Statins are medications prescribed to lower LDL cholesterol and reduce the risk of heart attack and stroke. They are the most widely used class of cholesterol-lowering drugs in the world, and they work by slowing down cholesterol production in the liver. For every 1.0 mmol/L reduction in LDL cholesterol, statins reduce the risk of major cardiovascular events like heart attack and stroke by about 21%, based on a large meta-analysis of 28 randomized trials published in The Lancet.
How Statins Lower Cholesterol
Your liver produces most of the cholesterol in your body using a specific enzyme. Statins block that enzyme, which is the key bottleneck in the cholesterol production process. When less cholesterol is made inside liver cells, those cells respond by pulling more LDL (the “bad” cholesterol) out of your bloodstream to compensate. They do this by producing more LDL receptors on their surface, essentially vacuuming up the excess cholesterol circulating in your blood.
Statins also appear to reduce the liver’s production of triglyceride-rich particles, which are another contributor to artery-clogging plaque. The net result is a measurable drop in LDL cholesterol, typically between 30% and 50% or more depending on the specific statin and dose.
Who Gets Prescribed a Statin
Statins are prescribed for two broad purposes: preventing a first cardiovascular event (primary prevention) and preventing another event in someone who already has heart disease (secondary prevention). If you’ve had a heart attack, stroke, or been diagnosed with peripheral artery disease, statins are considered essential. Guidelines don’t make age-based distinctions for these high-risk patients.
For people without existing heart disease, the decision involves weighing your overall cardiovascular risk. Factors like high LDL cholesterol, diabetes, high blood pressure, smoking, and family history all contribute. Current treatment guidelines use an LDL cholesterol level of 70 mg/dL or higher as a common threshold for considering intensified therapy. Updated 2025 ACC/AHA guidelines have pushed targets even lower for certain high-risk patients, with therapy intensification considered reasonable when LDL falls between 55 and 69 mg/dL in people with diabetes, disease in multiple blood vessels, or suspected genetic cholesterol disorders.
Benefits Beyond Cholesterol Lowering
Statins do more than just lower a number on your lab work. They have anti-inflammatory properties that help stabilize the fatty plaques inside artery walls, making those plaques less likely to rupture and trigger a clot. They also improve the function of the endothelium (the inner lining of blood vessels), reduce oxidative stress, and inhibit clot formation. Statin users consistently show lower levels of C-reactive protein, a marker of inflammation in the body.
These additional effects help explain why statins reduce cardiovascular events by more than you’d expect from cholesterol reduction alone. Researchers continue to study whether these properties could offer benefits in other areas, including immune modulation and cellular repair processes.
Common Types and Intensity Levels
There are seven statins available, and they’re grouped by how much they lower LDL cholesterol:
- High-intensity (LDL reduction of 50% or more): atorvastatin and rosuvastatin at higher doses. These are the two most potent options and the most commonly prescribed for people at highest risk.
- Moderate-intensity (LDL reduction of 30% to 49%): most statins fall into this category at their standard doses, including simvastatin, pravastatin, lovastatin, pitavastatin, and lower doses of atorvastatin and rosuvastatin.
- Low-intensity (LDL reduction under 30%): lower doses of fluvastatin, lovastatin, pravastatin, and simvastatin. These are less commonly used today since guidelines generally recommend at least moderate-intensity therapy.
Your prescriber chooses the intensity based on your cardiovascular risk profile, not just your cholesterol number.
When to Take Them
Some statins work better when taken in the evening because the body produces most of its cholesterol overnight. This matters most for shorter-acting statins like simvastatin, fluvastatin, and lovastatin. A systematic review found that evening dosing of short-acting statins lowered LDL cholesterol significantly more than morning dosing, with a difference of nearly 10 mg/dL.
For longer-acting statins like atorvastatin and rosuvastatin, the difference between morning and evening dosing is minimal. With these drugs, the best time to take them is whatever time you’ll remember consistently.
Side Effects
Muscle pain is the side effect people worry about most, and it’s the most common reason people stop taking statins. But the actual risk is lower than many people assume. In controlled trials comparing statins to a placebo, about 5% or fewer of statin users experienced muscle pain beyond what the placebo group reported. A significant portion of reported muscle symptoms may be related to the expectation of side effects rather than the drug itself.
Rhabdomyolysis, a severe form of muscle breakdown, is extremely rare. Only a few cases occur per million people taking statins.
Statins can slightly raise blood sugar levels, and the FDA requires a warning about this on statin labels. The risk of developing type 2 diabetes is small, and it’s most relevant for people who are already borderline. For most people, the cardiovascular benefit of statins substantially outweighs this modest metabolic effect.
Liver damage was once a major concern, but monitoring guidelines have relaxed considerably. The FDA now recommends checking liver enzymes at baseline and only when symptoms suggest a problem, rather than routinely. Clinically significant liver injury from statins is uncommon.
What Happens if Statins Aren’t Enough
Some people don’t reach their LDL target on statins alone, or they can’t tolerate them. In those cases, additional medications can be added. Ezetimibe, which blocks cholesterol absorption in the gut, is often the first add-on. For people at very high risk who still have elevated LDL, injectable medications called PCSK9 inhibitors can produce dramatic further reductions. Current guidelines recommend adding these if LDL remains above 70 mg/dL despite maximum statin therapy in patients with serious cardiovascular disease.