"When people engage in risky behaviours like driving or smoking, they're encouraged to take measures that minimise their risk, like wearing a seatbelt or choosing cigarettes with filters. Taking a statin is a rational way of lowering some of the risks of eating a fatty meal."

Studies have shown a clear link between total fat intake and blood cholesterol, which is strongly linked to heart disease. Recent evidence suggests that trans fats, which are found in high levels in fast food, are the component of the Western diet that is most dangerous in terms of heart disease risk.

Dr Francis and his colleagues used data from a previous large cohort study to quantify how a person's heart attack risk increases with their daily intake of total fat and trans fat. He compared this with the decrease in risk from various statins, based on a meta-analysis of seven randomised controlled trials.

The results showed that most statin regimes are able to compensate for the relative risk increase from eating a cheeseburger and a small milkshake.

The researchers note that studies should be conducted to assess the potential risks of allowing people to take statins freely, without medical supervision. They suggest that a warning on the packet should emphasise that no tablet can substitute for a healthy diet, and advise people to consult their doctor for more advice.

imperial.ac