Hi Bigbear,
In a VERY simplistic view sugar as in the sweet stuff added to cakes, biscuits etc can be thought of as a simple carbohydrate. Complex carbohydrates are generally (on food packets) just listed as carbohydrate - but our bodies treat these as an energy source in the same way as simple carbohydrates, it raises our BG levels and excess is stored as fat in our bodies very easily.
So anything that contains carbohydrates can raise our BG levels, every individual has a level of carbs that they can eat with no raise in BG levels, using a meter and testing will allow you to find out your level.
IF you wanted to go down the low-carb healthy fats route then cutting back/out high carbohydrate foods will lower your BG levels.
High carb foods are bread, pasta, potatoes, crisp, breakfast cereals, rice, pastry, sauces, wraps, biscuits, …………..
You will get used to reading labels on packets and looking at the total carbs.
BUT there are some alternatives, some sound so ridiculous but they do actually work
mashed potatoes >> mashed cauliflower or mashed celeriac
chips >> celeriac (not quite same but OK)
rice >> cauliflower rice (blitz up raw florets and then fry)
noodles >> courgettes (use a julienne peeler or a spiraliser if you have one, or a sharp knife if you're good enough)
lasagne sheets >> aubergine or leeks (open up the leek leaves)
quiche >> make without crust or use bacon as the base or use almond flour 'pastry'
pizza >> low carb base with almond flour or make oopsie bread
bread >> oopsie bread, or almond or coconut flour breads lots of recipes for bread on low carb forum
breakfast cereal >> mmm limited - recipes for breakfast options on low carb forum
Its important to have full fat products (many low fat ones add extra sugar) the fat will keep you fuller for longer and many people find it levels out the BG rise.
Its all about the testing for a while, try a single weetabix and test how much it spikes you, you might be able to eat them. we are all different.