**1. Introduction**

Super food is a nonmedical, marketing term that refers to natural foods supposed to be useful for health because they are rich in a particular antioxidant or any other nutrient [1]. They are edibles that deliver the maximum amount of nutrients with minimum calories [2]. They help pets fight disease, maintain healthy skin and shiny coat, improve healthy digestion,

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© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, © 2017 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

maintain joints and strong bones, fight tartar and bad breath, whiten teeth, detoxify the body system, boost immune system, promote longevity, boost energy, and maintain good health in general [3]. Unlike super foods, functional foods are natural or processed foods [1]. They contain considerable levels of biologically active components that impart health benefits beyond the basic essential nutrients [4, 5]. They also provide clinically proven and documented health benefits for the prevention, management, or treatment of chronic diseases [6]. The philosophy of food as medicine was supported by Hippocrates in approximately 400 B.C. [7]. This thinking is the foundation of functional foods used to clarify the idea that food can be a powerful deterrent and cure of many diseases and ailments. Hippocrates believed that the things eaten can help the body fend off disease and food should be the first line of disease defense, used as a disease preventative mechanism. Previous studies have provided great examples of how specific ingredients in some pets' foods can act as medicines [8]. In the past, many of the perceptions about healthy eating have focused on avoiding certain components in foods, such as fat and sugar. Nutritional research has shifted from the prevention of nutritional deficiencies, such as vitamin C and scurvy or niacin and pellagra, to the prevention of chronic diseases [4]. Most pets do not receive an adequate amount of raw, essential nutrients in their diet especially in highly processed commercial pet food. Most of the natural pet foods go through a great deal of cooking, rendering, and sterilizing thereby reducing the essential nutrients [3].

Examples of super food and functional foods are oats, garlic, green tea, red grape juice, red wine, tomatoes, soy products, flaxseed, broccoli, cocoa, blueberries, carrots, sweet potatoes, pumpkin, onions, kale, cherries, and apples [9]. Oats contain beta-glucan, a soluble fiber, which aids to reduce the risk of cardiovascular disease by lowering blood cholesterol. Garlic is rich in allicin and lowers cholesterol levels and blood pressure [10]. It also stimulates immune function and slows the growth of cancer cells. Green tea contains polyphenols and may help prevent cancer [9]. Red grape juice and red wine contain resveratrol, which aids in prevention of heart disease and cancer [11]. Tomatoes contain lycopene, a carotenoid that helps to reduce risk for cancer of the colon, prostate, bladder, and pancreas [9, 12]. Soy products (tofu, tempeh, soy milk, miso, etc.) contain genistein and isoflavones [13]. These compounds contain blood vessel formation that supplies cancer cells and hinder the body's synthesis of estrogen, thereby reducing the risk for breast, ovarian, and prostate cancer [14]. Flaxseed that contains lignans, powerful antioxidants, stops cells from becoming cancerous. It also contains alpha-linolenic acid, a type of plant omega-3 fatty acids that may lessen the risk of heart disease [9]. Broccoli has indoles that protect cells against carcinogens and aids the liver inactivate estrogen-like compounds that may sustain formation of breast cancer [2]. Cocoa has similarly been claimed to cut the risk of heart disease by lowering blood pressure and increasing the elasticity of blood vessels. This is thought to be due to cocoa's high content of compounds called flavonoids [15, 16]. Blueberries, carrots, sweet potatoes, and pumpkin provide healthy vitamins including A, B, and C that are good for a healthy coat and immune system [2]. Onions, kale, cherries, and apples contain quercetin that also helps to fight cancer and heart disease [14, 17]. Other fruits that have super food status include açaí berries and pomegranates. The fruit pulp of açaí berries has been shown to have potent antioxidant properties [18, 19]. Researchers have recognized these components and are trying to determine exactly what benefits they may present [20].
