarily better. Balance matters.
A cellular dimmer switch
One useful way to picture Nrf2 is less like a simple light switch and more like a dimmer switch — or rheostat.
Our cells are continually responding to changing conditions.
Sometimes they need to increase their protective responses. At other times, those responses need to settle again.
This ability to adapt is part of what makes the concept of cellular resilience so interesting.
And it leads us to another fascinating idea: hormesis.
Why a little stress isn’t necessarily bad
We often talk about stress as though our goal should be to eliminate it completely.
Biologically, that’s not quite how things work.
Some relatively small, temporary challenges can stimulate adaptive responses that help the body become better equipped to deal with future challenges.
Exercise is probably the easiest example.
Physical activity temporarily increases metabolic demand and the production of reactive oxygen species.
That sounds undesirable.
Yet this controlled challenge is also one of the signals that stimulates the body’s adaptive antioxidant systems.
A 2025 review examining functional foods, exercise and Nrf2 describes physical activity as a stimulus for Nrf2 signalling and the body’s endogenous antioxidant defences. It also discusses its relationship with mitochondrial function and metabolic adaptation.
Your body isn’t simply being protected from the challenge.
It’s adapting because of the challenge.
Can food influence Nrf2 too?
This is another rapidly developing area of research.
Plant foods contain thousands of biologically active compounds, and researchers are investigating how some of them interact with Nrf2 and related signalling pathways.
Compounds discussed in the research include:
- Sulforaphane, associated particularly with cruciferous vegetables
- Quercetin, found in foods including onions and apples
- Resveratrol, associated with grapes and other plant foods
- Curcumin, found in turmeric
- A wide range of other polyphenols and flavonoids
The 2026 inflammatory-disease review includes curcumin, sulforaphane and resveratrol among natural compounds that have been studied as Nrf2 activators.
Meanwhile, the 2025 review explores the potential complementary effects of antioxidant-rich functional foods and physical activity, particularly through Nrf2 and related pathways involved in oxidative stress, inflammation, energy metabolism and mitochondrial health.
Food + movement: an interesting partnership
This may be one of the most useful messages to take from the research.
We tend to divide health into separate boxes.
Nutrition goes in one.
Exercise goes in another.
Stress goes somewhere else.
Sleep has its own category.
But our cells don’t recognise those divisions.
The foods we eat and the way we move can influence overlapping biological pathways.
The 2025 review proposes that antioxidant-rich foods and regular physical activity may have complementary effects on Nrf2 signalling and metabolic health. However, the authors also highlight limitations in the existing evidence, including individual variation and the need for further clinical research into long-term outcomes.
So this isn’t a prescription to consume huge quantities of one particular “Nrf2-activating” food or supplement.
It’s a much broader—and arguably more interesting—picture.
We already have our own antioxidant defence system
When people hear the word antioxidant, they often immediately think about something we need to consume.
But the human body has its own sophisticated antioxidant systems.
Nrf2 helps regulate genes involved in those endogenous defences.
And that changes the conversation slightly.
Instead of asking only:
“How many antioxidants can I consume?”
we can also ask:
“How do my everyday choices support my body’s own ability to respond and adapt?”
A varied, plant-rich diet provides numerous bioactive compounds.
Regular physical activity provides an appropriate physiological challenge.
Adequate nutrition provides the raw materials our cells require.
Rest and recovery give the body an opportunity to repair and adapt.
None operates independently.
From immune balance to cellular resilience
Over recent weeks, I’ve been talking about the immune system and why I prefer the idea of immune regulation to indiscriminate “immune boosting”.
Nrf2 gives us another example of the same principle.
The body is full of extraordinarily sophisticated regulatory systems.
We don’t necessarily want them permanently switched to maximum.
We want them able to sense, respond, adapt and return towards balance.
And perhaps that’s one of the most useful ways to think about health itself.
Not as the complete absence of challenge.
But as resilience — the capacity to meet an appropriate challenge, respond to it and recover.
At a microscopic level, our cells are doing this every day.
And Nrf2 appears to be one fascinating part of that story.
Further reading
Nrf2 Activation in Inflammatory Diseases: A Review of Natural and Synthetic Modulators
NRF2 as a Guardian of Health: From an Ancient Survival Pathway to a Modern Therapeutic Target
