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For decades, scientists have studied how dietary restriction, without malnutrition, can increase life span and delay the onset of multiple age-related diseases in some mammals.1-3
Purina research showed that maintaining optimal body condition from puppyhood and throughout life can improve both life span and health parameters in dogs.3-5
Purina's research
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Graphic adapted from Kealy et al., 2002
In this landmark study, researchers monitored the health of 48 Labrador Retrievers throughout their lives during which half the dogs were fed 25% less (lean-fed) than their full-fed (control) siblings. The results showed that when dogs were fed to a lean body condition from puppyhood onward, lean-fed dogs lived better, for longer.
- Median life span was extended by 1.8 years or 15%. The mean lifespan for lean-fed dogs was 13 years compared to 11.2 years for control-fed dogs
- The 25% dietary restriction also delayed the onset of signs of chronic disease in these dogs 4
- Diet restriction had no adverse effects on skeletal maturation, structure or metabolism 4
Lean-fed puppies have healthier hips
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By 2 years of age, the frequency of hip dysplasia in the lean-fed dogs was 50% less than in the control group, and was much less severe.
In this graph, the proportion of 12-year old dogs in the lean-fed group with OA was almost the same as that of control-fed dogs that were half that age.
By the end of the study, 83% of dogs fed the control diet had developed radiographic signs of hip OA compared to 50% of the lean-fed group.5
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The prevalence and severity of OA in the shoulder and elbow joints was also lower in the lean-fed dogs. At 8 years of age, the prevalence of OA in two or more joint types was 77% among control-fed dogs, yet only 10% among lean-fed dogs.6
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Lean dogs also experienced other health benefits:
- They showed greater insulin sensitivity, which is better for glucose regulation
- They were better able to maintain immune defense responses over time
- Age–related declines occurred later in life 4
Key things to remember
- A 14-year life span study in Labrador Retrievers showed that when fed to maintain a lean body condition from puppyhood, and throughout life, dogs live better, longer lives.
- The median life span of lean-fed Labrador Retrievers was extended an average of 1.8 years (15%).
- Maintaining optimal body condition throughout life can delay the onset, and reduce the severity, of osteoarthritis in dogs.
- Lean dogs also showed delayed onset of other chronic and age-related diseases.
Explore how nutrition can help pets lead better, longer lives:
Find out more
1. Fontana, L., Partridge, L., & Longo, V. D. (2010). Extending healthy life span--from yeast to humans. Science (New York, N.Y.), 328(5976), 321–326.
2. Kaeberlein, M., Creevy, K. E., & Promislow, D. E. (2016). The dog aging project: translational geroscience in companion animals. Mammalian genome: official journal of the International Mammalian Genome Society, 27(7-8), 279–288.
3. Kealy, R.D., Lawler, D.F., Ballam, J.M., Mantz, S.L., Biery, D.N., Greeley. E.H., & Stowe, H.D. (2002). Effects of diet restriction on life span and age-related changes in dogs. Journal of the American Veterinary Medical Association, 220, 1315-1320.
4. Lawler, D.F., Larson, B.T., Ballam, J.M., Smith, G.K., Biery, D.N., Evans, R.H., & Kealy, R.D. (2008). Diet restriction and ageing in the dog: major observations over two decades. British Journal of Nutrition, 99(4), 793-805.
6. Kealy, R.D., Lawler, D.F., Ballam, J.M., Lust, G., Biery, D.N., Smith, G.K., & Mantz, S.L. (2000). Evaluation of the effect of limited food consumption on radiographic evidence of osteoarthritis in dogs. Journal of the American Veterinary Medical Association, 217(11), 1678-1680.
Additional research related to this 14-year study:
6.1. Huck, J. L., Biery, D. N., Lawler, D.F., Gregor, T. P., Runge, J. J., Evans, R.H., Kealy, R.D., & Smith, G. K. (2009). A longitudinal study of the influence of lifetime food restriction on development of osteoarthritis in the canine elbow. Veterinary Surgery, 38(2), 192- 198.
6.2. Greeley, E. H., Kealy, R.D., Ballam, J. M., Lawler, D. F., & Segre, M. (1996). The influence of age on the canine immune system. Veterinary Immunology and Immunopathology, 55(1-3), 1-10.
6.3. Greeley, E.H., Ballam, J.M., Harrison, J.M., Kealy, R.D., Lawler, D.F., & Segre, M. (2001). The influence of age and gender on the immune system: a longitudinal study in Labrador Retriever dogs. Veterinary Immunology and Immunopathology, 82(1-2), 57-71.
6.4. Greeley, E.H., Spitznagel, E., Lawler, D.F., Kealy, R.D., & Segre, M. (2006). Modulation of canine immunosenescence by life-long caloric restriction. Veterinary Immunology and Immunopathology, 111(3-4), 287-299.
6.5. Kealy, R.D., Olsson, S.E., Monti, K.L., Lawler, D.F., Biery, D.N., Helms, R.W., Lust, G., & Smith, G.K. (1992). Effects of limited food consumption on the incidence of hip dysplasia in growing dogs. Journal of the American Veterinary Medical Association, 201(6), 857-863.
6.6. Kealy, R.D., Lawler, D.F., Ballam, J.M., Lust, G., Smith, G.K., Biery, D.N., & Olsson, S.E. (1997). Five-year longitudinal study on limited food consumption and development of osteoarthritis in coxofemoral joints of dogs. Journal of the American Veterinary Medical Association, 210(2), 222-225.
6.7. Larson, B. T., Lawler, D.F., Spitznagel, E. L., & Kealy, R.D. (2003). Improved glucose tolerance with lifetime diet restriction favorably affects disease and survival in dogs. Journal of Nutrition, 133(9), 2887-2892.
6.8. Lawler, D.F., Evans, R. H., Larson, B.T., Spitznagel, E. L., Ellersieck, M. R., & Kealy, R. D. (2005). Influence of lifetime food restriction on causes, time, and predictors of death in dogs. Journal of the American Veterinary Medical Association, 226(2), 225-231.
6.9. Lawler, D. F., Ballam, J. M., Meadows, R., Larson, B. T., Li, Q., Stowe, H. D., & Kealy, R. D. (2007). Influence of lifetime food restriction on physiological variables in Labrador retriever dogs. Experimental Gerontology, 42(3), 204-214.
6.10. Lawler, D. F., Larson, B. T., Ballam, J. M., Smith, G. K., Biery, D. N., Evans, R. H., & Kealy, R. D. (2007). Diet restriction and ageing in the dog: major observations over two decades. British Journal of Nutrition, 99(4), 793-805.
6.11. Richards, S. E., Wang, Y., Lawler, D., Kochhar, S., Holmes, E., Lindon, J. C., & Nicholson, J. K. (2008). Self-modeling curve resolution recovery of temporal metabolite signal modulation in NMR spectroscopic data sets: application to a life-long caloric restriction study in dogs. Analytic Chemistry Journal, 80(13), 4876-4885.
6.12. Richards, S. E., Wang, Y., Claus, S. P., Lawler, D., Kochhar, S., Holmes, E., & Nicholson, J. K. (2013). Metabolic phenotype modulation by caloric restriction in a lifelong dog study. Journal of Proteome Research, 12(7), 3117-3127.
6.13. Runge, J. J., Biery, D. N., Lawler, D. F., Gregor, T. P., Evans, R. H., Kealy, R. D., Szabo, S. D., & Smith, G. K. (2008). The effects of lifetime food restriction on the development of osteoarthritis in the canine shoulder. Veterinary Surgery, 37(1), 102-107.
6.14. Smith, G. K., Lawler, D. F., Biery, D. N., Powers, M. Y., Shofer, F., Gregor, T. P., & Kealy, R. D. (2012). Chronology of hip dysplasia development in a cohort of 48 Labrador retrievers followed for life. Veterinary Surgery, 41(1), 20-33.
6.15. Stowe, H. D., Lawler, D. F., & Kealy, R. D. (2006). Antioxidant status of pair-fed Labrador retrievers is affected by diet restriction and aging. Journal of Nutrition, 136(7), 1844-1848.
6.16. Szabo, S. D., Biery, D. N., Lawler, D. F., Shofer, F. S., Powers, M. Y., Kealy, R. D., & Smith, G. K. (2007). Evaluation of a circumferential femoral head osteophyte as an early indicator of osteoarthritis characteristic of canine hip dysplasia in dogs. Journal of the American Veterinary Medical Association, 231(6), 889-92.
6.17. Wang, Y., Lawler, D., Larson, B., Ramadan, Z., Kochhar, S., Holmes, E., & Nicholson, J. K. (2007). Metabonomic investigations of aging and caloric restriction in a life-long dog study. Journal of Proteome Research, 6(5), 1846-1854.