It's essentially low GI, they describe it as good carb, good fat. So olive oil, nuts and seeds, avocados are all ok in measured quantities. Lots of vegetables and beans and low-fat dairy. Eggs. Lean meats for non-veggies, quorn for us veggies.
It emphasises whole foods, so no white bread or white pasta or sticky rices. But small portions of couscous, wholewheat pasta, brown rice, wholemeal bread etc. are fine. You can have wine (other alcohols not encouraged) and dark chocolate. Most fruits, including quite a few dried fruits, are ok.
It's really good for stabilising blood sugar, so excellent for anyone with insulin resistance (e.g. people with PCOS or pre-diabetes).
A typical weekday I might have:
3 sunflower and oat ryvita with natural peanut butter
bowl of fat-free natural yoghurt
mid-morning
apple
lunch
avocado, cherry tomato, spinach and low-fat mozzarella salad
mid-afternoon
sunflower seeds and sugar snap peas
dinner
black bean chilli
snacks
piece of low-fat cheesecake (homemade) or sliced pepper dipped in hummus