Professor Keith Fox made his comments at a Primary Care Cardiovascular Society (PCCS) event at the Houses of Parliament. Health checks were given to a number of MPs at the event, including Conservative vice-chairman Margot James, MP for Stourbridge.
Professor Fox argued that using 10-year risk as the basis of cardiovascular risk assessments and charts limited the usefulness of risk estimates.
'The trouble is the risk charts that we've used in the past are biased,' he said. 'Biased by age.'
This bias means people in their 70s were 'inevitably' assessed as being at high risk but those under 40 were rarely judged at risk, he argued.
But Professor Fox said it was wrong to ignore the potential benefits of lifestyle change and early treatment in people who have risk factors in their 20s to 50s.
'On the current charts they would appear green (low risk),' he said. 'It would be almost impossible for them to get into other categories.'
Using lifetime risk estimates and including information about patients' lifestyle in risk assessments would help redress the age-based bias, he said.
'We are not just talking about putting them onto drugs, we are talking about lifestyle change and if we are serious about getting people initiated in lifestyle change, in increasing exercise, stopping smoking, changing diet, we have to do it as young as possible,' he added.
The PCCS event was part of a joint initiative by the British Cardiovascular Society, the PCCS and others. It includes a study of MPs' health by Neil Poulter, professor of cardiovascular medicine at Imperial College London.