A state that occurs when there is an excess of free radicals in the cells of the body is referred to as oxidative stress. The body produces free radicals for normal metabolic processes. Oxidative stress can damage cells, proteins, and DNA, which can lead to aging. It can also contribute to the development of a range of health conditions such as diabetes, cancer, and Alzheimer's. The body naturally produces antioxidants to neutralize or remove these free radicals. Vitamin A, C and E are also important sources of antioxidants. Oxidative stress can be prevented by certain lifestyle and dietary changes such as maintaining healthy body weight, regularly exercising, and eating a balanced and healthful diet. This book discusses the fundamentals as well as modern approaches to oxidative stress. It presents researches and studies performed by experts across the globe. This book will provide comprehensive knowledge to the readers.