# Eating 30% Less Helped Old Mice Fight Tumors by Waking Up Immune Cells

*Caloric restriction suppresses colorectal tumors and melanoma through CD8 T cells in aged mice.*

- **Evidence Level**: Preliminary
- **Publication Types**: Journal Article
- **Journal**: Cell reports
- **Sample Size**: Aged mice with colorectal cancer or melanoma tumors
- **Authors**: Horino T, Horiguchi H, Torigoe D, Yumoto S, Kadomatsu T, Harada K, Sato M, Moroishi T, Iwatsuki M, Oike Y
- **Published**: 2026-08-17
- **Topics**: Caloric Restriction, Cancer, Immune System
- **DOI**: https://doi.org/10.1016/j.celrep.2026.117844
- **Original Source**: https://pubmed.ncbi.nlm.nih.gov/42606940/

## Summary

In aged mice, cutting calories by 30% slowed the growth of colorectal cancer and melanoma tumors. The reason seems to be immune related. Cutting calories pulled more CD8+ T cells (the immune system's assassins) into the tumors, and when researchers removed those cells, the benefit largely disappeared. This gives a possible explanation for why calorie restriction has been tied to lower cancer risk in animal studies.

## Practical Takeaway

This animal study suggests calorie restriction may support anti-tumor immunity, but human evidence is still missing.

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_Canonical: https://longevity-china.com/en/research/eating-30-less-helped-old-mice-fight-tumors-by-waking-up-immune-cells · Part of Longevity Cities · Updated 2026-08-17_