Overweight and obese people live dangerously because they make the wrong choices in terms of food consumption and lack of physical activity. Overweight and obesity are important factors of ill-health and lead to adverse metabolic changes, including increases in blood pressure, unfavourable cholesterol levels and increased resistance to insulin. They raise the risks of coronary heart disease, stroke, diabetes mellitus, and many forms of cancer. The US Centre for Disease Control (CDC) estimates that one third of US adults are obese (79 million). The World Health Organization (WHO) quotes that obesity is killing about 220 000 men and women a year in the United States of America and Canada alone, and about 320 000 men and women in 20 countries of Western Europe.
High blood pressure and high blood cholesterol are closely related to excessive consumption of fatty, sugary and salty foods. They become even more lethal when combined with the deadly forces of tobacco and excessive alcohol drinking, which also cause a range of cancers as well as heart disease, stroke and other serious illnesses.
WHO estimates (2002) that, worldwide, high blood pressure caused 7.1 million deaths, about 13 % of global deaths. Research indicates that about 62 per cent of strokes and 49 % of heart attacks are caused by high blood pressure. High cholesterolis estimated to cause about 4.4 million deaths (7.9 per cent of total). This amounts to 18 % of strokes and 56 % of global heart disease.
The five major non-communicable diseases are heart disease, stroke, cancer, chronic respiratory diseases and diabetes. There is strong scientific evidence that healthy diets and adequate physical activity (≥30 minutes of moderate intensity physical activity, 5 days per week) play an important role in the prevention of these diseases.
However, in most countries round the world, people are not physically active and their diets are rich in high-fat, high-energy foods. Increase in obesity over the past 30 years has been paralleled by a dramatic rise in the occurrence of diabetes. Also, death increases with increasing degrees of overweight, as measured by BMI (Body Mass Index). Physical activity is an important determinant of body weight. Physical activity and physical fitness (which relates to the ability to perform physical activity) are important in preventing disease and deaths related to overweight and obesity (WHO).