A brisk 20 minute walk each day could be enough to reduce an individual’s risk of early death, according to new research published today in the American Journal of Clinical Nutrition. The study of over 334,000 European men and women found that twice as many deaths may be attributable to lack of physical activity compared with the number of deaths attributable to obesity, but that just a modest increase in physical activity could have significant health benefits.
Physical inactivity has been consistently associated with an increased risk of early death, as well as being associated with a greater risk of diseases such as heart disease and cancer. Although it may also contribute to an increased body mass index (BMI) and obesity, the association with early death is independent of an individual’s BMI.
To measure the link between physical inactivity and premature death, and its interaction with obesity, researchers analysed data from 334,161 men and women across Europe participating in the European Prospective Investigation into Cancer and Nutrition (EPIC) Study. Between 1992 and 2000, the researchers measured height, weight and waist circumference, and used self-assessment to measure levels of physical activity. The participants were then followed up over 12 years, during which 21,438 of them died.
The researchers found that the greatest reduction in risk of premature death occurred in the comparison between inactive and moderately inactive groups, judged by combining activity at work with recreational activity; just under a quarter (22.7%) of participants were categorised as inactive, reporting no recreational activity in combination with a sedentary occupation. The authors estimate that doing exercise equivalent to just a 20 minute brisk walk each day – burning between 90 and 110 kcal (‘calories’) – would take an individual from the inactive to moderately inactive group and reduce their risk of premature death by between 16-30%. The impact was greatest amongst normal weight individuals, but even those with higher BMI saw a benefit.
Using the most recent available data on deaths in Europe the researchers estimate that 337,000 of the 9.2 million deaths amongst European men and women were attributable to obesity (classed as a BMI greater than 30): however, double this number of deaths (676,000) could be attributed to physical inactivity.
Professor Ulf Ekelund from the Medical Research Council (MRC) Epidemiology Unit at the University of Cambridge, who led the study, says:
This is a simple message: just a small amount of physical activity each day could have substantial health benefits for people who are physically inactive. Although we found that just 20 minutes would make a difference, we should really be looking to do more than this – physical activity has many proven health benefits and should be an important part of our daily life.”
Professor Nick Wareham, Director of the MRC Epidemiology Unit, adds:
Helping people to lose weight can be a real challenge, and whilst we should continue to aim at reducing population levels of obesity, public health interventions that encourage people to make small but achievable changes in physical activity can have significant health benefits and may be easier to achieve and maintain.”
Ekelund, U et al. Physical activity and all-cause mortality across levels of overall and abdominal adiposity in European men and women: the European Prospective Investigation into Cancer and Nutrition Study (EPIC) American Journal of Clinical Nutrition; Published Online 14 Jan 2015
About the University of Cambridge
The mission of the University of Cambridge is to contribute to society through the pursuit of education, learning and research at the highest international levels of excellence. To date, 90 affiliates of the University have won the Nobel Prize.
Founded in 1209, the University comprises 31 autonomous Colleges, which admit undergraduates and provide small-group tuition, and 150 departments, faculties and institutions.
Cambridge is a global university. Its 19,000 student body includes 3,700 international students from 120 countries. Cambridge researchers collaborate with colleagues worldwide, and the University has established larger-scale partnerships in Asia, Africa and America.
The University sits at the heart of one of the world’s largest technology clusters. The ‘Cambridge Phenomenon’ has created 1,500 hi-tech companies, 12 of them valued at over US$1 billion and two at over US$10 billion. Cambridge promotes the interface between academia and business, and has a global reputation for innovation.
About the MRC
The Medical Research Council has been at the forefront of scientific discovery to improve human health. Founded in 1913 to tackle tuberculosis, the MRC now invests taxpayers’ money in some of the best medical research in the world across every area of health. Thirty MRC-funded researchers have won Nobel prizes in a wide range of disciplines, and MRC scientists have been behind such diverse discoveries as vitamins, the structure of DNA and the link between smoking and cancer, as well as achievements such as pioneering the use of randomised controlled trials, the invention of MRI scanning, and the development of a group of antibodies used in the making of some of the most successful drugs ever developed. Today, MRC-funded scientists tackle some of the greatest health problems facing humanity in the 21st century, from the rising tide of chronic diseases associated with ageing to the threats posed by rapidly mutating micro-organisms.
About the European Prospective Investigation into Cancer and Nutrition (EPIC) Study
The European Prospective Investigation into Cancer and Nutrition (EPIC) study is one of the largest cohort studies in the world, with more than half a million (521 000) participants recruited across 10 European countries and followed for almost 15 years.
EPIC was designed to investigate the relationships between diet, nutritional status, lifestyle and environmental factors, and the incidence of cancer and other chronic diseases. EPIC investigators are active in all fields of epidemiology, and important contributions have been made in nutritional epidemiology using biomarker analysis and questionnaire information, as well as genetic and lifestyle investigations.
EPIC is supported by grants from the European Commission: Public Health and Consumer Protection Directorate 1993–2004; Research Directorate- General 2005–present; Deutsche Krebshilfe; German Cancer Research Center; German Federal Ministry of Education and Research; Danish Cancer Society; Health Research Fund of the Spanish Ministry of Health (Network of Centers of Research in Epidemiology and Public Health C03/09); the Spanish Regional Governments of Andalucia, Asturias, Basque Country, Murcia, and Navarra; Cancer Research United Kingdom; Medical Research Council, United Kingdom; the Stroke Association, United Kingdom; British Heart Foundation; Department of Health, United Kingdom; Food Standards Agency, United Kingdom; the Wellcome Trust, United Kingdom; Greek Ministry of Health and Social Solidarity and Hellenic Health Foundation; Greek Ministry of Education; Italian Association for Research on Cancer; Dutch Ministry of Public Health, Welfare, and Sports; National Cancer Registry and the Regional Cancer Registries Amsterdam, East, and Maastricht of the Netherlands; World Cancer Research Fund; Statistics Netherlands; Swedish Cancer Society; Swedish Scientific Council; Regional Government of Skane, Sweden; French League Against Cancer; the 3M Company; Mutuelle Generale de l’Education Nationale, France; Institut Gustave Roussy, France; and Institut National de la Sante et de la Recherche Medicale, France.
Image: Paul Glendell / Natural England