Considering Longevity
Genetics and Longevity
What contributed to Jeanne Calment's longevity? Is her family history related to her longevity? Jeanne Calment belonged to a family with long-lived members, providing indirect evidence of the importance of genetics. Several generations of Jeanne's relatives lived near Arles in Southern France, allowing gerontologists to trace 116 ancestors back to 1723; of this large group of relatives, the life span of 55 ancestors could be verified.[2] These studies revealed a striking number of long-lived relatives. When compared with a control population of nonrelatives born during the same period, 13 of 55 of Jeanne's family members lived to more than 80 years, compared with only 1 of 55 in the control group (P < .001).
Even though inherited genetic factors certainly contributed to Jeanne's extreme longevity, finding a single longevity gene or combination of longevity genes has proven elusive. A meta-analysis of several studies found no genes that extended life but did find 1 gene, ApoE E4, associated with a decreased life span.[3] The search for longevity and healthy aging continues to be a fertile research field, especially now that sequencing an individual's entire genome has become affordable.
Smoking and Longevity
There is solid evidence that smoking is associated with an increased risk for benign and malignant diseases that shorten one's life span by several years.[4] Jeanne Calment smoked in moderate amounts -- a few cigarettes a day -- from age 21 years (when she was married) until the age of 117 years (when she gave up smoking), for a total of 96 years! Even though her daily exposure was minimal, she was fortunate to have avoided a life-shortening tobacco-related illness because, over such a long time, her cumulative number of pack-years of exposure would have been substantial.
Diet and Longevity
In addition to genetic factors, does diet have anything to do with longevity? Obesity is associated with heart disease and cancer, but few centenarians are obese -- Jeanne Calment weighed less than 100 lb at the time of her death. Did she consume a special diet that prolonged her life? Throughout her life, Jeanne Calment had a good appetite, eating a varied diet including fried and spicy foods. When asked about her digestion, she said: "I have the stomach of an ostrich."
However, similar to the Aztec ruler Montezuma, Calment loved chocolate, reputedly consuming as much as 2 lb of chocolate per week. Does chocolate promote health and do "chocoholics" possibly live longer than other people? Several investigators have looked for a possible association between chocolate consumption and health. Hooper and colleagues[5] conducted a meta-analysis of the association between chocolate and cardiovascular disease and found that chocolate consumption resulted in lower blood pressure and improved insulin resistance. Djoussé and colleagues[6] found that chocolate consumption was inversely associated with calcific coronary artery disease. Desideri and colleagues[7] observed that chocolate improved some aspects of cognitive function. The available evidence supports a limited role for chocolate consumption as a possible explanation for Jeanne Calment's remarkable longevity.
What about reduced-calorie diets? Animal data support an association between caloric restriction and longevity, but does it hold for humans? The evidence is inconclusive; rather than caloric restriction, the putative improvement in life span may be caused by the higher nutritive quality of a reduced caloric intake.[8,9,10] A starvation diet may not increase an individual's life expectancy, but it will certainly make one's life seem longer.
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Cite this: The Case of the Woman Who Shattered a World Record - Medscape - Mar 27, 2014.
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