Numerous ailments can afflict our bodies, ranging from colds to cancer. There are basically two kinds of diseases: infectious and non-infectious. Infectious diseases are caused by pathogens such as viruses, fungi, bacteria, and parasites. They can enter the body through the air that humans breathe, through the food and drink we consume, or through skin openings such as cuts. For example, a person who has a cold may have gotten it from a doorknob that has a cold virus from another person.
Non-infectious diseases, on the other hand, are not caused by pathogens and cannot be spread person-to-person. These diseases are more likely a result of various factors including the environment, one’s lifestyle choices, and genetics. For example, one who has skin cancer may have gotten it from spending too much time in the sun without protection from the sun’s UV rays, considered an environmental factor. A condition like heart disease may be a result of a sedentary lifestyle and a poor diet, or it may also be caused by a family history of the disease.