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Limited evidenceLongevity & antioxidants

SOD (Superoxide Dismutase)

Plain oral SOD is an enzyme destroyed by stomach acid and digestion, so it does nothing systemically. Gliadin-coated melon SOD extracts survive better and have a handful of small trials showing modest antioxidant-enzyme and fatigue effects — worth knowing, but far short of proof.

What the science says

  • Unprotected oral SOD raises body antioxidant capacity Limited evidence

    SOD is a 32 kDa metalloprotein. Swallowed without protection, it is denatured by gastric acid and cleaved by pancreatic proteases into amino acids, like any other dietary protein. Products listing raw SOD activity units on the label are selling an enzyme that will not reach the bloodstream intact — the units measure in-vitro activity, not anything delivered to your cells.

  • Gliadin-combined melon SOD reduces fatigue Limited evidence

    In a randomized placebo-controlled trial of 61 women aged 50–65, a wheat-gliadin-bonded melon SOD extract (about 500 mg/day for 8 weeks) improved several self-perceived fatigue subscales versus placebo. Sample was small, outcomes were subjective, and results come largely from groups linked to the ingredient supplier.

  • Induces endogenous antioxidant enzymes Limited evidence

    The proposed mechanism is not delivery of the enzyme but signaling from the gut that upregulates the body's own SOD, catalase and glutathione peroxidase. Small human trials of melon SOD concentrate (roughly 10–140 mg/day, 2–4 weeks) have reported increases in these enzymes and reductions in oxidative-damage markers, but sample sizes are typically under 50 and no independent replication of clinical benefit exists.

Dosage & safety

Studied doseStudied gliadin-combined melon SOD products supply roughly 140–500 mg/day of the combined extract, standardized to about 10–140 IU SOD activity, taken for 4–12 weeks. Note the SOD activity number is small compared with the raw-SOD products advertising thousands of units — a reminder that units on the label are not a measure of what gets absorbed.
SafetyWell tolerated in the short trials that exist; the main issue is composition, not toxicity. Gliadin-bonded forms contain wheat protein and are unsuitable for coeliac disease or wheat allergy — check for a gluten-free carrier if that applies. Melon-derived extracts should be avoided in melon allergy. Bovine-derived SOD raises the usual animal-tissue sourcing questions. No known drug interactions, not banned in sport. If you want higher antioxidant enzyme activity, the evidence for exercise and a plant-rich diet is far stronger than for any SOD capsule.

Scientific references

Where to buy

Source Naturals, SOD Power™, 250 mg, 60 Tablets

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