Back to Health Risk Assessment â Body Composition Because water is contained primarily in fat-free tissues - the muscles - the percentage of total body water can vary widely between individuals. Those with a high percent body fat can be as low as 40% total body water, while very lean individuals and athletes can attain 70%. Water is the essential component of all vital fluids and the medium of transport in every biological exchange.
Definition of ophthalmology. : a branch of medical science dealing with the structure, functions, and diseases of the eye.
An ophthalmologist is a medical doctor (M.D.) specializing in eye care. After the completion of four years of undergraduate study, an ophthalmologist must complete four years of medical school and spend a minimum of four years of residency (hospital-based training). An optometrist has a degree of doctor of optometry.