Running increases life expectancy by three years, researchers claim

* Exercise associated with improved heart attack survival
* How poor diet impairs immune function, reduces lifespan

Every hour you run extends your life span by seven hours, a new study has revealed. Scientists say that running just one hour a week is the most effective exercise to increase life expectancy.

This holds true no matter how many miles or how fast you run, the researchers claim. For those that take this advice to heart and run regularly, they say you can extend your life span by up to three years.

The study, conducted at Iowa State University, reanalyzed data from The Cooper Institute, in Texas, and also examined results from a number of other recent studies that looked at the link between exercise and mortality.

Scientists found that the new review reinforced the findings of earlier research. At whatever pace or mileage, a person’s risk of premature death dropped by 40 percent when he or she took up running.

This applied even when researchers controlled for smoking, drinking or a history of health problems such as obesity. Three years ago, the same team conducted a study that analyzed more than 55,000 adults, and determined that running for just seven minutes a day could help slash the risk of dying from heart disease.

They followed participants over a period of 15 years, and found that of the more than 3,000 who died, only one-third of deaths were from heart disease. Co-author Dr. Duck-chul Lee, a professor of kinesiology at Iowa State University, told The New York Times that after this study was released, the team was hounded with questions wondering if other activities, such as walking, were as beneficial.

Also, exercise is associated with improved survival after a heart attack, according to research published in the European Journal of Preventive Cardiology. The chances of survival increased as the amount of exercise rose.

“We know that exercise protects people against having a heart attack,” said last author Professor Eva Prescott, professor of cardiovascular prevention and rehabilitation, University of Copenhagen, Denmark. “Animal studies suggest that myocardial infarctions are smaller and less likely to be fatal in animals that exercise. We wanted to see if exercise was linked with less serious myocardial infarctions in people.”

The study included 14 223 participants of the Copenhagen City Heart Study who had never had a heart attack or stroke. Levels of physical activity were assessed at baseline in 1976-1978 and classified as sedentary, light, moderate, or high.

Participants were followed through registries until 2013. A total of 1 664 participants had a myocardial infarction, of whom 425 died immediately. The investigators compared levels of physical activity between those who died immediately from their myocardial infarction and those who survived. They found that patients who exercised were less likely to die from their myocardial infarction. There was a dose-response relationship between exercise and death from myocardial infarction. Patients with light or moderate/high physical activity levels were 32 per cent and 47 per cent less likely to die from their myocardial infarction, respectively, than sedentary patients.

Prescott said: “Patients who were sedentary were more likely to die when they got a myocardial infarction and patients who did exercise were more likely to survive. There was also a dose-response relationship, so that the odds of dying if people got a myocardial infarction declined with the level of exercise they did, reaching an almost 50 per cent reduction for those who were the most physically active.”

“One possible explanation is that people who exercise may develop collateral blood vessels in the heart which ensure the heart continues to get enough blood after a blockage,” she continued. “Exercise may also increase levels of chemical substances that improve blood flow and reduce injury to the heart from a heart attack.”

Prescott said: “This was an observational study so we cannot conclude that the associations are causal. The results need to be confirmed before we can make strong recommendations. But I think it’s safe to say that we already knew exercise was good for health and this might indicate that continuing to exercise even after developing atherosclerosis may reduce the seriousness of a heart attack if it does occur.”

Also, a new study has revealed that what you eat could be shaving years off your life. Scientists said that eating a poor diet can trigger inflammation within the body.

Foods high in sugar and fat lead to an imbalance in gut bacteria, which can cause the intestines to become leaky. This releases bacterial products that impair immune function, rapidly ageing your cells, and reducing your lifespan. The study, conducted at McMaster University in Ontario, Canada, showed researchers raising mice in germ-free conditions and comparing them to their conventionally raised counterparts.