Since the advent of gene sequencing, a number of personal genetic variants have been identified that are linked to an increased risk of certain conditions. Various gene sequences are known to be associated with a greater chance of developing heart disease, Parkinson's disease, skin cancer, Alzheimer's disease, celiac disease, Crohn's disease, and numerous other diseases. The identification of these genetic predispositions has allowed individual patients to be aware of which conditions they may be at risk of developing in the future.
Randomized controlled trials-- where patients are randomly assigned to two groups, one of which receives a treatment and one of which receives a placebo-- are the gold standard for evidence for effectiveness in behavioral interventions. However, if researchers don't report the results transparently and accurately, even a randomized controlled trial can be inaccurate.
Some people believe that cell phones cause cancer. However, there is not a lot of evidence that cell phones actually do: in order to cause cancer, something has to cause damage to DNA and there is no evidence that cell phones cause damage to DNA. However, some scientists have criticized a recent large epidemiological study of cell phones and cancer of the central nervous system.
If there's anyone who knows about organizational inefficiencies and the follies of human judgment, it's Scott Adams. For 23 years, Adams has written and illustrated the satirical comic strip Dilbert, poking fun at corporate cultures of incompetent management, perverse incentives, overhyped products, and the many other oddities and shortcomings that emerge in large systems. He's also expanded his business observations into books on ineffective bureaucracy and irrational practices.
Cancer, the uncontrolled overgrowth of cells in the body, is not a single disease, but a group of hundreds of different conditions that can affect any kind of tissue. Of each distinct disorder, there can be a number of subtypes which differ in their origin, behavior, and course of disease progression. Each type of cancer also differs in its response to chemotherapy and other treatments, and some treatments will be more or less effective than others depending on the kind of cancer. Thus, cancer therapy must be tailored to the specific disease.
Anorexia nervosa is an eating disorder involving fear of weight gain and a highly distorted body image, leading to drastic weight loss. Sufferers of anorexia often eat very little food, resulting in malnutrition and starvation, with severe consequences such as low bone mass, delayed growth, organ failure, heart problems, and even death.
Generally, people think of artherosclerosis-- the buildup of cholesterol and other fatty materials in the blood vessels that can lead to heart attacks-- as a modern disease. We drive everywhere, eat fast food and are constantly stressed; no wonder we have heart attacks.
However, a recent study suggested that artherosclerosis was common in the human past.
Malaria is a serious illness caused by a variety of parasites in the genus Plasmodium, which are transmitted between humans by mosquito bites. When a person is bitten by an infected mosquito, a small amount of parasites are transferred into the bloodstream, and these parasites then migrate to the liver and begin to reproduce. They later re-enter the bloodstream in massive quantities, causing symptoms such as fever, headache, joint pain, vomiting, anemia and convulsions. In severe cases, respiratory distress, shock, coma and death can result.
Acute lymphoblastic leukemia (ALL) is a cancer of the white blood cells, which can be fatal in a matter of weeks without treatment. While the course of the disease is rapid and severe, it can often be effectively cured: the five-year survival rates, without relapse, are over 75% for children and 30-40% for adults. However, the disease-free survival rates for adults who have relapsed ALL are very poor. The prognosis is especially grim for those whose disease has become resistant to chemotherapy, leaving them with few options for treatment.
People often make poor decisions about their health. For instance, some smokers believe they are at a lower risk of lung cancer and heart disease than the average nonsmoker, even though that is not the case. Many people show a “present bias”: they care more about today than tomorrow, which can lead them to delay eating healthy or exercising.