Healthy Lifestyle Factors Increase Chronic Disease-Free Life Expectancy

The average life expectancy has increased in recent years, and as the population lives longer, more older individuals live with chronic diseases such as diabetes, cancer, and cardiovascular disease (CVD). A prospective cohort study assessed how a healthy lifestyle correlates with life expectancy free of major chronic diseases. Patient data were collected from the Nurses’ Health Study (1980-2014; n=73,196) and Health Professionals Follow-Up Study (1986-2014; n=38,366). The following lifestyle factors were considered: diet, physical activity, body mass index (BMI), smoking status, and alcohol consumption.

The Alternate Healthy Eating Index (AHEI) score was used to establish diet quality; a healthy diet was defined as an AHEI score in the top 40% of the cohort. Individuals reported physical activity levels every two to four years; low risk patients were those who engaged in at least 30 minutes of moderate to vigorous activity per day (3.5 hours per week). Self-reported height and weight data were used to calculate BMI, with a healthy BMI between 18.5 kg/m2 and 24.9 kg/m2. Smoking status was self-reported and classified as never smokers (never reported smoking), current smokers (reported active smoking), and ever smokers (smoked in the past but not at the time of the survey); current smokers also reported their daily number of cigarettes smoked. Alcohol consumption was included in the food frequency section. Moderate alcohol consumption was defined as 5 g to 15 g per day for women and 5 g to 30 g per day for men.

For women who did not adopt low-risk lifestyle factors, the life expectancy free of diabetes, CVD, and cancer at age 50 was 23.7 years (95% confidence interval [CI], 22.6-24.7), compared with 34.4 years (95% CI, 33.1-35.5) for women who adopted four or five low-risk factors. For men, those who did not adopt low-risk lifestyle factors had a chronic disease-free life expectancy of 23.5 years (95% CI, 22.3-24.7) compared to 31.1 years (95% CI, 29.5-32.5) among men who adopted four or five low-risk lifestyle factors. Chronic disease-free life expectancies for men who reported being current heavy smokers as well as obese men and women constituted the lowest proportion of total life expectancy at age 50 years.