It is already well established that following an unhealthy lifestyle increases a person's risk of certain conditions, such as obesity, heart disease and diabetes. Now a new study has found it also greatly increases a person's risk of developing disabilities when they are older.

According to researchers from France and the UK, disability is defined as ‘difficulty or dependency in carrying out activities essential to independent living'. As the population ages, the number of people with disabilities is expected to increase significantly in the coming years, so they decided to look at the link between this issue and unhealthy behaviours.

They monitored the progress of almost 4,000 people over a 12-year period. All were aged at least 65 at the start of the study and were questioned about their lifestyle. Any incidence of disability was then recorded over the study period.

The researchers looked specifically at three levels of disability:
-Mobility - this looked at the ability to climb stairs, walk a half a mile and carry out heavy work around the house
-Instrumental activities of daily living (IADLs) - this included things like managing medication, managing money, using a telephone, using public transport, shopping, preparing meals and laundry
-Basic activities of daily living (ADLs) - this included things such as using the toilet, bathing and dressing.

The participants were considered disabled if they could not carry out at least one activity without some help.

Meanwhile unhealthy behaviours included low levels of exercise, smoking, heavy consumption of alcohol and the consumption of fruit and vegetables less than once a day.

During the study period, almost one in three participants developed a disability.
Overall, these tended to be older and were more likely to be women. They also tended to be less well educated.

However, the study also found that those who led an unhealthy lifestyle had a greater likelihood of developing a disability.

Those who exercised little or not at all had a 72% increased risk of developing a disability, irrespective of other unhealthy behaviours. Current smokers or those who had only recently quit the habit had a 26% increased risk. Those who ate fruit and vegetables less than once a day had a 24% increased risk.

Overall, people who maintained all three of these unhealthy behaviours were twice as likely to develop a disability, although no link between alcohol and disability was found.

The researchers concluded that ‘an unhealthy lifestyle, characterised by physical inactivity, unhealthy diet and smoking, is associated with a greater hazard of disability'.

However, they added that these behaviours are ‘potentially modifiable'.

Details of these findings are published in the British Medical Journal.