The consensus biomedical view of telomeres (typically measured in blood as leukocyte telomere length, LTL) is that their length is reduced with aging, stress, smoking and the metabolic syndrome, and that shorter telomeres impair health. Furthermore, telomere length has been shown to be associated with nutritional status in human and animal studies. Even weight loss is associated with an increase in telomere length. Importantly, new research suggests that a diet that includes soy increases LTL. A pilot study that included 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 program of comprehensive lifestyle changes (diet, activity, stress management, and social support), and the men in the control group underwent active surveillance alone. The experimental diet included one daily serving of tofu plus 58 g of a fortified soy protein powdered beverage. After five years of intervention, relative telomere length and telomerase enzymatic activity per viable cell were measured and compared to baseline values and assessed in relation to the degree of lifestyle changes. 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).
Ornish D, Lin J, Chan JM, et al. Effect of comprehensive lifestyle changes on telomerase activity and telomere length in men with biopsy-proven low-risk prostate cancer: 5-year follow-up of a descriptive pilot study. Lancet Oncol 2013;14:1112-1120.