Health Benefits and Future Research of Phytochemicals: A Literature Review.

Phytochemicals are nonnutritive substances found in plant foods that contribute significantly to the flavor and color of foods. These substances are usually classified as polyphenols, terpenes, sulfur-containing compounds, nitrogen-containing compounds, and others. Numerous studies over the last decades have demonstrated these substances play an immeasurable role in physiological regulation, health care, and disease prevention through their actions in antioxidation, anti-inflammation, antiaging, antivirus, anticancer, antithrombosis, lipid profile regulation, cardiovascular protection, neuroprotection, immunity regulation, and improvement of metabolic functions. This article reviews the chemistry and biochemistry of phytochemicals, their classification and chemical structure, occurrence and biosynthesis in plants, and biological activities and implications for human health and various diseases. The discussions are focused on the most recent important advances in these phytochemical researches. In addition, some future research directions of phytochemicals are set forth regarding dose-response, their mechanism and targets, interactions with gut microbiota, and impact on human health and different stages of chronic diseases.