Antioxidants are substances that prevent oxidation of other compounds or neutralize free radicals. Spices and herbs are rich sources of antioxidants. Spices are rich in antioxidants, and scientific studies suggest that they are also potent inhibitors of tissue damage and inflammation caused by high levels of blood sugar and circulating lipids. They have been used in food and beverages to enhance flavor, aroma and color. Due to their excellent antioxidant activity, spices and herbs have also been used to treat some diseases. In this review article, the chemical composition and antioxidant activity of spices and culinary herbs are presented. Lipid oxidation has been identified as the major deterioration process of vegetable oils. Undesirable effects are even more profound when food processing involves high temperatures in the presence of oxygen. Natural ground herbs (black pepper, ginger, turmeric, rosemary, and oregano) were assessed for their antioxidant capacity, phenolic content and ability to improve the oxidative stability of vegetable oils. In the current set-up, the anti-proliferative, anti-hypercholesterolemic, anti-diabetic, anti-inflammatory effects of spices have overriding importance is discussed. Spices have very low-calorie content and are relatively inexpensive; they are reliable sources of antioxidants and other potential bioactive compounds in the diet.