No one knows why or how collagen, an amorphous protein substance, is formed. However, once deposited between muscle cells, it interferes with normal function and reduces the strength of contraction. This is one reason why systolic blood pressure tends to rise with age. This is separate from the collagen problem and affects the intestinal tract, which is supplied with muscle fibers that contract involuntarily. The result of decreased smooth muscle strength is digestive disturbances, seen as delayed stomach emptying, decreased colonic muscle tone, constipation and depression of the defecation reflex.
Fibrous tissue is non-functioning material made up of tiny scars.
For unknown reasons, it begins to appear in mid-life and causes deterioration of kidney efficiency, loss of hormone production, swelling of the prostate gland and reduction of digestive enzymes. Cataracts and retinal disease may also be related to fibrous degeneration. This contributes to progressively poor nerve functions in old age. At present, none of these changes can be altered by medical treatment. Until scientists can figure out ways to tinker with our aging DNA molecules, we'll just have to keep going, take good care of ourselves, treat our symptoms, joke a lot and wonder what the heck life has in store for us next.