Following five health habits by the age of 50 can add more than a decade of healthy life by holding off major diseases, scientists have found.
Harvard University discovered that people who ate a good diet, exercised, were a healthy body weight, did not smoke and did not drink too much, lived free of type 2 diabetes, cardiovascular disease, and cancer for far longer.
A woman who maintained all five habits by the age of 50 could expect to live to 84 years and four months before succumbing to any of the illness, compared to a woman who followed none, who would develop at least one by the age of 73 years and eight months.
Men who did not follow any of the healthy behaviours were also likely to develop one of the three conditions by 73 year and one month, but could stave off the deterioration until 81 years and six months by living well.
“Previous studies have found that following a healthy lifestyle improves overall life expectancy and reduces risk of chronic diseases such as diabetes, cardiovascular disease, and cancer, but few studies have looked at the effects of lifestyle factors on life expectancy free from such diseases,” said first author Dr Yanping Li, a senior research scientist in the Department of Nutrition at Harvard Chan School of Public Health.
“This study provides strong evidence that following a healthy lifestyle can substantially extend the years a person lives disease-free.”
In recent decades, modern medicine and scientific breakthroughs have led to a large increase in lifespan, yet it has not always been replicated in healthspan - the amount of healthy life that a person lives before the rigours of old age catch up.
To find out how healthy habits affected healthspan, researchers looked at data from two longitudinal studies involving more than 110,000 people dating back up to 34 years.
Healthy diet was defined as a high score on the Alternate Healthy Eating Index, regular exercise as at least 30 minutes per day of moderate activity, healthy weight as a Body Mass Index (BMI) of 18.5-24.9 kg/m2; and moderate alcohol intake as up to one 175ml glass of wine per day for women and up to two for men.
Lifestyle factors such as smoking, physical activity, alcohol intake, body weight and diet quality affect both overall life expectancy and likelihood of chronic diseases, but few studies have looked at how a combination of lifestyle factors may relate to life expectancy free from such diseases.
In 2018, Harvard found that men and women who adhered to all five healthy habits saw their life expectancy at 50 rise from 26 to 38 years and 29 to 43 years respectively, or an extra 12 years for men and 14 for women. But the new study is the first to show that the majority of that extra time will be spent in good health.
Women with four or five low risk lifestyle factors had 10 years and six months longer life expectancy free of the major chronic diseases than did women with zero low risk lifestyle factors, while men gained seven years and five months longer life expectancy free of major chronic diseases over those with zero low risk lifestyle factors.
Men who smoked 15 or more cigarettes a day or obese men and women with a BMI of 30 or over, had the lowest proportion of disease-free life.
“Given the high cost of chronic disease treatment, public policies to promote a healthy lifestyle by improving food and physical environments would help to reduce health care costs and improve quality of life,” said senior author and Professor of Nutrition Dr Frank Hu.