African nightshades (ANs) are among the most popular African traditional leafy vegetables in several countries in sub-Saharan Africa. When accessible and available, they can contribute to food security, improving nutrition and economic opportunities in African people's livelihood. Recent years have witnessed the expansion of attention and research into the nutrition of ANs. In particular, knowledge of the phytochemistry of ANs has been greatly advanced. This work summarizes ANs' nutrient content and reviews the major phytochemicals of polyphenols, glycoalkaloids, and saponins in the plants' leaves and berries to shed light on the associated micronutrients and possible toxicity. This review also reveals the remaining knowledge gaps yet to be filled to further facilitate the full utilization of ANs in sub-Saharan Africa.