Other than the well-known risks around muscle pain and diabetes, only four of 66 other statin side-effects listed on labels liver test changes, minor liver abnormalities, urine changes and tissue swelling are supported by evidence. And the risks are very small, according to the systematic review and meta-analysis published in the Lancet. Statins have been used by hundreds of millions of people worldwide over the last three decades and are proven to reduce heart attacks, strokes and cardiovascular deaths.