Why Your Body Produces Free Radicals Every Day and Why They Become Dangerous in 2026

By Dr. Dwight Prentice

Editor’s Note: Free radicals are often talked about as though they are poisonous substances that should never exist inside the body. That is not correct. Your body naturally produces free radicals every day, and some of them actually help you stay alive.

They help immune cells fight germs. They help cells communicate. They are produced when your cells make energy. Even exercise temporarily increases them.

The problem is not simply having free radicals.

The problem begins when your body produces more of these reactive molecules than it can safely control, repair or remove.

That imbalance is called oxidative stress—which simply means your cells are experiencing more chemical damage than their protective systems can comfortably handle.

Important: Free radicals and oxidative stress are involved in many diseases, but they are not the single cause of every illness. Persistent fatigue, weakness, chest pain, breathlessness, memory problems, swelling, unexplained weight loss or other ongoing symptoms require proper medical evaluation. Do not assume that taking antioxidants will automatically treat the underlying problem.

Introduction: Free Radicals Are Part of Normal Life

Your body is carrying out millions of chemical reactions every second.

You breathe.

You digest food.

Your muscles contract.

Your brain sends messages.

Your liver processes substances.

Your immune system watches for germs.

Your cells produce energy.

During many of these normal activities, reactive molecules are produced.

Some of these are called free radicals.

A free radical is simply a very unstable molecule that reacts easily with things around it.

Imagine a tiny spark.

A spark can be useful when controlled.

But if too many sparks are allowed to spread without control, they can start damaging everything around them.

That is a simple way to understand free radicals.

In Tuesday’s pillar article, Oxidative Stress Explained: The Silent Cellular Damage Behind Most Chronic Diseases in 2026, we explained what happens when these reactive molecules become excessive.

Today, we are going one step backward.

Why does the body produce free radicals at all?

What Exactly Is a Free Radical?

Atoms and molecules contain tiny particles called electrons.

You do not need to understand chemistry to understand the important part.

A free radical has an electron arrangement that makes it unstable.

Because it is unstable, it may react quickly with nearby molecules.

Those reactions may involve:

• Cell membranes
• Proteins
• DNA
• Mitochondria
• Fats inside cells

Some free radicals contain oxygen.

You may also hear the term reactive oxygen species, or ROS.

Reactive oxygen species simply means oxygen-containing molecules that react easily inside the body.

Some ROS are free radicals. Others are not technically free radicals but can still contribute to oxidative reactions.

The important idea is simple:

these molecules are highly reactive, so the body must keep them under control.

1. Your Mitochondria Naturally Produce Reactive Molecules

Mitochondria are the tiny energy-producing structures inside your cells.

They use nutrients and oxygen to help produce ATP.

ATP is the usable energy your cells need to work.

During this energy-making process, a small amount of oxygen may be converted into reactive oxygen species.

This is normal.

A healthy cell has systems that control most of these reactive molecules before they cause serious damage.

Problems may develop when mitochondria become damaged, when energy demand becomes excessive or when the body is under long-term metabolic stress.

Damaged mitochondria may produce reactive molecules less efficiently.

This can create a cycle:

Mitochondrial damage → more reactive molecules → more mitochondrial stress

This is why our previous Mitochondria pillar spent so much time discussing mitochondrial quality, exercise, nutrition and mitophagy—the process that helps cells remove badly damaged mitochondria.

2. Your Immune System Uses Free Radicals as Weapons

One of the most important uses of reactive molecules happens inside your immune system.

White blood cells are the body’s defense cells.

Some white blood cells can surround and swallow bacteria.

Once the germ is trapped, the immune cell may produce powerful reactive molecules to help destroy it.

This process is sometimes called an oxidative burst.

That phrase simply means the immune cell suddenly produces a burst of reactive molecules to kill a germ.

This is extremely useful.

If your body could not generate these defensive molecules properly, fighting certain infections would become much harder.

This is why trying to eliminate every free radical would actually be harmful.

Your body needs some of them.

3. Free Radicals Help Cells Communicate

Cells are constantly sending messages to one another.

Some reactive oxygen species act as signaling molecules.

A signaling molecule is simply a chemical messenger.

These signals can help regulate:

• Cell growth
• Immune responses
• Blood-vessel function
• Adaptation to exercise
• Repair processes
• Removal of badly damaged cells

The important point is that the amount matters.

A small controlled signal may be useful.

Too much of the same reactive molecule may become damaging.

This is one of the recurring lessons in biology:

more is not always better, and less is not always better. Balance matters.

4. Exercise Temporarily Produces More Reactive Molecules

When you exercise, your muscles use more oxygen and produce more energy.

This temporarily increases some reactive molecules.

At first, that may sound harmful.

But sensible exercise usually makes the body stronger rather than weaker.

Why?

Because the temporary increase acts like a training signal.

Your cells respond by improving some of their own protective systems.

This type of useful, controlled stress is sometimes called hormesis.

Hormesis simply means a small challenge that encourages the body to become better prepared for future challenges.

Think about strength training.

You challenge the muscle.

The muscle responds by becoming stronger during recovery.

Something similar happens with cellular protection.

This is one reason very large doses of antioxidant supplements around exercise are not automatically helpful. In some situations, they may interfere with signals that help the body adapt.

5. Inflammation Naturally Produces Reactive Molecules

Inflammation is the body’s response to injury, infection or danger.

During short-term inflammation, immune cells enter the affected area and release substances that help control the problem.

Reactive molecules may be part of that response.

This is useful when the inflammation is temporary.

The problem begins when inflammation stays active for weeks, months or years.

Then the body may continue producing reactive molecules even though the original emergency has passed.

Healthy tissue may begin experiencing unnecessary stress.

This creates the cycle we discussed in Tuesday’s pillar article:

Chronic inflammation → more reactive molecules → cellular damage → more inflammation

This relationship also connects with Why Chronic Inflammation Can Exhaust Your Immune System in 2026.

6. Your Liver Can Produce Reactive Molecules While Processing Substances

Your liver is one of the body’s major chemical-processing organs.

It helps process:

• Medicines
• Alcohol
• Hormones
• Nutrients
• Environmental chemicals
• Waste products

During some of these chemical reactions, reactive molecules can be formed.

Usually the liver has protective systems that keep this under control.

But repeated exposure to heavy alcohol use, certain toxins, excess liver fat or some medications may increase oxidative pressure.

This is another reason the liver needs protection rather than constant “detoxing.”

The body already has detoxification systems.

Your job is to avoid overwhelming them.

7. High Blood Sugar Can Increase Free-Radical Production

Glucose is normal.

Your body needs it for energy.

But glucose that remains too high for too long creates problems.

Persistently high blood sugar can increase reactive molecules through several pathways.

It may also contribute to glycation.

Glycation simply means sugar sticking to proteins or fats and changing the way they work.

Over time, these changes can contribute to damage in:

• Blood vessels
• Kidneys
• Nerves
• Eyes
• Heart

This is one reason blood-sugar control matters even when a person does not immediately feel sick.

Damage may be developing quietly.

8. Smoking Adds a Huge External Free-Radical Load

Not all reactive molecules come from your own metabolism.

Cigarette smoke contains enormous numbers of reactive chemicals.

Smoking also stimulates inflammation and damages blood vessels.

This creates repeated oxidative pressure on:

• The lungs
• The heart
• Blood vessels
• DNA
• The skin
• Immune cells

This is why antioxidants cannot make smoking safe.

You cannot continuously pour smoke into the body and expect vitamins to cancel the damage.

Removing the harmful exposure is far more powerful.

9. Air Pollution Can Add Oxidative Pressure

Air pollution contains tiny particles and chemicals that may enter the lungs.

Some particles are extremely small and can reach deep into lung tissue.

Exposure may trigger inflammation and increase oxidative stress.

This becomes particularly important for people living or working near:

• Heavy traffic
• Industrial pollution
• Open burning
• Smoke-producing workplaces
• Indoor cooking smoke without good ventilation

You cannot always control the outdoor environment.

But where possible, improving ventilation and reducing avoidable smoke exposure may help reduce unnecessary respiratory stress.

10. Sunlight Can Produce Reactive Molecules in the Skin

Sunlight is important.

But too much ultraviolet radiation can damage skin cells.

Ultraviolet radiation, or UV radiation, is invisible energy from sunlight that can affect skin and DNA.

UV exposure can increase reactive molecules inside skin cells.

Repeated excessive exposure may contribute to:

• Premature skin aging
• Wrinkles
• Uneven pigmentation
• DNA damage
• Skin cancer risk

The message is not to fear sunlight.

It is to avoid repeated burning and excessive exposure.

11. Alcohol Can Increase Oxidative Stress

The body must process alcohol after you drink it.

During this process, harmful intermediate chemicals and reactive molecules may be formed.

Heavy or frequent alcohol use may place pressure on:

• The liver
• The brain
• The heart
• The digestive system
• Sleep
• Nutritional status

This does not mean one drink instantly destroys your mitochondria.

Again, amount and frequency matter.

The greatest concern is repeated excessive exposure.

12. Poor Sleep Can Make Oxidative Balance Worse

Sleep is one of the body’s major recovery periods.

During sleep, many systems involved in metabolism, repair, immune regulation and brain function are reorganized.

Repeated sleep deprivation can increase inflammatory pressure and interfere with glucose control.

These changes may increase oxidative stress.

This is why chronic poor sleep is much more than feeling tired the following morning.

It affects the environment inside your cells.

If you regularly snore loudly, stop breathing during sleep or remain exhausted despite spending enough time in bed, you may need evaluation for sleep apnea.

Sleep apnea means breathing repeatedly becomes blocked or stops while you sleep.

13. Psychological Stress Can Affect the Body Too

Stress begins in the brain, but it does not stay there.

When you experience repeated psychological stress, the body releases stress hormones such as cortisol and adrenaline.

These hormones are useful during short-term emergencies.

But long-term stress can affect:

• Sleep
• Blood pressure
• Blood sugar
• Food choices
• Immune regulation
• Physical activity

Through these pathways, chronic stress may contribute indirectly to oxidative pressure.

This is why stress management should be treated as part of physical healthcare, not simply emotional comfort.

14. Your Body Has Its Own Antioxidant Defense System

Your body does not wait for antioxidant supplements to protect itself.

It already makes several powerful antioxidant enzymes.

An enzyme is simply a protein that helps a chemical reaction happen efficiently.

Important antioxidant systems include substances such as:

• Glutathione
• Superoxide dismutase
• Catalase

The names sound complicated.

The job is simple.

They help control reactive molecules before those molecules cause excessive damage.

Your body needs nutrients such as selenium, copper, zinc and other dietary components to help some of these systems work properly.

This is why healthy nutrition supports antioxidant defense rather than replacing it.

15. Food Gives Your Body Extra Protection

Plant foods contain vitamins and many natural compounds that help support cellular protection.

These include substances found in:

• Leafy vegetables
• Tomatoes
• Carrots
• Peppers
• Berries
• Citrus fruits
• Beans
• Nuts
• Seeds
• Herbs
• Spices

You do not need to memorize the names of every antioxidant compound.

A simpler rule works:

eat a wide variety of natural foods, especially plants of different colours.

Different colours often mean different protective plant compounds.

When Do Free Radicals Become Dangerous?

Free radicals become dangerous when their production repeatedly becomes greater than the body’s ability to control and repair the damage.

This may happen when several pressures occur together:

• Smoking
• High blood sugar
• Chronic inflammation
• Heavy alcohol use
• Poor sleep
• Severe pollution exposure
• Poor nutrition
• Excessive ultraviolet exposure
• Certain illnesses
• Damaged mitochondria

This is oxidative stress.

It does not mean every cell is suddenly being destroyed.

It means the balance has moved too far toward damage.

The Free-Radical Chain Reaction

One reason free radicals can become troublesome is that one reaction may trigger another.

Imagine one unstable molecule damages part of a cell membrane.

The damaged molecule may then become reactive itself.

It can attack another nearby molecule.

Then another.

This is sometimes called a chain reaction.

Antioxidant systems help interrupt these reactions before they spread too far.

This is why protection depends on balance, repair and control rather than trying to prevent every oxidative reaction from ever happening.

How To Keep Free Radicals in a Healthier Balance

You cannot eliminate every free radical.

You should not try.

Instead, reduce unnecessary production while strengthening your body’s natural protective systems.

• Do not smoke: Tobacco adds a large amount of avoidable oxidative pressure.
• Control blood sugar: Persistent high glucose increases cellular stress.
• Exercise regularly: Sensible exercise trains your natural antioxidant defenses.
• Eat colourful whole foods: Give your body a wide variety of nutrients and plant compounds.
• Protect sleep: Recovery is essential for metabolic and cellular balance.
• Limit excessive alcohol: Reduce unnecessary pressure on the liver and other organs.
• Manage chronic inflammation: Find and address the underlying source.
• Protect yourself from excessive sun exposure: Especially repeated sunburn.
• Reduce avoidable smoke and pollution exposure: Improve ventilation where possible.
• Protect mitochondrial health: Stay active, preserve muscle and maintain metabolic health.

Why More Antioxidants Are Not Always Better

Once people understand oxidative stress, the natural reaction is often:

“Then I should take as many antioxidants as possible.”

Not necessarily.

Remember that reactive molecules also have useful jobs.

They help immune cells kill germs.

They help cells communicate.

They help your body adapt to exercise.

Taking very large amounts of antioxidant supplements may sometimes interfere with these normal signals.

Some high-dose supplements may also interact with medication or become harmful themselves.

The safest foundation is food, movement, sleep and control of known risk factors.

Supplements may have a role when there is a genuine need.

They should not replace the foundation.

When Symptoms Need Proper Medical Investigation

There is no single symptom that proves you have excessive free radicals.

Fatigue does not automatically mean oxidative stress.

Neither does pain, brain fog or poor sleep.

Seek medical assessment if you experience:

• Persistent or severe fatigue
• Unexplained weight loss
• Chest pain
• Breathlessness
• Progressive weakness
• New swelling
• Persistent fever
• Memory or neurological changes
• Repeated infections
• Poor wound healing

The goal is to identify the actual cause rather than trying to treat an invisible idea with random antioxidant products.

Did You Know?

Your body deliberately produces reactive molecules every day. White blood cells use them to destroy germs, and exercise uses them as signals that encourage cells to adapt. Free radicals become a problem when their production remains too high or when the body’s protective and repair systems can no longer keep up.

Dr. Prentice’s Preventive Prescription

1. Do not fear every free radical: Your body needs some reactive molecules for immunity, communication and adaptation.
2. Reduce unnecessary production: Stop smoking, control high blood sugar, limit excessive alcohol and reduce avoidable pollution exposure.
3. Strengthen natural protection: Exercise regularly, eat varied whole foods and protect your sleep.
4. Avoid antioxidant excess: More supplements do not automatically mean more protection.
5. Look for the real problem: Persistent symptoms need proper investigation rather than being labelled oxidative stress without evidence.

The SoftLifeMindset Principle

Your body was not designed to live without stress.

It was designed to handle reasonable stress, respond to it and recover.

Free radicals are part of that system.

The goal is not to eliminate every spark. The goal is to stop the sparks from becoming a fire.

Final Thoughts

Free radicals are not foreign enemies invading your body.

Your body produces them naturally.

Your mitochondria produce some during energy production.

Your immune cells use them to kill germs.

Your muscles generate more during exercise.

Your cells use them as chemical messages.

In the correct amount, they are part of normal life.

The danger begins when the balance changes.

Smoking adds more reactive chemicals.

High blood sugar increases metabolic pressure.

Chronic inflammation keeps producing reactive molecules.

Poor sleep interferes with recovery.

Heavy alcohol use places additional pressure on the liver.

Damaged mitochondria may generate more oxidative stress.

Eventually, the body's protective and repair systems may struggle to keep up.

That is when normal oxidation begins turning into harmful oxidative stress.

You do not need to become frightened of oxygen, sunlight, exercise or food.

You need balance.

Remove unnecessary sources of damage.

Support your natural defenses.

Feed your body well.

Move regularly.

Protect your sleep.

Control blood sugar.

Stop smoking.

Allow your body to recover.

That is much more powerful than trying to swallow enough supplements to eliminate every free radical.

Ask Dwight

If persistent fatigue, poor blood-sugar control, chronic inflammation, slow recovery, high blood pressure or other health concerns are affecting you, do not simply assume you need more antioxidants. Ask Dwight and begin taking a structured preventive approach to identifying and reducing the real sources of unnecessary cellular stress.

Ask Dwight

References

• Reactive Oxygen Species in Cell Signaling and Oxidative Stress
• Reactive Oxygen Species: Sources, Cellular Signaling and Biological Effects
• Reactive Oxygen Species, Oxidative Stress and Antioxidant Defense
• Reactive Oxygen Species in Immunity and Inflammation
• Exercise, Reactive Oxygen Species and Cellular Adaptation
• World Health Organization: Tobacco
• World Health Organization: Air Pollution
• World Health Organization: Ultraviolet Radiation

Life is simple there's no need to complicate it! SLMindset.

Medical Disclaimer: This article is intended for general health education and does not replace individualized medical advice, diagnosis or treatment from a qualified healthcare professional. Persistent, severe or concerning symptoms should be properly evaluated.