Your Guide to the Top Antioxidants

Life Extension europe: Person wearing orange sweater and gre pants, carrying a wooden tray with antioxidant ingredients. Lemon, garlic, tumeric.

Certain enzymes, such as glutathione peroxidase, superoxide dismutase, and catalase, play a role as antioxidants. These enzymes contain metals like selenium and zinc. 

This blog gives a rundown of some of the main antioxidants you need to know about. Here you can learn as much as possible about these powerful nutrients.

What are Antioxidants Good for?

The importance of fighting off free radicals

Free radicals molecules are missing an electron from their outer shell. That makes them unstable, so they go and steal an electron from the molecules in your skin cells, or from your blood cells, or from wherever they can.

The body generates free radicals in response to environmental insults, such as tobacco smoke, ultraviolet rays, and air pollution, but they are also a natural byproduct of normal processes in cells.

Too many free radicals create oxidative stress — cells get damaged and even die. When your body is experiencing oxidative stress, we find signs of aging and disease.

The body's own defence mechanism

Thankfully our body has its defense mechanism; antioxidants. When free radicals don’t have antioxidants to keep them in check, they go wild.

An antioxidant is a general term for any compound that can counteract these unstable free radical molecules that damage DNA, cell membranes, and other parts of cells.

How Many Antioxidants are There?

There are possibly thousands of different compounds with antioxidant properties. 

Popular examples include

Additionally there are antioxidants like glutathione, coenzyme Q10, lipoic acid, flavonoids, phenols, polyphenols, phytoestrogens, and many more, most of which occur naturally in food and help prevent oxidation or protect against environmental factors.


Cysteine, a sulfur-related antioxidant, is a vital component of glutathione, a major antioxidant protecting organs like the liver, kidneys, blood cells, and lungs. (1)

Prolonged oxidative stress, often intensified by factors like drug and alcohol abuse, can deplete glutathione, leaving cells susceptible to damage. Maintaining healthy levels is essential for protecting against diseases and keeping cells healthy.  

Glutathione is a powerful molecule naturally made by your body, comprising three amino acids. It's present in every cell, acting as the main detoxifier, especially in the liver, and a potent antioxidant, safeguarding cells from damage. 

This superhero molecule boosts your immune system and neutralizes harmful free radicals, with foods like avocados being excellent sources. However, glutathione levels decrease with age, increasing vulnerability to oxidative damage. 

Adding NAC (N-acetyl-L-cysteine), a modified amino acid, can help boost your glutathione levels, fortifying your body's defenses and ensuring continued cellular health. Keep your glutathione levels up to keep your body strong and protected!

Alpha Lipoic Acid 

Lipoic acid, another sulfur-related antioxidant, stands out for scavenging both water- and fat-type radicals. (2) Studies show its effectiveness in reducing oxidative stress markers. 

Known for benefits against diabetes, lipoic acid has been used to manage diabetic neuropathy and protect eyes. It can even help prevent diabetes, demonstrating its versatility. (3-6) As we age, glutathione levels decline, influenced by genetic factors. (7,8) 

Supplemental lipoic acid not only reverses this decline, safeguarding the heart and brain, but also reactivates aging genes. (7-9) Combined with L-carnitine, lipoic acid forms a potent antidote to age-related antioxidant and energy loss, synergistically enhancing mitochondrial function. (10-11)

Alpha Lipoic Acid is known as the universal antioxidant. Alpha-lipoic acid works well because it can dissolve in both fat and water, making it a potent antioxidant. The benefits of this antioxidant include:  

  • Boosting glutathione levels 
  • Providing strong antioxidant benefits 
  • Supporting the liver and nerves 
  • Helping control blood sugar 
  • Preventing LDL cholesterol damage

R-Lipoic Acid is the purest and most biologically active form of alpha-lipoic acid. Its unique structure allows it to easily cross the blood-brain barrier and reach vital organs, enhancing its potential benefits.

Ginkgo Biloba 

Ginkgo Biloba, a particularly important plant antioxidant, combats oxidative stress in the brain with its rich flavonoids and metal chelators. These enhance cellular defenses. 

It promotes neuroprotection by reducing inflammation, (12) improving circulation, preventing harmful amyloid build-up, and maintaining neurotransmitter balance. 

Crucially, it safeguards mitochondria, our cellular powerhouses, from damage. In turn it supports brain health and function (13), particularly against disorders like Alzheimer's.


Curcumin, the critical compound in turmeric, is a key antioxidant with significant anti-inflammatory effects. (14)  It actively scavenges harmful free radicals, boosts lipid protection, and enhances antioxidant defenses by activating pathways like Nrf2. 

Research highlights its ability to shield vital brain cells from oxidative stress (15-17)  and inflammation, contributing to its potential as a treatment for Alzheimer’s and other neurodegenerative disorders like Parkinson’s and Huntington’s.

Beyond its antioxidant properties, curcumin shows promise in: 

  • Reducing anxiety and depression (18)
  • Improving brain health after injuries (19-21)
  • Enhancing memory and learning (22)

This powerful component of turmeric isn't just a spice for flavor but a powerful agent for brain and overall health.


Coenzyme Q10 (CoQ10) stands out as a first-line antioxidant, crucial for reducing oxidative stress and supporting cardiovascular health. This essential nutrient plays a pivotal role in energizing cells and has shown promise in protecting against neurodegenerative diseases like Alzheimer’s and Parkinson’s. 

Clinical trials highlight its ability to lower inflammation, improve blood sugar control, and enhance liver function. The benefits extend to reducing skin wrinkles, promoting kidney health, and boosting lung function.

Traditionally available as ubiquinone, CoQ10 is now also found in the more bioavailable, absorbable form of ubiquinol, offering enhanced benefits, particularly for those with congestive heart failure.


Resveratrol is a polyphenol (type of antioxidant) compound, that is found in several plants, most notably red grapes, some berries, and Japanese knotweed.

In its free form, resveratrol has poor bioavailability. Most of the free resveratrol does not end up in the bloodstream and cannot get to the tissues where it can exert beneficial effects. The main reason is that active resveratrol is rapidly metabolized. (23-25)

It has been shown in a number of different models to promote longevity, and has been studied for improving metabolic, cardiovascular, brain, and immune health.


Astaxanthin is a carotenoid pigment with powerful antioxidant and anti-inflammatory properties. It is probably the strongest  out there. It has been recently acclaimed as a protector for the skin. (26) 

The best way to take astaxanthin is in combination with phospholipids, which makes it far more bioavailable (absorbable). It is a caroteinouid, which is present in yeast, crayfish and salmon. 

Recent research has shown that ithelps protect the heart and prevent against heart disease. (27) Astaxanthin also supports healthy glucose metabolism. (28)


Since its discovery over 50 years ago, melatonin has demonstrated itself as a functionally diverse molecule, with its antioxidant properties being amongst its most well-studied attributes. (29,30) 

In fact, melatonin has been found to possess 200% more antioxidant power than vitamin E. Melatonin is found to be superior to glutathione as well as vitamins C and E in reducing oxidative damage. (31) 

As such a potent antioxidant, melatonin plays a powerful role in fighting free-radical-related diseases — from cardiovascular disease to cancer and practically everything in between.

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