Should you be taking statins? Research from Harvard University suggests if current guidelines were strictly applied, "almost all" men over 60 and women over 75 would be doing so in order to help prevent heart attack and stroke.
But the Royal College of GPs has raised the alarm saying this could lead to some older people being prescribed the drug unnecessarily. Its chairwoman, Prof Helen Stokes-Lampard said: "It is not clear that every 60-year-old man or 75-year-old woman is going to benefit from statin therapy."
What are statins?
Statins are a group of drugs designed to lower harmful cholesterol in the blood. Having too much low-density lipoprotein (LDL) cholesterol in the blood can lead to a build-up of fatty plaque in the arteries. This so-called "bad cholesterol" can cause blockages and lead to heart disease and stroke.
Statins are tablets taken once a day, and, once prescribed, will usually be taken for life.
The NHS says a review of scientific studies suggests one in 50 people who takes statins for five years, will avoid a "serious event" like a heart attack. In contrast, only one in 10,000 people taking statins will experience a "potentially dangerous" side-effect.
And they are cheap - a commonly prescribed statin, atorvastatin, taken daily costs about £2 a month per person, according to a study in the medical journal, the Lancet.
What did the research say?
New guidelines for England published in 2014 recommended statins be prescribed to anyone with a one-in-10 chance or higher of developing cardiovascular disease in the next 10 years.
A team of scientists at Harvard looked at how many of the population in England should therefore be eligible for the drug.
The recommendations from the National Institute for Health and Care Excellence (NICE) significantly increased the number of people eligible for statins.
Previous advice from the body, which provides national guidelines on health and care, said that only those with a higher than one-in-five chance of developing heart disease should be given them.
The Harvard research, published in the British Journal of General Practice, found that the updated guidance meant almost all men over the age of 60, and almost all women over the age of 75, would be considered high risk and therefore be eligible to be given statins, regardless of whether they had any other risk factors.
This is because age is one of the main factors when it comes to estimating risk of disease.
How many people should be taking statins?
The researchers estimated that, according to the guidelines, 11.8 million (37%) adults in England, aged 30-84, would be eligible for statin therapy. This would mean each GP treating almost 200 extra patients with statins.
Of these, they found more than half were not already taking the drug. But the sample of the population the researchers used was taken from a survey from 2011, before the guidelines came into place.
The researchers weren't looking at the uptake of the 2014 guidelines, but estimating what they meant for how many people would be eligible for the drug.
The study acknowledges it is unlikely that all eligible adults will receive statins. But the guidelines recommend that someone falling into the high-risk category should be having "an informed risk-benefit discussion" with their doctor, the authors point out.
A spokesman from the Royal College of GPs echoes this, saying that the NICE guidelines are, "guidelines, not tramlines, and GPs will take these into account along with any other physical, psychological and social factors potentially affecting the patient's health - as well as patient choice."
Many patients don't want to take statins, he adds, and some people who would be eligible under NICE guidelines won't visit their GP at all.
There were 67 million individual prescriptions in 2015-16, according to the NHS, but the health service does not collect data on how many individuals received the medicine.