The World Heart Federation says heart disease and stroke are the world's largest killers, claiming 17.5 million lives a year. Marking World Heart Day, the Federation says knowing the risk factors and leading a healthy active lifestyle can largely prevent people from getting these chronic, ultimately fatal diseases. Lisa Schlein reports for VOA from Geneva.

 The World Heart Federation says heart disease and stroke are commonly believed to be diseases of the wealthy. But studies show 80 percent of all deaths from these chronic illnesses occur in low and middle-income countries.

The Federation's Chief Executive Officer, Janet Voute, says cardiovascular diseases are on the increase across the African continent. Much of this, she says, is due to increased urbanization.

"When people move from rural to urban areas, there are major changes in their life, such as a decrease in physical activity, a change in dietary patterns, and increase in fast food and a decrease in fruit and vegetable consumption, for example," said Voute. "There is also an uptake of unhealthy habits such as smoking. So, a lot of society's trends are going in the wrong direction."

Voute says obesity is another major risk factor. She says Africa bears a double burden of malnutrition, that of underweight children and of overweight adults.

She says it is important to focus on improving lifestyles within an African specific context to get the message across that overweight and obesity can lead to life-threatening conditions.

"It is very difficult to suddenly say large is not beautiful. But, what is very easy to say is to say you need to be physically active, you need that for your health and you also need to know your risk, to check your risk levels," added Voute. "And, those are two initiatives that can be done in a societally appropriate context. In other words check your risk factors. Find out, in fact, if your weight is leading to high blood pressure. Find out if your overweight is leading to high cholesterol, as it is known to do."

The Geneva-based World Heart Federation says people in wealthy countries are living longer because of good medical treatment. But, it warns this progress could be set back if measures are not taken to reverse the rise in obesity among young people.

It says growing obesity among children is leading to the early onset of type-2 diabetes and to the early onset of fatty streaks in the arteries. It says these conditions can eventually lead to premature death.