Quinoa was of great nutritional importance in pre-Columbian Andean civilizations, second only to the Potato, and was followed in importance by Maize. In contemporary times, this crop has become highly appreciated for its nutritional value, as its protein content is very high (12%–18%). Unlike wheat or rice (which are low in lysine), and like oats, Quinoa contains a balanced set of essential amino acids for humans, making it a complete protein source, unusual among plant foods. It is a good source of dietary fibre and phosphorus and is high in magnesium and iron. Quinoa is gluten-free and considered easy to digest.