We know that adopting a healthy lifestyle, like not smoking, exercising regularly, and keeping our weight down, yields long term benefits. But a recently concluded 35-year study is showing just how extensive these health benefits can be — and not just to our bodies, but our minds as well.
It's called the Caerphilly Cohort Study and it all got started back in 1979. It's one of several recent studies showing the importance of lifestyle on our health.
Researchers recorded the health habits of 2,235 middle-aged men aged 45 to 59 in the UK. Over the course of the next three decades, these participants were tracked for their incidences of diabetes, vascular disease, cancer, and death (a stat the researchers refer to as "all cause mortality" — which includes everything from death-by-disease through to getting hit by a streetcar).
To monitor healthy lifestyles, the researchers tracked five specific behaviors:
- Regular exercise (described as walking two or more miles to work each day, or cycling ten or more miles to work each day, or 'vigorous' exercise described as a regular habit)
- Low body weight (a BMI of 18 to under 25 Kg/m2)
- Healthy diet (three or more portions of fruit and/or vegetables a day was accepted as 'healthy', together with less than 30% of calories from fat)
- Low alcohol intake (defined as three or fewer units per day, with abstinence not treated as a healthy behaviour)
After analyzing the results, the researchers discovered that participants who followed four or five of these lifestyle habits experienced — get this — 70% fewer instances of diabetes, heart disease and stroke, when compared to those who followed none. Whoa.
In terms of specifics, the numbers broke down like this: 50% reduction in diabetes, 50% in vascular disease (equating to delayed onset of 12 years and an added six years of life!), and 60% for all-cause mortality.
But here's where it gets even more fascinating: The same group — the 4/5 or 5/5 people — experienced a 60% decline in dementia and cognitive decline. And surprisingly, exercise was the strongest factor. Actually, if you're a regular reader of io9, this won't really surprise you. The researchers say this can be attributed to the stimulation of vascular metabolic and emotional pathways.
Strangely — and even the researchers were taken aback by this — the only health behavior that influenced the onset of cancer was non-smoking. That's actually quite upsetting. If we're to accept these results, it means that all that exercise and all that healthy eating you're doing is contributing squat as far as cancer is concerned.
Speaking through an official release, Principle Investigator Professor Peter Elwood had this to say about the findings:
The size of reduction in the instance of disease owing to these simple healthy steps has really amazed us and is of enormous importance in an aging population. What the research shows is that following a healthy lifestyle confers surprisingly large benefits to health – healthy behaviours have a far more beneficial effect than any medical treatment or preventative procedure.
Taking up and following a healthy lifestyle is however the responsibility of the individual him or herself. Sadly, the evidence from this study shows that very few people follow a fully healthy lifestyle. Furthermore, our findings reveal that while the number of people who smoke has gone down since the study started, the number of people leading a fully healthy lifestyle has not changed.
Elwood is referring to the fact that less than 1% of people in Wales (a location chosen because of its highly representative social class distribution) followed a completely healthy lifestyle.
Of course, there could be a ton of other factors, or residual confounders, other than the five listed by the researchers. Like socioeconomic status, education, or marital status. "Nevertheless, our findings confirm that there is a substantial health benefit associated with a healthy lifestyle," conclude the researchers in the study.
Moreover, the researchers admit that the study was limited — but limited in way that the full impact of healthy lifestyles had to be underestimated owing to the small numbers of men adhering to all five healthy behaviors. In other words, the 4/5 and 5/5 people may have actually benefited even more than the study suggests.
Read the entire study at PLOS ONE: "Healthy Lifestyles Reduce the Incidence of Chronic Diseases and Dementia: Evidence from the Caerphilly Cohort Study".