I take a medication that raises cholesterol.
I have two self experiments that I can share.
It was borderline and I did the Fast800 diet - this bought it down a bit overall. I then increased my overall physical exercise levels while eating healthy with a bit of intermittent fasting. Bought it down a lot more
I think it's the combination of 3-6 months regular physical exercise plus healthy eating that had the best effect.
I then stopped exercising and have generally had quite a bad diet BUT I also swapped out bad fats for more healthy fats.
What this looks like is:
Eating fat free plain Greek yoghurt but with added nuts for healthy fats
Having around 0.5 - 1 teaspoon of extra virgin olive oil with meals
Cutting out cheese - I have it sometimes and my max portion size is 15g (sad face as I love cheese)
Cutting out butter, full stop. If I have bread, I drizzle with the olive oil and Balsamic vinegar, or smash 15g of avocado into it
What this meant is that while I was eating not brilliantly and have gained, ahem, two stone, my cholesterol only went up again by a LITTLE, but my ratio of good to bad cholesterol has improved. I now have more good than bad cholesterol, whereas before it was not a good ratio. The ratio is important - do you know your ratio?
However I have heard that for some people it's hereditary and harder to change.