can phytosterols lower cholesterol

It is a well documented fact that phytosterols can lower cholesterol levels.

2-3 grams of phytosterols per day, for 3-4 weeks, can reduce LDL cholesterol by around 10% They are particularly effective for people who have high cholesterol, independently of whether they are taking cholesterol-lowering statin drugs or not They are believed to work by competing for the same enzymes as cholesterol in the gut, effectively preventing cholesterol from being absorbed

However, it’s important to realize that cholesterol levels are just a risk factor for heart disease.

Just because something has positive effects on a risk factor for a disease, it does not guarantee that it prevents the actual disease.
Phytosterols can reduce LDL cholesterol levels by around 10%, by reducing the absorption of cholesterol from the gut. However, cholesterol levels are just a risk factor, not an actual disease.