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Updated: Aug 13, 2026
06:13
Solid Plate-based Dietary Restriction in Caenorhabditis elegans
Published on: May 28, 2011
Housing density does not influence the longevity effect of calorie restriction
Yuji Ikeno1, Gene B Hubbard, Shuko Lee
1Geriatric Research, Education and Clinical Center, South Texas Veterans Health Care Systems, San Antonio, TX, USA.
Summary
Calorie restriction (CR) effectively extends lifespan and delays disease in mice, regardless of housing density. While CR
Area of Science:
- Gerontology
- Animal Science
- Nutritional Science
Background:
- Calorie restriction (CR) is known to extend lifespan and delay age-related diseases.
- The impact of environmental factors, such as housing density, on CR's efficacy is not fully understood.
- Understanding these interactions is crucial for optimizing healthspan interventions.
Purpose of the Study:
- To investigate how housing density affects the longevity-promoting and disease-delaying effects of calorie restriction.
- To determine if the benefits of CR are consistent across different housing conditions.
- To explore potential differential effects of CR on specific diseases based on housing.
Main Methods:
- Mice were housed individually or in groups of four.
- Animals were assigned to either ad libitum (AL) feeding or calorie restriction (CR) starting at 2 months of age.
- CR involved a 40% reduction in food intake compared to multiply housed AL mice.
Main Results:
- Calorie restriction increased median longevity by 19%, with no significant effect of housing density on this lifespan extension.
- CR reduced neoplastic lesions in both singly and multiply housed mice.
- Lymphoma, a common neoplasm, showed a greater reduction in singly housed CR mice compared to multiply housed CR mice.
Conclusions:
- Calorie restriction extends lifespan effectively in both singly and multiply housed mice.
- Housing density does not diminish the overall life-extending benefits of CR.
- Housing density may differentially influence the cancer-protective effects of CR, particularly for lymphoma.
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