Cancer is a disease characterized by the uncontrolled growth and spread of abnormal cells. Around the world, over 10 million cancer cases occur annually. Over one million people in the United States get cancer each year. Anyone can get cancer at any age; however, about 80 percent of all cancers occur in people over the age of fifty-five. Cancer can affect any site in the body. About one hundred human cancers are recognized. There is a marked variation among countries in incidence of different cancers. Most of the variation in cancer risk among populations, and among individuals, is due to environmental factors, such as cigarette smoking and certain dietary patterns, which can affect one’s risk of developing cancer. All cancers caused by cigarette smoking and heavy use of alcohol could be prevented completely. Approximately 30 percent of all cancers worldwide are due to tobacco use. Many of the skin cancers could be prevented by protection from sunlight. Certain cancers that are related to infectious exposures could be prevented through behavioural changes, vaccines, or antibiotics. The relation between dietary components (Functional Foods) and a disease are regulated by the United States Food and Drug Administration (FDA) under the authority of two laws; The Federal Food, Drug, and Cosmetic Act (FD&C) of 1938 provides for the regulation of all foods and food additives. Eating habits in high and low socioeconomic (SES) groups is considered as one of the most powerful predictors of health status and mortality worldwide. High-risk health behaviours are more common in persons of low SES (LSES). The excess mortality and morbidity associated with LSES have commonly been attributed to high-risk health behaviours including diet, smoking, lack of physical activity, and obesity .Further, the increase incidence of cancer risk in different population was associated mainly with consumption of preserved fish, cold cuts , oleaginous fruits, alcohol, pasta , rice, and eggs. Diets rich in vegetables, fruits and with low amounts of salty and starchy foods are recommendable for the prevention of gastric cancer. Right fat, fiber intake , Raw fruits and vegetables, Switch from red meat to seafood, Switch from an animal-based diet to a plantbased diet, intake Foods containing calcium, Diet high in antioxidants, Vitamin D, Selenium, garlic and green tea supports the immune system and fit into cancer disease-risk reduction.