John BailerвЂ™s May 1985 judgment of the US national cancer program as a вЂњqualified failure,вЂќ a judgment made 14В years after President NixonвЂ™s official declaration of the вЂњWar on Cancer.вЂќ Even after an additional quarter century of extensive research, researchers are still trying to determine whether cancer is preventable and are asking вЂњIf it is preventable, why are we losing the war on cancer?вЂќ In this review, we attempt to answer this question by analyzing the potential risk factors of cancer and explore our options for modulating these risk factors.Д¬ancer is caused by both internal factors (such as inherited mutations, hormones, and immune conditions) and environmental/acquired factors (such as tobacco, diet, radiation, and infectious organisms Fig. These trends of cancer incidence and death rates again remind us of Dr. In contrast, no appreciable differences in death rates for cancer have been observed in the United States ( 6).Д«y 2020, the world population is expected to have increased to 7.5 billion of this number, approximately 15 million new cancer cases will be diagnosed, and 12 million cancer patients will die ( 7). Death rates for heart disease, however, have been steeply decreasing in both older and younger populations in the USA from 1975 through 2002. According to recent statistics, cancer accounts for about 23% of the total deaths in the USA and is the second most common cause of death after heart disease ( 6). Instead of our genes, our lifestyle and environment account for 90вЂ“95% of our most chronic illnesses.Д¬ancer continues to be a worldwide killer, despite the enormous amount of research and rapid developments seen during the past decade.

For instance, the concordance between identical twins for breast cancer was found to be only 20% ( 5). In addition, studies with identical twins have suggested that genes are not the source of most chronic illnesses. Observational studies, however, have indicated that as we migrate from one country to another, our chances of being diagnosed with most chronic illnesses are determined not by the country we come from but by the country we migrate to ( 1вЂ“ 4). This statement is very important because looking to the human genome for solutions to most chronic illnesses, including the diagnosis, prevention, and treatment of cancer, is overemphasized in todayвЂ™s world. Most biology will come from the complex interaction of all the proteins and cells working with environmental factors, not driven directly by the genetic codeвЂќ ( ). They can give us useful information about the increased risk of a disease, but in most cases they will not determine the actual cause of the disease, or the actual incidence of somebody getting it. Our biology is way too complicated for that and deals with hundreds of thousands of independent factors. But in reality, those genes have very little impact on life outcomes. Everybody talks about the genes that they received from their mother and father, for this trait or the other.

In addition, we provide evidence that cancer is a preventable disease that requires major lifestyle changes.ДЄfter sequencing his own genome, pioneer genomic researcher Craig Venter remarked at a leadership for the twenty-first century conference, вЂњHuman biology is actually far more complicated than we imagine. In this review, we present evidence that inflammation is the link between the agents/factors that cause cancer and the agents that prevent it. Therefore, cancer prevention requires smoking cessation, increased ingestion of fruits and vegetables, moderate use of alcohol, caloric restriction, exercise, avoidance of direct exposure to sunlight, minimal meat consumption, use of whole grains, use of vaccinations, and regular check-ups. The evidence indicates that of all cancer-related deaths, almost 25вЂ“30% are due to tobacco, as many as 30вЂ“35% are linked to diet, about 15вЂ“20% are due to infections, and the remaining percentage are due to other factors like radiation, stress, physical activity, environmental pollutants etc. The lifestyle factors include cigarette smoking, diet (fried foods, red meat), alcohol, sun exposure, environmental pollutants, infections, stress, obesity, and physical inactivity. Only 5вЂ“10% of all cancer cases can be attributed to genetic defects, whereas the remaining 90вЂ“95% have their roots in the environment and lifestyle.

This year, more than 1 million Americans and more than 10 million people worldwide are expected to be diagnosed with cancer, a disease commonly believed to be preventable.

Modern bio study guide answers 25-1