Polyphenols – a “superfamily” of diverse nutrients found in plants – promote the growth of “friendly” gut bacteria, as well as warding off the baddies. They are found in colourful plant foods, such as fruit and veg, pulses, herbs and spices... so we recommend tucking into this tuna salad, full of mixed seeds, nuts, spices and chopped veg, topped with pretty jewel-like pomegranate seeds.