High LDL and total cholesterol are generally related to either conditions passed on in families (inherited conditions like familial hypercholesterolemia, or FH) or poor lifestyle. Unhealthy habits include:
Eating unhealthy fats and simple carbohydrates
Not exercising regularly
Being overweight or obese
In addition, you have a greater chance of heart disease or certain types of strokes if you have:
High blood pressure
Diabetes
Family history of early heart disease
Smoking or vaping
High lipoprotein(a) – also called Lp(a) or “L-P-little-A” (Lp(a) is mostly inherited or passed down in families)
Low HDL cholesterol levels (also called the "good" cholesterol)
Certain autoimmune or inflammatory conditions, such as rheumatoid arthritis, lupus, psoriasis, among others