Ornithine Alpha-Ketoglutarate (OKG) is a salt formed by combining two molecules of the amino acid ornithine with one molecule of alpha-ketoglutarate. It was developed primarily in French clinical medicine as a nutritional support tool for patients recovering from major surgery, burns, and malnutrition. Today it's also used by athletes and older adults looking to maintain muscle mass and support natural growth hormone release.

OKG works by acting as a precursor to several key compounds in the body, including glutamine, glutamate, proline, and polyamines — all of which play roles in tissue repair and muscle building. It also stimulates the release of anabolic hormones like growth hormone and insulin, which help drive protein synthesis and reduce muscle breakdown. The alpha-ketoglutarate component feeds directly into the energy cycle in cells, supporting recovery during periods of physical stress.

OKG powder is the most common form for supplementation and is often mixed into drinks. Capsules offer convenience for daily use. In clinical settings (hospitals, burn units), OKG has been delivered via enteral (tube) feeding and, historically, intravenously.

• Muscle loss and wasting
• Post-surgery recovery
• Burn and wound healing
• Low growth hormone levels
• Age-related muscle decline (sarcopenia)
• Athletic performance and recovery
• Malnutrition and undernutrition
• Liver health support
• Fatigue and low energy

• Muscle wasting during prolonged hospitalization or immobility
• Nitrogen loss following major surgery or burns

• Meat (beef, chicken, pork) — Best dietary source of L-ornithine, one of the two components of OKG — particularly concentrated in cuts with high protein density.
• Fish (tuna, salmon, mackerel) — Good source of ornithine and also provides alpha-ketoglutarate precursors through their amino acid and metabolite content.
• Eggs — Contain ornithine and a broad spectrum of amino acids that support the same anabolic and tissue-repair pathways OKG targets.
• Dairy (cottage cheese, Greek yogurt) — High-protein dairy provides ornithine and glutamine precursors, supporting muscle protein synthesis and the urea cycle.
• Legumes (soybeans, lentils) — Plant-based sources of ornithine and nitrogen-rich amino acids that support similar metabolic pathways, though at lower concentrations than animal sources.

• Loose stools or diarrhea at high doses (above 10g/day)
• Mild nausea, especially on an empty stomach at higher doses
• Stomach cramping in sensitive individuals
• Possible headache at very high doses
• Theoretical risk of disrupting amino acid balance with very prolonged, high-dose use

• Recommended daily: 5–10g per day for general recovery and athletic use; clinical studies in surgical/burn patients have used 10–30g per day under medical supervision
• Best time of day: For growth hormone stimulation: take 30–60 minutes before bed or before exercise on an empty stomach. For recovery support: can be split across the day with meals.
• With or without food: Best taken without food (or 2+ hours after eating) for maximum growth hormone response; can be taken with food if GI sensitivity is a concern
• Time to effect: Acute GH stimulation within 1–2 hours of a dose; meaningful tissue recovery and anabolic benefits with consistent use over 2–6 weeks
• How long to take it: Safe for continuous use in clinical contexts; for athletic or longevity use, cycling (e.g. 8 weeks on, 2–4 weeks off) is a reasonable precaution though not strictly evidence-mandated