Processed and red The Western diet, a modern dietary pattern, typically consists of meat, sugar-filled beverages, candies, chocolates, fried foods, prefabricated meals, refined cereals, conventionally produced animal products, high-fat dairy products, and high-fructose items. The goal of this review is to outline how the Western pattern diet affects gut microbiota and mitochondrial fitness, as well as metabolism, inflammation, and antioxidant status. Cancer, mental health, and cardiovascular health; We offer a thorough analysis of how the westernized diet and related nutrients affect immune cell responses as well as the hygienic costs of the Western diet. A consensus critical evaluation utilizing primary sources, including scientific journals, was carried out in order to accomplish this purpose and secondary sources, such as websites, databases, and bibliographic indexes. The project was finished using the Web of Science, Sports Discuss, Embase, Science Direct, ResearchGate, and Scopus. MeSH-compliant terms like "metabolic health," "inflammation," and "Western diet" The terms "metabolism," "oxidative stress," "cancer," "heart disease," "metabolic fitness," and "mental health" were utilized Better knowledge of this dietary pattern, how it affects a person's health and metabolism, and how it affects national sanitary systems will be made possible by this knowledge. Lastly, useful applications based on this knowledge are presented.