Humans are made up of trillions of cells and each can trace its heritage back billions of years. These cells originally survived on their own and still have much of the complicated machinery for life. So cells are incredibly complicated and very capable meaning the number of factors involved in maintaining their balance (homeostasis) is more than for basic forms of life.
Cells maintain a separate internal environment to their surroundings and tightly control what goes in or out. They also work with the trillions of other cells that make up a human which requires complicated mechanisms to orchestrate well.
So cells are involved intricately in managing every aspect of a human therefore the more you know about providing for your cells the better your experience of life will be. Even a little knowledge can go a long way.
This topic is about life sciences and how cells work both individually and as groups and organisms. Take your time and learn as you go.