Lipid peroxidation protection
Prevents oxidative damage to cellular and organellar membranes
Glutathione Peroxidase (GPx)
Selenium-dependent antioxidant enzyme that reduces lipid peroxides and hydrogen peroxide using glutathione as cofactor
Scientific nameGlutathione peroxidase enzyme
FormulaSelenoprotein enzyme
Molecular weight80-84 kDa g/mol
CAS9013-66-5
95
absorption score
8
safety / 10
25
USD per month
5
documented interactions
Check it against something
Glutathione Peroxidase (GPx) with:
- Amylase
- Ashwagandha
- Avocado Oil
- BCAA (Branched-Chain Amino Acids)
- Beetroot Powder
- Beta-Alanine
- Bifidobacterium lactis
- Bifidobacterium longum
- Bovine Collagen
- Caffeine
- Calcium
- Calcium Bone Formula
- Calcium Carbonate
- Casein Protein
- Chicken Collagen
- Choline (Bitartrate)
- Chondroitin Sulfate
- Coconut Oil
- Collagen Peptides
- Comprehensive Immune Support Complex
- Comprehensive Multivitamin-Mineral Complex
- Creatine HCL
- Creatine Monohydrate
- D-Mannose
- DHA
- Electrolyte Blend
- EPA
- Fish Oil (EPA/DHA)
- Folate (5-MTHF)
- Ginger
- Glutathione
- Iron Fumarate
- Iron Sulfate
- Joint Mobility Formula
- Keratin
- Krill Oil
- L-Carnitine
- L-Citrulline
- Lactase
- Lactobacillus acidophilus
- Lactobacillus rhamnosus
- Lipase
- Magnesium Citrate
- Magnesium Glycinate
- Magnesium Oxide
- Marine Collagen
- Melatonin
- Modafinil
- Olive Oil Extract
- Omega-3 + Curcumin + Vitamin D Triple Anti-Inflammatory Formula
- Papain
- Protease
- Saccharomyces boulardii
- Turmeric
- Vitamin B12 (Cyanocobalamin)
- Vitamin B12 (Methylcobalamin)
- Vitamin C (Ascorbic Acid)
- Vitamin C (Sodium Ascorbate)
- Vitamin D3
- Whey Protein
- Zinc Gluconate
Nothing found
82
out of 100
Works better together
Compatible. Timing differs, so follow each supplement's own window.
What it does
mechanism and evidence for each claimEnhanced glutathione utilization
Optimizes the cellular glutathione antioxidant system
Cardiovascular protection
Protects blood vessels and heart tissue from oxidative damage
Enhanced immune function
Protects immune cells from oxidative damage during immune responses
Neurological protection
Protects brain and nervous system from oxidative stress
Others take these for the same thing
Same goal, different mechanism — check any of them against this one
Probiotics for Autoimmune Disease Support
Gut health & immune modulation
10-100 billion CFU daily
B
60%
Magnesium Glycinate
Superior absorption sleep & muscle support
200-600 mg
A
90%
Magnesium Citrate
Balanced absorption & digestive support
300-600 mg
A
35%
Chloride
Electrolyte & digestive support
2300mg
A
95%
Bone Broth Collagen
Gut healing & collagen support
20-40g powder
B
85%
Psyllium Husk
Digestive health & cholesterol support
5-15g
A
95%
Every pair we checked
12 combinations scored by the engine
Glutathione Peroxidase (GPx) + Caffeine
No documented interaction either way
No known interaction
70
Glutathione Peroxidase (GPx) + Creatine Monohydrate
No documented interaction either way
No known interaction
70
Glutathione Peroxidase (GPx) + Calcium Carbonate
No documented interaction either way
No known interaction
70
Glutathione Peroxidase (GPx) + Whey Protein
No documented interaction either way
No known interaction
70
Glutathione Peroxidase (GPx) + Lactase
No documented interaction either way
No known interaction
70
Glutathione Peroxidase (GPx) + Bovine Collagen
No documented interaction either way
No known interaction
70
Glutathione Peroxidase (GPx) + DHA
No documented interaction either way
No known interaction
70
Glutathione Peroxidase (GPx) + Turmeric
No documented interaction either way
No known interaction
70
Glutathione Peroxidase (GPx) + Fish Oil (EPA/DHA)
No documented interaction either way
No known interaction
70
Glutathione Peroxidase (GPx) + Glutathione
Essential cofactor for GPx enzymatic activity
Works better together
82
Glutathione Peroxidase (GPx) + Vitamin D3
Complementary membrane protection against lipid peroxidation
Works better together
82
Glutathione Peroxidase (GPx) + Selenium (Thyroid Support)
Essential mineral cofactor required for GPx synthesis and function
Works better together
82
Dosage
DailySupport via 200-400mcg selenium
Gpx support200-400mcg selenium daily
Deficiency correction200-600mcg selenium daily short-term
Maintenance200mcg selenium daily long-term
MaximumDo not exceed 800mcg selenium daily
When to expect it
First EffectsDepends on selenium status - immediate if adequate selenium present
Peak Benefits4-8 weeks for optimal enzyme activity with selenium repletion
Deficiency DevelopmentGradual decline with selenium deficiency or aging
Toxicity OnsetRare, mainly from excessive selenium intake
How to measure it
MarkerGPx activity, selenium levels, glutathione status, lipid peroxidation markers
OptimalNormal to high GPx activity, adequate selenium levels
Deficient belowLow GPx activity, selenium <70mcg/L
FrequencyBaseline and periodic monitoring, especially with selenium supplementation
Works better with
+
Glutathione
Essential cofactor for GPx enzymatic activity
GSH provides electrons for peroxide reduction · level A
+
Vitamin E
Complementary membrane protection against lipid peroxidation
Vitamin E prevents initiation, GPx reduces existing peroxides · level A
+
Selenium
Essential mineral cofactor required for GPx synthesis and function
Selenocysteine at active site is critical for enzymatic activity · level AWhat not to take with Glutathione Peroxidase (GPx)
!
Excessive Iron
Promotes lipid peroxidation and increases GPx substrate load
Iron catalyzes formation of lipid peroxides · moderate significance
!
Heavy Metals
Mercury and other metals can inhibit GPx activity
Heavy metals bind to sulfur groups and interfere with enzyme function · moderate significanceMedication interactions
Discuss these with a pharmacist before combiningMay interfere with oxidative mechanisms of treatment
What to do: Consult oncologist regarding antioxidant use
Selenium may enhance anticoagulant effects
What to do: Monitor clotting parameters
May enhance protective effects against LDL oxidation
What to do: May improve cardiovascular outcomes
Available forms
Selenium Supplementation for GPx Support: Essential cofactor, Well-absorbed, Direct GPx support, Clinically proven
Food sources
Brazil nuts
Very high selenium content for GPx support · 90
Seafood and fish
High selenium content · 85
Organ meats
High selenium and direct GPx activity · 80
Selenium supplements
Concentrated selenium for GPx support · 95
Too little
- Reduced GPx activity leads to:
- Increased lipid peroxidation and membrane damage
- Elevated cardiovascular disease risk
- Increased cancer susceptibility
- Poor immune function and increased infections
- Muscle weakness and cardiomyopathy (severe deficiency)
- Increased oxidative stress markers
Too much
- Generally safe when supporting through selenium, but monitor for:
- Selenium toxicity with excessive intake (>800mcg daily)
- Hair loss, nail brittleness, garlic breath odor
- Digestive upset and neurological symptoms
- Avoid direct enzyme supplementation due to poor bioavailability
Who benefits most
selenium-deficient
GPx activity directly depends on adequate selenium status
Support through 200-400mcg selenium daily
cardiovascular-risk
GPx protects against LDL oxidation and vascular damage
200-400mcg selenium daily for GPx support
high-oxidative-stress
Enhanced membrane protection against lipid peroxidation
200-400mcg selenium plus glutathione support
aging-adults
Age-related decline in GPx activity and selenium absorption
200mcg selenium daily long-term
immune-support
GPx protects immune cells from oxidative damage
200-300mcg selenium dailyWhere to buy it
Look for Glutathione Peroxidase (GPx) at Support via 200-400mcg selenium per serving. The form that matters here is Selenium Supplementation for GPx Support.
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What else affects it
Beyond other supplements
!
Excessive iron
Promotes lipid peroxidation and increases GPx substrate load
Iron catalyzes formation of lipid peroxides
!
Heavy metals
Mercury and other metals can inhibit GPx activity
Heavy metals bind to sulfur groups and interfere with enzyme functionHow it works
- Reduces lipid hydroperoxides to corresponding alcohols using GSH
- Selenocysteine at active site provides nucleophilic attack on peroxide substrates
- Works with glutathione reductase and NADPH to maintain GSH levels
- GPx4 specifically protects membrane phospholipids from peroxidation
- Prevents formation of toxic lipid peroxidation products
- Maintains cellular redox balance and membrane integrity
Key findings
what the evidence supports- Critical enzyme for membrane protection and cardiovascular health
- Best supported through adequate selenium intake rather than direct supplementation
- Generally safe when supporting through selenium within recommended ranges
- Most effective when combined with glutathione and vitamin E
Sources: NIH Examine.com · data reviewed 2026-08-01
Compiled by Denis, who maintains this database and holds no medical qualification — every figure here is sourced or derived, never asserted. How we calculate it →
Common questions
What are the benefits of Glutathione Peroxidase (GPx)?
Documented effects: Lipid peroxidation protection; Enhanced glutathione utilization; Cardiovascular protection; Enhanced immune function. Prevents oxidative damage to cellular and organellar membranes
How much Glutathione Peroxidase (GPx) should you take per day?
The common daily range is Support via 200-400mcg selenium. By goal — gpx support: 200-400mcg selenium daily; deficiency correction: 200-600mcg selenium daily short-term; maintenance: 200mcg selenium daily long-term; maximum: Do not exceed 800mcg selenium daily.
When is the best time to take Glutathione Peroxidase (GPx)?
With meals. First effects are typically reported within Depends on selenium status - immediate if adequate selenium present.
What are the side effects of Glutathione Peroxidase (GPx)?
At excessive doses: Generally safe when supporting through selenium, but monitor for:, Selenium toxicity with excessive intake (>800mcg daily), Hair loss, nail brittleness, garlic breath odor, Digestive upset and neurological symptoms, Avoid direct enzyme supplementation due to poor bioavailability. Safety rating at normal doses is 8 out of 10.
What should you not take with Glutathione Peroxidase (GPx)?
Separate it from Excessive Iron, Heavy Metals by two to four hours. Promotes lipid peroxidation and increases GPx substrate load
Does Glutathione Peroxidase (GPx) interact with medications?
Documented interactions with chemotherapy, blood-thinners, cholesterol-medications. Discuss these with a pharmacist before combining.
How do you know if you need Glutathione Peroxidase (GPx)?
The marker is GPx activity, selenium levels, glutathione status, lipid peroxidation markers, optimal range Normal to high GPx activity, adequate selenium levels. Common deficiency signs: Reduced GPx activity leads to:, Increased lipid peroxidation and membrane damage, Elevated cardiovascular disease risk, Increased cancer susceptibility.