It has long been known that a number of lifestyle factors – such as not smoking, being physically active, avoiding obesity – decrease the risk of many of the “diseases of ageing,” especially cardiovascular disease and cancer. The present paper from the Nurses’ Health Study and the Health Professionals Follow-up Study is especially important as it demonstrates the joint effects of five healthy factors on disease-specific and total mortality in very large cohorts of subjects. The “healthy lifestyle factors” evaluated were (1) never smoking, (2) body mass index of 18.5 to 24.9 kg/m2, (3) ≥30 min/d of moderate to vigorous physical activity, (4) moderate alcohol intake, and (5) a high diet quality score (upper 40%). The similarity in education and other socio-economic factors of the subjects in these studies tends to reduce potential confounding by such factors.
There were more than 42,000 deaths in their cohorts during follow-up periods extending up to 34 years. The effects of these factors on subsequent risk of mortality were striking: for subjects meeting criteria for all five factors versus none, there was an 84% reduction in all-cause mortality, 65% less cancer mortality, and 82% less cardiovascular disease mortality. The overall effect was associated with 12 to 14 additional years of life after age 50 for subjects meeting criteria for all five factors.
Forum members consider this to be an excellent study, as it was based on data from very large cohorts of well-monitored subjects over many decades, with essentially full ascertainment of mortality. This study strongly suggests that the leading causes of premature death throughout the developed world are, to a large extent, preventable.
Reference: Li Y, Pan A, Wang DD, Liu X, Dhana K, Franco OH, Kaptoge S, Di Angelantonio E, Stampfer M, Willett WC. Hu FB. Impact of Healthy Lifestyle Factors on Life Expectancies in the US Population. Circulation 2018;137:00–00. (Pre-publication). DOI: 10.1161/CIRCULATIONAHA.117.032047.