The Low carb High Fat lifestyle (LCHF) has made a profound difference for many people who have embraced it. Read the remarkable story of Larry Diamond in this link. He is truly inspirational.
Avocado is highly nutritious being being full of good monounsaturated fats and is very filling. I have made them a regular in my diet whether as part of a salad or to accompany main courses.
Once they have ripened at room temperature, they will keep in the fridge for about a week.
They can be made into easy guacamole by mashing one with the juice of half a lemon or lime, half a mashed clove of garlic, salt and pepper and a dessertspoon of greek yoghurt (optional).