Introduction

It has been known for some time that adoption of a number of core protective lifestyle behaviours, at an individual level, has a potentially large positive influence on population health. There is increasing recognition of the value of these behaviourally defined protective behaviours for health promotion and population health monitoring^1-8; advice on smoking cessation, healthy diet, physical exercise and moderation in alcohol consumption – all of which have been pillars of health education for many years. While anecdotally a perception exists, that adoption of a healthy lifestyle may impair quality of life as evidenced by the admonition “You won’t live forever, it will just feel like it”, recent evidence suggests that quality as well as quantity can be added to life through the adoption of relatively minor lifestyle changes5.

Results from previous studies reported the positive effects of a limited number of core protective lifestyle behaviours in relation to: the decreased risk in mortality1; type two diabetes⁹; hypertension; dyslipidemia^4-5; insulin resistance^10-12; and increased life expectancy¹. Other studies¹³ showed that behavioural factors are associated with substantial differences in age-related decline in functional health, and the prevalence of those in good and poor functional health in the Community.

Examining the effects of individual risk factors for chronic disease and poor physical and mental health is not a new concept; however, their combined effect on general and mental health is less well defined. The aim of this study was to examine the combined effect of practising four non-clinically defined lifestyle behaviours (being a non-smoker, being physically active, being a moderate drinker, and consuming five portions of Fruit and Vegetables (F&V) daily), on selfrated health and mental health.

The Survey of Lifestyle Attitudes and Nutrition

Using data from the Survey of Lifestyle Attitudes and Nutrition (SLÁN) 2007, a Protective Lifestyle Behaviour (PLB) score was constructed for 10,364 men and women (18+ years), and representative of the Republic of Ireland adult population (response rate 62%). The score was based on the work by by Khaw et al1. Respondents scored a maximum of four points, one point each for being physically active, consuming five or more (F&V) servings daily, a non-smoker, and a moderate drinker.

Associations between protective lifestyle behaviours and feeling healthy

The association between PLB score, self rated health and better mental health adjusted for age, sex, education and social class is shown in Table 1. For self rated health and depressive state, clear and highly significant trends were observed across the five groups of study participants. Relative to those with zero PLBs, those with four were almost seven times more likely to rate their general health as excellent / very good (OR 6.8; 95% CI [3.64-12.82]). These trends persisted even when the model was adjusted for depressive disorders. Those with four PLBs were four times more likely to have better mental health (OR 4.4; 95% CI [2.34-8.22]).

The ‘causes of the causes’ of all-cause mortality

We know from longitudinal studies that protective lifestyle behaviours increase longevity1; this study also shows that they are also associated with better self-rated health and better mental health. Conversely those who had fewer protective lifestyle behaviours, were ‘not only’ leading unhealthier lifestyles, they also perceived their overall health to be poorer and had a higher likelihood of having depression, than those with higher numbers of protective lifestyle behaviours. Our findings add to the evidence that we can achieve progress to address the ‘causes of the causes’ of all-cause mortality, mental ill-health and cardiovascular disease through small achievable lifestyle behaviour modifications. A key challenge for future research is to better understand the individual and societal determinants of health seeking behaviour. In conclusion, given the association between self-rated health, better mental health and higher numbers of protective lifestyle behaviours, we propose that the four lifestyle behaviours detailed in this study be used as outcome measures from which effectiveness of public health policy can be gauged.