One solution to the heart risk caused by obesity, although an obtuse one, is to add things to the junk food industry instead of taking away some junk food.

Researchers at Imperial College London writing in the American Journal of Cardiology suggest fast food vendors provide statin drugs free of charge.  Statins reduce the amount of unhealthy LDL cholesterol in the blood, and trial data has shown them to be highly effective at lowering a person's heart attack risk.

In the study, Dr. Darrel Francis and colleagues calculate that the reduction in cardiovascular risk offered by a statin is enough to offset the increase in heart attack risk from eating a cheeseburger and a milkshake.

One statin, simvastatin, is already available in low doses (10mg) over the counter at pharmacies without a prescription. Other statins are so far only prescribed by doctors, and limited by cost to patients at particular risk of heart attack or stroke. However, the cost of the tablets has fallen sharply in recent years (from ~£40/month to ~£1.50/month), such that the cost to the NHS of seeing a doctor is much greater than the cost of the tablet.

"It's ironic that people are free to take as many unhealthy condiments in fast food outlets as they like, but statins, which are beneficial to heart health, have to be prescribed," Dr Francis said.

Statins have among the best safety profiles of any medication. A very small proportion of regular statin users experience significant side effects, with problems in the liver and kidneys reported in between 1 in 1,000 and 1 in 10,000 people.

"Everybody knows that fast food is bad for you, but people continue to eat it because it tastes good. We're genetically programmed to prefer high-calorie foods, and sadly fast food chains will continue to sell unhealthy foods because it earns them a living.

"It makes sense to make risk-reducing supplements available just as easily as the unhealthy condiments that are provided free of charge. It would cost less than 5p per customer – not much different to a sachet of ketchup.

"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.

Citation: Emily A. Ferenczi, Perviz Asaria, Alun D. Hughes, Nishi Chaturvedi and Darrel P. Francis, 'Can a Statin Neutralize the Cardiovascular Risk of Unhealthy Dietary Choices?', The American Journal of Cardiology Volume 106, Issue 4, 15 August 2010, Pages 587-592 doi:10.1016/j.amjcard.2010.03.077