Information on food composition including types and contents of nutrients and anti-nutrients is important for food and nutrition research. There is satisfactory information on established nutritive elements for various food groups. However, literature on anti-nutrient component generally scattered and scanty on few major food groups and commonly consumed plant parts. A better understanding of both the positive and negative qualities of vegetable component would help develop better evidence-based promotion and appropriate dietary strategies. This paper reviews seven types of anti-nutrient elements in vegetables: oxalates, phytates, nitrates, tannins, glucosinolates, saponins and alkaloids and their effects, mechanisms, content and processing methods. A total of 360 research papers were systematically identified and 123 were selected with acceptable anti-nutrient data. Vegetable families and plant parts with highest content of each anti-nutrient were identified, with the Leguiminosae family having highest content of phytate, tannins and saponins, and leafy vegetables having high oxalate. The simplest food processing methods to reduce anti-nutrients in vegetables are boiling and removal of certain plant parts. While consumption of vegetables with anti-nutrients do not normally cause adverse effects in the general population, future research to determine nutrient bioavailability based on diets will help increase awareness and improve recommendations on plant food intake.