People do shrink slightly with age. This is due to a number of factors, loss of muscle tone holding the body upright, bones especially those in the spine being compressed due to carrying weights, gravity etc. My girlfriend in the ambulance service has noticed after working for 17 years she is al least half an inch shorter than when she left school probably due to the lifting of people involved in the job just about every day.

People shrink because as they age, their body loses fat and muscle, which protect their bones from the crushing effects of gravity. Gravity affects the body constantly, and it even shrinks a person over the course of a day. Water in the spinal column is condensed after a day of activity, so people can be slightly shorter at night than they were that morning. This is only temporary, however, and after a good nights rest, the person will be back to their normal height. Another factor that can cause people to shrink is Osteoporosis, which happens when the spongey tissue inside bones breaks down and is not replaced by new tissue. Over the course of someones life, the body begins to lack in essential minerals such as calcium. This, too, can cause the breakdown of bone mass. Thanks to: http://ask.yahoo.com/ask/20021010.html

http://www.seniorjournal.com/NEWS/Aging/5-11-28-SeniorsDoShrink.htm tells us a number of causes and ways to combat them. it is osteoporosis, amongst other things, which is loss of bone density. Exercise, supplements, yoga, can all help.

The principal cause of loss of height is due to osteoporosis, which is a thinning of the bones, particularly those in the spinal column. Small fractures can easily occur just from getting out of a chair. These fractures are painless, and often go unnoticed until there is a noticeable loss of height. It is more prevalent in women as they age, although men can have osteoprosis also. The minute spinal fractures not only reduce height, but cause the condition known as "dowager's hump", where some older ladies develop a stooped-over posture and a severe rounding of the shoulders. There are many ways to combat or prevent this from happening, and the time to start is not to wait until one is older. Good nutrition, plenty of calcium in the diet, weight-bearing exercises, cessation of smoking, and supplements containing calcium, vitamin D and magnesium. Once osteoporosis has taken place, certain medications can stop or even reverse bone loss by building new bone. Some of these are Fosamax or Actonel. There is also a nose spray called Miacalcin. One spray a day in alternate nostrils goes immediately to the bloodstream through the mucous membranes and helps to build bone mass and prevent further loss. "An ounce of prevention is worth a pound of cure", goes the old saying, and it certainly applies in the case of warding off bone loss.

But their noses and ears keep getting bigger.

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The spine has a normal optimal position that best resists gravity and allows for optimal joint and nerve function. It’s only once the spine begins to deviate from this normal position that it begins to “shrink.” Shrinking is common, not normal! Check out http://tinyurl.com/c4vu4d & http://tinyurl.com/b8kj5b