Reduce your chances of becoming infected with flu or other diseases that are caused by bacteria in the air. You can improve the lives of family members or employees who suffer from various allergies caused by breathing. Prevention of early chemical exposure is critical. Many scholars believe that disease is a continuous process in the body that may take years to evolve from the earliest stage. Therefore a fetus or newborn exposed to a toxin that causes cancer early will have a greater chance of developing a disease later in life - simply because it will have more time to evolve.