Eating well, exercising regularly and reducing stress can extend life, even if you’ve been dealt a poor genetic hand, according to a small pilot study.
The study, which was done at the University of California, San Francisco, showed that diet, exercise and lower stress can actually lengthen telomeres, a region of a DNA strand at the end of a chromosome that protects the end of the chromosome from deterioration.
In recent years, scientists have determined that shorter telomeres are associated with a broad range of aging-related diseases, including many forms of cancer, stroke, vascular disease, cardiovascular disease, obesity, osteoporosis and diabetes.
“Our genes, and our telomeres, are not necessarily our fate,” said lead author Dean Ornish, MD, UCSF clinical professor of medicine, and founder and president of the Preventive Medicine Research Institute.
“So often people think ‘Oh, I have bad genes, there’s nothing I can do about it,’” Ornish said. “But these findings indicate that telomeres may lengthen to the degree that people change how they live. Research indicates that longer telomeres are associated with fewer illnesses and longer life.”
For the study, 35 men with early-stage prostate cancer were followed. Ten of the men adopted a plant-based diet, started a regimen of moderate exercise, yoga and meditation as well as taking part in a weekly group support session. The others were not asked to make any lifestyle changes.
According to the results, the men that made healthy lifestyle changes experienced “significant” increase in telomere length - up to 10 percent. The men who were most dramatic in lifestyle changes saw greater growth of telomeres.
By contrast, the men in the control group who were not asked to alter their lifestyle had measurably shorter telomeres – nearly 3 percent shorter – when the five-year study ended. Telomere length usually decreases over time.
The researchers say the findings may not be limited to men with prostate cancer, and are likely to be relevant to the general population.
“We looked at telomeres in the participants’ blood, not their prostate tissue,” said Ornish.
The new study is a follow up to a similar, three-month pilot investigation in 2008 in which the same participants were asked to follow the same lifestyle program. After three months, the men in the initial study exhibited significantly increased telomerase activity. Telomerase is an enzyme that repairs and lengthens telomeres.
The study was published online on Sept. 16 in The Lancet Oncology.
Here's a short video about the study:
Telomere
From Wikipedia, the free encyclopedia
http://en.wikipedia.org/wiki/Telomere
A telomere is a region of repetitive nucleotide sequences at each end of a chromatid, which protects the end of the chromosome from deterioration or from fusion with neighboring chromosomes. Its name is derived from the Greek nouns telos (τ?λος) 'end' and merοs (μ?ρος, root: μερ-) 'part.' Telomere regions deter the degradation of genes near the ends of chromosomes by allowing chromosome ends to shorten, which necessarily occurs during chromosome replication. Without telomeres, the genomes would progressively lose information and be truncated after cell division because the synthesis of Okazaki fragments requires RNA primers attaching ahead on the lagging strand. Over time, due to each cell division, the telomere ends become shorter.
During cell division, enzymes that duplicate DNA cannot continue their duplication all the way to the end of chromosomes. If cells divided without telomeres, they would lose the ends of their chromosomes, and the necessary information they contain. The telomeres are disposable buffers blocking the ends of the chromosomes, are consumed during cell division, and are replenished by an enzyme, telomerase reverse transcriptase.
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http://zh.wikipedia.org/wiki/%E7%AB%AF%E7%B2%92
