5-Year Follow-Up of a Descriptive Pilot Study
Lancet Oncol. 2013 Oct 01;14(11)1112-1120, D Ornish, J Lin, JM Chan, E Epel, C Kemp, G Weidner, R Marlin, SJ Frenda, MJ Magbanua, J Daubenmier, I Estay, NK Hills, N Chainani-Wu, PR Carroll, EH Blackburn
TAKE-HOME MESSAGE
- Can lifestyle changes affect telomere length?
- Increased telomere length is associated with slower physiologic aging and lower risk of developing a variety of diseases.
- In this small pilot study, the long-term effects of a healthy diet and lifestyle interventions were associated with increased telomere length. A larger study is warranted.
Commentary by David Rakel, MD, FAAFP
The lesson of this study reaches beyond prostate cancer to how lifestyle can affect the longevity of our cells. Each of our chromosomes has a telomere on the end, similar to the compressed end of a shoe lace, which helps prevent the loss of nucleotides with each cell division. The longer the better, as telomeres help stabilize cell function and protect the chromosomes. The enzyme telomerase helps replace the end of the shoe lace, and we want plenty of telomerase to help keep telomeres long. In cancer, shortened telomeres are associated with more cancer growth as the friable ends of the chromosome are prone to mutations, which means that there is a greater risk of having a more lethal case of prostate cancer. Short telomeres are also associated with aging, stroke, vascular dementia, diabetes, osteoporosis, and obesity.
Dean Ornish and colleagues lengthened their original 3-month GEMINAL study to 5 years to see what effect lifestyle would have over a longer period of time. The lifestyle changes consisted of:
- Whole food; low-fat (10% of calories), plant-based diet
- Moderate aerobic exercise (walking 30 minutes/day, 6 days/week)
- Stress management (yoga, stretching, breathing, meditation, imagery for 60 minutes/day)
- Social support (60-minute support group sessions once per week)
- Telomeres were measured in leukocytes at baseline and after 5 years. The lifestyle group was compared with a control group of men with-low grade prostate cancer who did not make lifestyle changes. High adherence scores to the lifestyle changes correlated with longer telomeres; telomeres shortened in the control group.
This study was small but gives us a glimpse into the importance of pragmatic outcome trials that show how comprehensive healthy behaviors can work synergistically toward long-term health. This study and countless others support the trend that health is more about what we do than what we take.
ABSTRACT
Background: Telomere shortness in human beings is a prognostic marker of ageing, disease, and premature morbidity. We previously found an association between 3 months of comprehensive lifestyle changes and increased telomerase activity in human immune-system cells. We followed up participants to investigate long-term effects.
Methods: This follow-up study compared ten men and 25 external controls who had biopsy-proven low-risk prostate cancer and had chosen to undergo active surveillance. Eligible participants were enrolled between 2003 and 2007 from previous studies and selected according to the same criteria. Men in the intervention group followed a programme of comprehensive lifestyle changes (diet, activity, stress management, and social support), and the men in the control group underwent active surveillance alone. We took blood samples at 5 years and compared relative telomere length and telomerase enzymatic activity per viable cell with those at baseline, and assessed their relation to the degree of lifestyle changes.
Findings: Relative telomere length increased from baseline by a median of 0·06 telomere to single-copy gene ratio (T/S)units (IQR—0·05 to 0·11) in the lifestyle intervention group, but decreased in the control group (−0·03 T/S units, −0·05 to 0·03, difference p=0·03). When data from the two groups were combined, adherence to lifestyle changes was significantly associated with relative telomere length after adjustment for age and the length of follow-up (for each percentage point increase in lifestyle adherence score, T/S units increased by 0·07, 95% CI 0·02—0·12, p=0·005). At 5 years, telomerase activity had decreased from baseline by 0·25 (—2·25 to 2·23) units in the lifestyle intervention group, and by 1·08 (—3·25 to 1·86) units in the control group (p=0·64), and was not associated with adherence to lifestyle changes (relative risk 0·93, 95% CI 0·72—1·20, p=0·57).
Interpretation: Our comprehensive lifestyle intervention was associated with increases in relative telomere length after 5 years of follow-up, compared with controls, in this small pilot study. Larger randomised controlled trials are warranted to confirm this finding.
Journal Abstract: http://www.thelancet.com/journals/lanonc/article/PIIS1470-2045%2813%2970366-8/abstract