High cholesterol is a common issue that affects more than one in five adults in the UK. It is often called a 'silent killer' because it typically doesn't present any symptoms, especially in its early stages, meaning you may have it without realising. The only way to check is by getting a blood test. Having elevated cholesterol levels without knowing can greatly heighten the risk of heart disease and stroke. But, sometimes, it can cause a few warning signs before it gets any worse - so being