Watercress, spinach and chicory are the most nutritious vegetables you can eat

We all know that fruit and vegetables are good for us - but just how good?
A new league table, showing the nutrient density of different fruits and vegetables, has been drawn up by diet experts - and watercress has come out on top. The researchers, from the William Paterson University of New Jersey, aimed to define ‘powerhouse fruit and vegetables’.
They tested 47 different types of fruit and vegetables for their levels of 17 nutrients which are generally considered to be of high importance to our health. The nutrient density score was based on the percentage of a person’s daily needs for each nutrient the food provides.
The foods were scored by their content of potassium, fibre, protein, calcium, iron, thiamin, riboflavin, niacin, folate, zinc, and vitamins A, B6, B12, C, D, E, and K.
Watercress achieved the top score of 100. Broccoli got 34.89, kale 49.07 and tomatoes 20.37. 
While fruits and vegetables such as oranges are thought to be healthy, many contain just one main nutrient, such as Vitamin C, whereas so-called powerhouse vegetables contain multiple nutrients.