Can you clarify on oils that can be used? Olive oil? Coconut oil? Sesame seed oil?
Oils are fine in the WLC. If you are doing the challenge at the Performance level, you may not use corn or soy oils.
You are permitted to use things like canola oil, but they are not recommended.
They are in a category called "industrial seed oils" and are not particularly
good for your body. They are chemically processed to extract their oils and their chemical structure allows them to go rancid very easily.
These vegetable oils are also high in omega-6, a pro-inflammatory fatty acid. The balance of omega-3 (anti-inflammatory) to omega-6 is very important for your health and our modern diet is way off in the omega-6 direction. The inflammation this causes is at the root of many modern health issues.
Better oils include extra virgin olive oil (great for salads) and coconut oil, which
is better for cooking than for dressings. You can also get things like butter
and palm kernel oil to cook with. There is a product called MCTs (medium
chain triglycerides) that is made from coconut oil and palm kernel oil that can
be used for salad dressings.
Animal fats are also an excellent choice for cooking. They are very stable at high heat -- they don't go rancid. The saturated fats and cholesterol they contain are also critical for brain and cellular health.
Cooking sprays you may want to look at the ingredients for. If there is nothing
in them that is on the forbidden list, you're good to go.