Nutrients present in various foods plays an important role in maintaining the normal functions of the human body. The major nutrients present in foods include carbohydrates, proteins, lipids, vitamins, and minerals. Besides these, there are some bioactive food components known as “phytonutrients” that play an important role in human health. They have tremendous impact on the health care system and may provide medical health benefits including the prevention and/or treatment of disease and various physiological disorders. Phytonutrients play a positive role by maintaining and modulating immune function to prevent specific diseases. Being natural products, they hold a great promise in clinical therapy as they possess no side effects that are usually associated with chemotherapy or radiotherapy. They are also comparatively cheap and thus significantly reduce health care cost. Phytonutrients are the plant nutrients with specific biological activities that support human health. Some of the important bioactive phytonutrients include polyphenols, terpenoids, resveratrol, flavonoids, isoflavonoids, carotenoids, limonoids, glucosinolates, phytoestrogens, phytosterols, anthocyanins, ω-3 fatty acids, and probiotics. They play specific pharmacological effects in human health such as anti-microbial, anti-oxidants, anti-inflammatory, anti-allergic, anti-spasmodic, anti-cancer, anti-aging, hepatoprotective, hypolipidemic, neuroprotective, hypotensive, diabetes, osteoporosis, CNS stimulant, analgesic, protection from UVB-induced carcinogenesis, immuno-modulator, and carminative. This mini-review attempts to summarize the major important types of phytonutrients and their role in promoting human health and as therapeutic agents along with the current market trend and commercialization.