What type of oil? There is an increasing amount of evidence to suggest that plant-based oils that are high in omega-6 (polyunsaturated) fatty acids are driving severe metabolic dysfunction. A hard and fast rule is if the plant oil can be minimally processed from the flesh(absolutely no seed oils) of the plant it’s ok but shouldn’t be heated to a very high temperature
Somewhere in this thread I’ve linked to several resources explaining the dangers of excessive polyunsaturated fat consumption. And conversely there is ample evidence explaining how switching to using tallow and especially suet(fat around the kidneys) of animals will rather quickly repair that damage
You need to get calories from somewhere, should it be from carbohydrate or fat?
high-fat-nutrition.blogspot.com
This is a very technical(to me at least), nuts and bolts blog about the dangers of seed oils. His more recent entries are about covid but the majority of the blog is nutrition related
Dr Chris Knobbe goes pretty hard against seed oils in this, and many other, presentations
carnivoremd.com
Another great podcast about seed oils
This is the doctor I’ve spoken so highly of previously. He also has several podcasts explaining why and how animal fats are superior for human health
Edited to add, after seeing pmclaine’s post. There is also plenty of available info to support that cholesterol numbers don’t mean much about your health. I know that sounds crazy but you need to get into some weeds about the numbers. Again, I’ll bang the drums for Dr Saladino here. He has several podcasts about bloodwork numbers and explaining what you should worry about, & why, and what is a load of shit