
Does the Artificial Sweetener Sucralose Weaken Immunotherapy?
Cancer Discovery · Jul 30, 2025
Does the Artificial Sweetener Sucralose Weaken Immunotherapy?
Human + mouse data suggest a microbiome → arginine → T-cell axis linking sucralose intake to reduced anti-tumor immunity.
Objective Response Rate
Melanoma: High sucralose consumption 27% vs Low 53% (p=0.037)
NSCLC: High 16% vs Low 60% (p=0.0075)
Pathologic Response
Resectable melanoma: High 12% vs Low 49% (p=0.044)
Progression-Free Survival
Melanoma: 8 mo vs 13 mo
NSCLC: 7 mo vs 18 mo
Response Rate by Sucralose Intake
Melanoma
HighLow
NSCLC
HighLow
Bars ∝ % objective response. High=amber, Low=blue.
Proposed Mechanism
- Sucralose exposure alters gut microbiota.
- ↓ Microbiota-accessible arginine in serum/tumor microenvironment.
- T-cell exhaustion → weakened anti-tumor immunity.
- In mice: Arginine/Citrulline partially restores T-cell activity & PD-1 response.
Microbiome → Arginine → T cells
Other Sweeteners?
- Acesulfame-K: some negative signals, inconsistent.
- Aspartame/Saccharin: no significant effect observed (low intake levels).
- Prior data: sucralose & saccharin may disrupt microbiota; aspartame & stevia show variable effects.



