Cancer will become world’s number one killer by 2010, as the number of people in poorer countries is expected to grow due to smoking, high-fat diets and other factors, according to a report released this week by the World Health Organization.

The report said the burden of cancer doubled globally from 1975 to 2000 and it is expected to double again by 2020 and nearly triple by 2030. There were about 12 million new cancer diagnoses worldwide this year and more than 7 million people will die from the disease. Based on current trends, the rate at which new cancers are diagnosed is expected to grow by 1 percent annually, as are deaths from the diseases.

The report estimates that the projected numbers for the year 2030 are 20 million to 26 million new diagnoses and 13 million to 17 million deaths. China, Russia and India will be the hardest hit. In other words, cancer is expected to bypass heart disease as the leading killer globally in 2010, American Cancer Society Chief Executive Officer John Seffrin said. Today, cancer accounts for about one in eight deaths worldwide. The problem is that the burden of cancer is shifting from developed countries to developing nations, where the health care systems are not so well organized and many people are underdiagnosed.

In men, lung cancer was the most common form of cancer while breast cancer was the most common type among women in new cases and deaths, according to the report. Overall, more men get cancer and die from it than women.

The major reason for this situation is smoking. The report says about 1.3 billion people smoke globally. Smoking is the major avoidable cause of death and disease worldwide. Smoking is the main cause of lung cancer, but the unhealthy habit also increases the risk of many other cancers in women, including breast, oral, pharynx, larynx, esophageal, pancreatic, kidney, bladder, uterine and cervical cancers. Seffrin noted that 40 percent of the world’s smokers live in just two nations – China and India.

Tobacco killed 100 million people worldwide last century and will kill a billion in the 21st century, unless people understand that they actually kill themselves by smoking day by day and it’s usually too late when they realize it. Also, every country in the world should take measures in order to reduce smoking. Studies have showed that countries taking such measures have fewer smokers and the overall health is better than in other countries where no such measures were taken.

Besides smoking, other factors contributing to this rise in cancer cases and deaths include high-fat diets such as fast food and decreased physical activity, in other words the western lifestyle that has gained ground in recent years. Too much alcohol, exposure to sunlight and obesity are also factors predisposing people to various forms of cancer.