Professor Kay-Tee Khaw – Supplementary written evidence (INQ0082)

Supplementary evidence following an evidence session on Tuesday 5 November.

It is important to stress that for total physical activity is the relevant measure for public health as most physical activity is not leisure time exercise but activity in the course of everyday life including occupational activity (e.g. whether an individual has a primarily sedentary occupation, standing occupation such as hairdresser, shop assistant; or active occupation e.g. manual worker) or other activities such as bicycling, stair climbing, housework and gardening.

Many studies have reported that even modest differences in physical activity have substantial health impact.

We have reported in our population study, EPIC-Norfolk, of 25,000 men and women aged 40-79 years at baseline examination in 1993-1997, followed for two decades till the present, that being even moderately inactive (occupation involving standing or more activity and no leisure time physical activity, or sedentary occupation and 30 minutes daily leisure time activity like cycling) compared to being totally inactive (sedentary occupation and no leisure time activity) was associated with about 15% lower risk of future death but also better physical and mental functional health.

Individuals who had four simple positive health behaviours (not being totally physically inactive at work or leisure time, eating five servings of fruit and vegetables a day, not smoking and moderate alcohol drinking ie between 1-14 units alcohol weekly) had a four fold difference in death rates from all cause, cardiovascular disease and cancer in the following two decades, and also better functional health compared to those individuals who did not have any of these positive health behaviours, equivalent to about 14 years in chronological age. This was independent of social class and body mass index. These were usual behaviours in free living individuals in the general community so entirely feasible: 25% of the population were practicing all four positive health behaviours. (Khaw KT et al; PLOS Medicine 2008). We have also reported that behaviours like stair climbing are positively related to good bone health and lung function.

The EPIC-Norfolk population is fairly representative of the British population apart from low ethnic representation. These are just results from one particular population study but very similar findings have been reported from many other populations. Indeed, recent studies have reported that similar positive behavioural health scores appear protective not just for survival and functional health but also appear protective for dementia and cognitive decline (Sabia S BMJ 2019).

These data from large population studies suggest that small feasible differences in health behaviours can have a measureable health impact in the general population.

11 November 2019