GDF-11 (Growth Differentiation Factor 11) vs Klotho
A neutral, side-by-side comparison of two anti-aging & longevity peptides — their mechanisms, dosing ranges, administration routes, side effects, and research evidence. For research and educational purposes only.
GDF-11 (Growth Differentiation Factor 11)
TGF-β superfamily member proposed as a 'young blood factor' — circulating GDF-11 declines with age, and young plasma transfusion in parabiosis experiments reversed aging phenotypes in mice. A high-profile but contested research area: some studies show rejuvenating effects in heart, muscle, and brain; others using purified recombinant GDF-11 show cardiac hypertrophy and muscle wasting at pharmacologic doses.
Full profileKlotho
Anti-aging protein discovered in 1997 whose deficiency causes a syndrome resembling accelerated aging across multiple organ systems. Circulating soluble klotho declines ~40% from age 40–80. Research into klotho-derived peptides and recombinant protein explores neuroprotection, cardiac protection, renal anti-fibrosis, and metabolic anti-aging benefits. The KL-VS polymorphism provides a natural human model of elevated klotho activity.
Full profile| GDF-11 (Growth Differentiation Factor 11) | Klotho | |
|---|---|---|
| Category | Anti-Aging & Longevity | Anti-Aging & Longevity |
| Also known as | GDF11, Bone Morphogenetic Protein 11, BMP-11, young blood factor | α-Klotho, soluble Klotho, KL-VS, klotho protein, KL1 domain |
| Evidence | Research-stage | Research-stage |
| Dosing range | 0.1mg/kg–1mg/kg mg/kg, every 3–7 days (SC); research protocols vary widely | 1mcg/kg–10mcg/kg mcg/kg, every 3–7 days IV or SC (research) |
| Administration | Subcutaneous injection, Intravenous (research) | Intravenous (research), Subcutaneous injection |
| Key side effects | Cardiac hypertrophy (at pharmacologic doses — the key safety concern), Muscle wasting and weight loss, Reproductive effects (GDF-11 inhibits spermatogenesis and folliculogenesis), Cachexia-like syndrome at high doses | Hypophosphatemia (klotho inhibits FGF23 signaling → phosphate wasting), Hypocalcemia (secondary to phosphate effects), Altered vitamin D metabolism, Potential for altered mineral homeostasis with chronic administration |
| Cited sources | 2 references | 2 references |
Key differences
- Administration: GDF-11 (Growth Differentiation Factor 11) — Subcutaneous injection, Intravenous (research); Klotho — Intravenous (research), Subcutaneous injection.
- Dosing units differ: GDF-11 (Growth Differentiation Factor 11) is dosed in mg/kg, Klotho in mcg/kg — they operate at different scales.
- Frequency: GDF-11 (Growth Differentiation Factor 11) is typically every 3–7 days (SC); research protocols vary widely; Klotho is every 3–7 days IV or SC (research).
How each works
GDF-11 (Growth Differentiation Factor 11)
The 2013–2014 parabiosis studies from Amy Wagers' lab at Harvard proposed GDF-11 as the primary rejuvenating factor in young blood. However, subsequent work by Lee and others showed that purified recombinant GDF-11 at pharmacologic doses caused cardiac hypertrophy, muscle atrophy, and weight loss — opposite of the proposed rejuvenating effects. The field now views GDF-11 as highly dose-sensitive with a narrow therapeutic window, if one exists at all.
Klotho
α-Klotho functions as both a transmembrane co-receptor for FGF23 (regulating phosphate and vitamin D) and as a shed soluble circulating factor with FGF23-independent longevity effects. Soluble klotho activates longevity-associated pathways: Nrf2/antioxidant defense, FOXO transcription factors, and Wnt/TGF-β inhibition for anti-fibrotic effects. The klotho-deficient mouse ages rapidly and dies young; klotho-overexpressing mice live 20–30% longer.
This comparison aggregates public research and structured profile data for informational purposes only. It is not medical advice and does not recommend either compound for human use. Consult a qualified healthcare provider before considering any peptide.