1. Intoduction

Balanced diet is important for maintaining good health. If balanced diet is not taken, people suffer from malnutrition. This is one of the causes for ill-health. But in human beings health is also upset or spoiled due to lack of clean water, clean air, and hygienic food. Besides these, poverty, illiteracy and over population are also the major factors that cause ill-health and diseases. A disease is an abnormal condition that affects the body of an organism. It may be caused by factors originally from an external source, such as infectious diseases or it may be caused by internal dysfunctions, such as autoimmune diseases. Some diseases also caused by micro- organisms. In this unit you learn some aspects concerning good health, onset of diseases and prevention and cure of the diseases.

The human microbiome plays a vital role in maintaining homeostasis of various organ systems and protecting against infectious agents. It can be subcategorized into local or regional microbiomes throughout the body, such as the gut, oral, skin, lung, and vaginal microbiomes. These manicured microecosystems are highly organized and complex, with each person having their own distinct makeup and distribution of various microorganisms. Though, individual microbiomes are unique, there is still capacity to understand key role players in the community and their potential for adaptation to improve human health in general.

Attribution:  ""3.1: Human Health and Disease" by Dylan Parks, LibreTexts platform. is licensed under CC BY 4.0