Watercress’s benefits are nothing new. For decades, it only made appearances as a plate garnish, but it used to be a staple in the diet of Roman soldiers. But watercress is no longer ornamental, largely because of its off-the-charts ANDI score.
ANDI score rates food based on the number of minerals, vitamins and phytonutrients in relation to total calories. Watercress has the highest score among all foods; it offers the highest amount of nutrients for the lowest amount of calories. Watercress is considered a superfood and it is inexpensive.
Weight for weight, watercress contains more vitamin C than an orange, more calcium than milk, more iron than spinach and more folate than bananas.
Note: Watercress is considered 'cooling' in TCM, so do not consume too much if you are old or always feeling cold. As it is very bitter, this is another reason for not using too much of it in smoothie.