Roughly £260 per week for 6 people. (£130 on a Monday and £130 on a Thursday).
So by my calculations that's £187.78 per person per month. Maybe round it up to £190.
Now that is NOT just food, that also includes: bin liners, shampoo, toothpaste, handwash, body wash, conditioner, sponges, bathroom cleaner, floor cleaner, kitchen cleaner, stainless steel cleaner, washing up liquid, dishwasher tabs, dishwasher salt, dishwasher rinse aid, shaving foam, razors, face wash, medicines, plasters, fabric conditioner, washing machine tabs, anti-wrinkle day cream, anti-wrinkle night cream, vaseline, dettol wipes, toilet paper, kitchen roll, anti-perspirant, contact lens solution, oven cleaner, air freshener, and anything else of that sort that I can't think of off the top of my head.