On Feb. 6, 2026, a study led by researchers at Oxford Population Health reported that statins do not cause the majority of the conditions that have been listed in their package leaflets, including memory loss, depression, sleep disturbance, and erectile and sexual dysfunction, according to the most comprehensive review of possible side effects. The study was published in The Lancet.

Cardiovascular disease results in around 20 million deaths worldwide and causes around a quarter of all deaths in the UK. Statins are highly effective drugs that lower LDL (‘bad’) cholesterol levels and have been repeatedly proven to reduce the risk of cardiovascular disease. However, there have been concerns about possible side effects.

The researchers gathered data from 23 large-scale randomised studies from the Cholesterol Treatment Trialists’ Collaboration: 123,940 participants in 19 large-scale clinical trials comparing the effects of statin therapies against a placebo (or dummy tablet), and 30,724 participants in four trials comparing more intensive versus less intensive statin therapy.

They found similar numbers of reports for those taking the statins and those taking the placebo for almost all the conditions listed in package leaflets as possible side effects. For example, each year, the number of reports of cognitive or memory impairment was 0.2% in those taking the statins, but also 0.2% in those taking the placebo. This means that while people may notice these problems whilst taking statins, there is no good evidence that they are caused by the statin.

Previous work by the same researchers established that most muscle symptoms are not caused by statins; statin therapy caused muscle symptoms in only 1% of people during the first year of treatment with no excess thereafter. It has also shown that statins can cause a small increase in blood sugar levels, so people already at high risk may develop diabetes sooner.

Professor Bryan Williams, Chief Scientific and Medical Officer at the British Heart Foundation, said: ‘These findings are hugely important and provide authoritative, evidence-based reassurance for patients. Statins are lifesaving drugs, which have been proven to protect against heart attacks and strokes. Among the large number of patients assessed in this well-conducted analysis, only four side effects out of 66 were found to have any association with taking statins, and only in a very small proportion of patients.

All of the trials included in the analyses were large-scale (involving at least 1,000 participants) and tracked patient outcomes for a median of nearly five years. The trials were double-blind, meaning that neither the trial participants nor those managing the participants or leading the study knew who was receiving which treatment, to avoid potential biases due to knowledge of treatment allocation. The list of possible side effects was compiled from those listed for the five most commonly prescribed statins.