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Limited evidenceLongevity & antioxidants

Oxaloacetate

A Krebs-cycle intermediate sold for fatigue and ageing. One non-randomized trial in ME/CFS and long-COVID fatigue reported improvement, which is far too weak a base for the longevity claims.

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What the science says

  • Fatigue in ME/CFS and long COVID Limited evidence

    A non-randomized controlled clinical trial gave oxaloacetate to patients with ME/CFS and long-COVID fatigue and reported reductions in mental and physical fatigue scores versus historical controls. Without randomization or blinding, placebo and expectation effects cannot be separated from any real effect.

  • Longevity and metabolic effects Limited evidence

    A systematic review of dietary supplements for fatigue in ME/CFS included oxaloacetate among candidates with preliminary signals only and called for randomized trials. Claims about lifespan extension come from C. elegans and rodent work, not humans.

Dosage & safety

Studied doseThe fatigue study used 500–2,000 mg/day of anhydrous enol-oxaloacetate in divided doses. No dose has been validated in a randomized trial.
SafetyReported as generally well tolerated at these doses in short studies, with occasional gastrointestinal upset and headache. Long-term safety is unknown, and it may affect blood glucose. Not studied in pregnancy, breastfeeding or children; discuss with a doctor if you take diabetes medication.

How to take it

TimingSplit into two or three doses across the first half of the day, as in the fatigue study.
With food?With or without food; no absorption difference has been established.
Worth knowingOxaloacetate degrades readily with heat and moisture — keep the bottle cool, closed and dry, and do not buy more than you will use.

Interactions

With medications

  • diabetes medication

    Oxaloacetate feeds directly into glucose metabolism and may affect blood sugar. monitor blood glucose and talk to your doctor before combining

Well-established interactions only — this is not a complete list. Always tell your doctor and pharmacist what you take.

Frequently asked questions

Does oxaloacetate help with chronic fatigue or long COVID?

The evidence is limited: one non-randomized trial in ME/CFS and long-COVID fatigue reported lower fatigue scores with oxaloacetate versus historical controls. Without randomization or blinding, placebo effects cannot be separated from any real effect.

Does oxaloacetate extend lifespan?

The lifespan claims for oxaloacetate come from C. elegans worms and rodents, not humans. No human trial supports oxaloacetate for longevity.

How much oxaloacetate should I take per day?

The fatigue study used 500–2,000 mg/day of anhydrous enol-oxaloacetate split into two or three doses across the first half of the day. No dose has been validated in a randomized trial.

Is oxaloacetate safe with diabetes medication?

Oxaloacetate feeds directly into glucose metabolism and may affect blood sugar, so monitor your glucose and talk to your doctor before combining it with diabetes medication. Occasional stomach upset and headache are the other reported side effects, and long-term safety is unknown.

Scientific references

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