often for long periods of time, and regard that as a
weakness ratherthan as thenew normaland expected
stateofaffairs.We’realwaystrottingoutsomestoryofa
ninety-seven-year-old who runs marathons, as if such
caseswerenotmiraclesofbiologicalluckbutreasonable
expectationsforall.Then,whenourbodiesfailtoliveup
tothisfantasy,wefeelasifwesomehowhavesomething
toapologizefor.Thoseofusinmedicinedon’thelp,for
we often regard the patient on the downhill as
uninterestingunlessheorshehasadiscreteproblemwe
canfix. Ina sense,the advances of modernmedicine
have given us two revolutions: we’ve undergone a
biologicaltransformationofthecourseofourlivesand
alsoaculturaltransformationofhowwethinkaboutthat
course.
THESTORYOFagingisthestoryofourparts.Consider
theteeth.Thehardestsubstanceinthehumanbodyisthe
whiteenameloftheteeth.Withage,itnonethelesswears
away, allowing the softer, darker layers underneath to
showthrough.Meanwhile,thebloodsupplytothepulp
andtherootsoftheteethatrophies,andtheflowofsaliva
diminishes;thegumstendtobecomeinflamedandpull
away from the teeth, exposing the base, making them
unstableandelongatingtheirappearance,especiallythe
lowerones.Expertssaytheycangaugeaperson’sageto
within five years from the examination of a single
tooth—if the person has any teeth left to examine.
Scrupulous dental care can help avert tooth loss, but
growingoldgetsintheway.Arthritis,tremors,andsmall
strokes,forexample,makeitdifficulttobrushandfloss,
and because nerves become less sensitive with age,