Type

Blood

Part of

Nutritional health

Part of

Nutritional health

Blood biomarker

Part of

Nutritional health

Total Antioxidant Status (TAS)

Total antioxidant status (TAS) is a measure of the collective effect of all antioxidants in the body which combat the effects of harmful free radicals.

Total Antioxidant Status (TAS)

Normal range

> 1.3 mmol/L

Normal range

> 1.3 mmol/L

Normal range

Total Antioxidant Status (TAS)

Total antioxidant status (TAS) is a measure of the collective effect of all antioxidants in the body which combat the effects of harmful free radicals.

Total Antioxidant Status (TAS)

Normal range

> 1.3 mmol/L

Normal range

> 1.3 mmol/L

Normal range

Total Antioxidant Status (TAS)

Total antioxidant status (TAS) is a measure of the collective effect of all antioxidants in the body which combat the effects of harmful free radicals.

Total Antioxidant Status (TAS)

Normal range

> 1.3 mmol/L

Normal range

> 1.3 mmol/L

Normal range

Total Antioxidant Status (TAS)

Dr. Thiviya Sivakanthan

MBBS

Your Body’s Defence Against Oxidative Stress

Every second, your body is under attack by unstable molecules called free radicals - tiny agents of chaos that can damage your cells, accelerate ageing, and increase your risk of chronic disease. This is known as oxidative stress. Fortunately, your body fights back with antioxidants, and Total Antioxidant Status (TAS) is the scorecard of how well it’s doing.
TAS is like a shield protecting your cells, a composite measure of all the antioxidants - both natural and dietary - circulating in your blood. When your TAS is strong, your body can stay resilient and healthy. But when it’s low, you’re more vulnerable to inflammation, fatigue, and long-term health risks.

Get tested

When Your Antioxidant Defences Are Down

Discover the signs of low TAS and how oxidative stress may be silently affecting your energy, immunity, and long-term health.

What Fuels Your TAS?

Explore the vitamins, nutrients, and habits that power up your antioxidant system—and what might be quietly depleting it.

Can You Boost Your Antioxidant Defences?

Learn how to safely support your TAS through evidence-based lifestyle changes without falling for common supplement traps.

Understanding Your Results

Decode your TAS score and what it reveals about your current ability to fight oxidative stress.

When Your Antioxidant Defences Are Down

Low TAS is like having a fire alarm with no batteries - your body is vulnerable to damage, and you might not even realise it.
Oxidative stress happens when free radicals overwhelm your body’s antioxidant defences. These unstable molecules can damage DNA, proteins, and lipids, triggering inflammation and cellular dysfunction. Over time, this contributes to the development of heart disease, type 2 diabetes, neurodegenerative disorders (like Alzheimer’s), and even cancer.

You may not feel low TAS in the same way you’d feel a fever or pain, but signs like persistent fatigue, poor recovery after exercise, premature skin ageing, or brain fog can be subtle indicators that your antioxidant system isn’t coping.

In contrast, an excessively high TAS - usually due to excessive antioxidant supplements - can interfere with your body’s natural defences. Antioxidants work best in balance; too many can blunt the benefits of healthy stressors like exercise or immune responses. It’s about supporting your body, not overwhelming it.

When Your Antioxidant Defences Are Down

What Fuels Your TAS?

Your TAS isn’t about one single vitamin - it’s the sum total of your antioxidant army. Here’s what makes or breaks your defences:

Dietary antioxidants: This is the biggest contributor. Foods rich in vitamins C and E, beta-carotene, selenium, zinc, and plant-based polyphenols (found in colourful fruits, vegetables, green tea, and dark chocolate) help bolster your antioxidant capacity.
Lifestyle habits: Regular exercise, quality sleep, and stress management all strengthen antioxidant systems. But extremes - like overtraining, smoking, or poor diet—can deplete them.
Environmental exposures: Air pollution, UV radiation, alcohol, and processed foods increase oxidative load. It’s like adding more weight to the system without extra support.
Underlying conditions: Chronic illnesses such as diabetes, obesity, and autoimmune diseases are associated with increased oxidative stress and may reduce TAS.
Ageing: As you age, your body’s natural production of antioxidants can decline, making diet and lifestyle even more important.

Think of TAS like your body’s financial reserve: the more demands you place on it, the more you need to deposit with good nutrition and recovery.

What Fuels Your TAS?

Your TAS isn’t about one single vitamin - it’s the sum total of your antioxidant army. Here’s what makes or breaks your defences:

Dietary antioxidants: This is the biggest contributor. Foods rich in vitamins C and E, beta-carotene, selenium, zinc, and plant-based polyphenols (found in colourful fruits, vegetables, green tea, and dark chocolate) help bolster your antioxidant capacity.
Lifestyle habits: Regular exercise, quality sleep, and stress management all strengthen antioxidant systems. But extremes - like overtraining, smoking, or poor diet—can deplete them.
Environmental exposures: Air pollution, UV radiation, alcohol, and processed foods increase oxidative load. It’s like adding more weight to the system without extra support.
Underlying conditions: Chronic illnesses such as diabetes, obesity, and autoimmune diseases are associated with increased oxidative stress and may reduce TAS.
Ageing: As you age, your body’s natural production of antioxidants can decline, making diet and lifestyle even more important.

Think of TAS like your body’s financial reserve: the more demands you place on it, the more you need to deposit with good nutrition and recovery.

What Fuels Your TAS?

Your TAS isn’t about one single vitamin - it’s the sum total of your antioxidant army. Here’s what makes or breaks your defences:

Dietary antioxidants: This is the biggest contributor. Foods rich in vitamins C and E, beta-carotene, selenium, zinc, and plant-based polyphenols (found in colourful fruits, vegetables, green tea, and dark chocolate) help bolster your antioxidant capacity.
Lifestyle habits: Regular exercise, quality sleep, and stress management all strengthen antioxidant systems. But extremes - like overtraining, smoking, or poor diet—can deplete them.
Environmental exposures: Air pollution, UV radiation, alcohol, and processed foods increase oxidative load. It’s like adding more weight to the system without extra support.
Underlying conditions: Chronic illnesses such as diabetes, obesity, and autoimmune diseases are associated with increased oxidative stress and may reduce TAS.
Ageing: As you age, your body’s natural production of antioxidants can decline, making diet and lifestyle even more important.

Think of TAS like your body’s financial reserve: the more demands you place on it, the more you need to deposit with good nutrition and recovery.

Can You Boost Your Antioxidant Defences?

Yes - but with balance and evidence-based choices.

Prioritise food, not pills: Whole foods provide a synergistic blend of antioxidants that supplements can’t match. Eat the rainbow—deep greens, reds, oranges, and purples are your allies.
Don’t over-supplement: High doses of antioxidant supplements (like vitamin E or beta-carotene) haven’t consistently shown benefits and may even be harmful—particularly in smokers, people with a history of lung cancer, and those with cardiovascular disease. In some studies, high-dose beta-carotene increased the risk of lung cancer in smokers, and excessive vitamin E has been linked to a higher risk of hemorrhagic stroke and prostate cancer.
Stay active: Exercise generates short bursts of oxidative stress, which actually trains your body to respond better. It's like a workout for your antioxidant system.
Reduce oxidative load: Minimise exposure to tobacco smoke, processed foods, excessive alcohol, and environmental toxins where possible.

Supporting your TAS is about smart, consistent choices - not quick fixes.

Can You Boost Your Antioxidant Defences?

Yes - but with balance and evidence-based choices.

Prioritise food, not pills: Whole foods provide a synergistic blend of antioxidants that supplements can’t match. Eat the rainbow—deep greens, reds, oranges, and purples are your allies.
Don’t over-supplement: High doses of antioxidant supplements (like vitamin E or beta-carotene) haven’t consistently shown benefits and may even be harmful—particularly in smokers, people with a history of lung cancer, and those with cardiovascular disease. In some studies, high-dose beta-carotene increased the risk of lung cancer in smokers, and excessive vitamin E has been linked to a higher risk of hemorrhagic stroke and prostate cancer.
Stay active: Exercise generates short bursts of oxidative stress, which actually trains your body to respond better. It's like a workout for your antioxidant system.
Reduce oxidative load: Minimise exposure to tobacco smoke, processed foods, excessive alcohol, and environmental toxins where possible.

Supporting your TAS is about smart, consistent choices - not quick fixes.

Can You Boost Your Antioxidant Defences?

Yes - but with balance and evidence-based choices.

Prioritise food, not pills: Whole foods provide a synergistic blend of antioxidants that supplements can’t match. Eat the rainbow—deep greens, reds, oranges, and purples are your allies.
Don’t over-supplement: High doses of antioxidant supplements (like vitamin E or beta-carotene) haven’t consistently shown benefits and may even be harmful—particularly in smokers, people with a history of lung cancer, and those with cardiovascular disease. In some studies, high-dose beta-carotene increased the risk of lung cancer in smokers, and excessive vitamin E has been linked to a higher risk of hemorrhagic stroke and prostate cancer.
Stay active: Exercise generates short bursts of oxidative stress, which actually trains your body to respond better. It's like a workout for your antioxidant system.
Reduce oxidative load: Minimise exposure to tobacco smoke, processed foods, excessive alcohol, and environmental toxins where possible.

Supporting your TAS is about smart, consistent choices - not quick fixes.

Get started

Understanding Your Results

Total Antioxidant Status (TAS) is measured via a blood test and reflects your body's overall ability to neutralise oxidative stress. It’s like a real-time snapshot of your internal defence system.

TAS Levels

Normal: > 1.3 mmol/L
Low: < 1.3 mmol/L

Why Context Matters

TAS should always be interpreted alongside:

Symptoms (e.g. fatigue, frequent illness, poor recovery)
Dietary patterns
Other relevant markers like vitamin C, E, selenium, and zinc
Inflammatory indicators

It’s not a diagnostic test, but it can act as a useful early warning sign that your body may be under oxidative pressure - and in need of better nourishment or recovery strategies.

If your TAS is low, consider it your body’s way of asking for more support. A healthcare professional or registered nutritionist can help identify root causes and guide personalised interventions.

Understanding Your Results

Total Antioxidant Status (TAS) is measured via a blood test and reflects your body's overall ability to neutralise oxidative stress. It’s like a real-time snapshot of your internal defence system.

TAS Levels

Normal: > 1.3 mmol/L
Low: < 1.3 mmol/L

Why Context Matters

TAS should always be interpreted alongside:

Symptoms (e.g. fatigue, frequent illness, poor recovery)
Dietary patterns
Other relevant markers like vitamin C, E, selenium, and zinc
Inflammatory indicators

It’s not a diagnostic test, but it can act as a useful early warning sign that your body may be under oxidative pressure - and in need of better nourishment or recovery strategies.

If your TAS is low, consider it your body’s way of asking for more support. A healthcare professional or registered nutritionist can help identify root causes and guide personalised interventions.

Understanding Your Results

Total Antioxidant Status (TAS) is measured via a blood test and reflects your body's overall ability to neutralise oxidative stress. It’s like a real-time snapshot of your internal defence system.

TAS Levels

Normal: > 1.3 mmol/L
Low: < 1.3 mmol/L

Why Context Matters

TAS should always be interpreted alongside:

Symptoms (e.g. fatigue, frequent illness, poor recovery)
Dietary patterns
Other relevant markers like vitamin C, E, selenium, and zinc
Inflammatory indicators

It’s not a diagnostic test, but it can act as a useful early warning sign that your body may be under oxidative pressure - and in need of better nourishment or recovery strategies.

If your TAS is low, consider it your body’s way of asking for more support. A healthcare professional or registered nutritionist can help identify root causes and guide personalised interventions.

The Takeaway

Total Antioxidant Status gives you valuable insight into how well your body is coping with oxidative stress - the daily wear and tear that can accelerate ageing and chronic disease.
If you’re often tired, have dull skin, get frequent colds, or struggle to recover from stress or training, your TAS might be worth checking.

But don’t rush for the supplements - start with food, movement, sleep, and stress reduction. These habits power up your antioxidant reserves the natural way.
A balanced TAS means your body is better equipped to protect itself, repair damage, and help you feel and function at your best - now and for the long haul.

The Takeaway

References

Halliwell B, Gutteridge JMC. Free Radicals in Biology and Medicine. Oxford University Press, 2015.
Ames BN, Shigenaga MK, Hagen TM. Oxidants, antioxidants, and the degenerative diseases of aging. Proc Natl Acad Sci U S A. 1993;90(17):7915–7922.
National Institute for Health and Care Excellence (NICE). Nutritional assessment guidelines. 2021.
NHS UK. Antioxidants and your health

References

Halliwell B, Gutteridge JMC. Free Radicals in Biology and Medicine. Oxford University Press, 2015.
Ames BN, Shigenaga MK, Hagen TM. Oxidants, antioxidants, and the degenerative diseases of aging. Proc Natl Acad Sci U S A. 1993;90(17):7915–7922.
National Institute for Health and Care Excellence (NICE). Nutritional assessment guidelines. 2021.
NHS UK. Antioxidants and your health

References

Halliwell B, Gutteridge JMC. Free Radicals in Biology and Medicine. Oxford University Press, 2015.
Ames BN, Shigenaga MK, Hagen TM. Oxidants, antioxidants, and the degenerative diseases of aging. Proc Natl Acad Sci U S A. 1993;90(17):7915–7922.
National Institute for Health and Care Excellence (NICE). Nutritional assessment guidelines. 2021.
NHS UK. Antioxidants and your health