Maintaining a healthy lifestyle, which includes quitting smoking and reducing weight, can help people at high genetic risk to decrease their chance of suffering a stroke.

The study, led by researchers from the University of Cambridge in the UK, showed that the risk of stroke was 35 per cent higher among those at high genetic risk compared with those at low genetic risk, irrespective of lifestyle. However, an unfavourable lifestyle was associated with a 66 per cent increased risk of stroke compared with a favourable lifestyle, and this increased risk was present within any genetic risk category.

A high genetic risk combined with an unfavourable lifestyle profile was associated with a more than two-fold increased risk of stroke compared with a low genetic risk and a favourable lifestyle. The study, published in the journal BMJ, included 3,06,473 white men and women aged between 40 and 73 years who had no history of stroke or heart attack. 

Adherence to a healthy lifestyle was based on four factors: non-smoker, diet rich in fruits, vegetables and fish, not overweight or obese (body mass index less than 30), and regular physical exercise. Among the lifestyle factors, the most significant associations were seen for smoking and being overweight or obese, the researchers said.

Moreover, across all categories of genetic risk and lifestyle, the risk of stroke was higher in men than women. This is an observational study so no firm conclusions can be drawn about cause and effect. However, the researchers noted that their findings "highlight the potential of lifestyle interventions to reduce risk of stroke across entire populations, even in those at high genetic risk of stroke."