Dictionary.com defines junk science as: “faulty scientific information or research, especially when used to advance special interests.” Junk science is going strong. Many junk science enterprises are deeply embedded in universities, the federal government and the public consciousness.
Some junk science is very bad science that is just wrong and can be easily dismissed. For example, the theories that vaccines cause autism or that power lines cause cancer. Some junk science lacks scientific support but catches the public imagination and is used by special interests to make money. An example is organic food. Organic food is food grown by methods popular prior to 1930.
The theory is that the old ways were somehow more pure and noble than modern methods. This is only carried so far. The shoppers at Whole Foods aren’t wearing homespun clothes. The government has generated regulations defining organic food and thus has bestowed legitimacy on a fad with little scientific basis. Next our representatives may be licensing psychics and promulgating standards for snake oil. If you want to have a laugh, or get some natural herbs to supposedly improve your sex life, browse the quack medicine aisle at any Whole Foods market.
Often junk science is based on distorting real science. Global warming is an example of junk science where there is a kernel of scientific truth that has been abused and beaten into a junk science edifice supporting huge money flows. There are good reasons for supposing that adding CO2 to the atmosphere might warm the Earth. The evidence is that the warming effect of CO2 is slight and not necessarily bad. (The Earth has failed to warm for over 18 years.) It is clear that adding CO2 to the atmosphere has a massive positive effect on agriculture because plants have to work hard to absorb CO2. Increased CO2 concentrations enable plants to grow faster, an incontrovertible scientific fact proved by many experiments. Global warming is promoted by entrenched scientific bureaucracies and by the huge alternative energy industry. Scientific organizations vigorously attack anyone who criticizes global warming junk science and thus threatens their members’ paychecks.
The theory Linear, No Threshold, abbreviated LNT, exerts a pervasive bad influence across many fields of public health. The theory is that if something poisons people in a certain concentration, then the poison effect will still exist for tiny concentrations of the poison, reduced by an amount proportional to the concentration of the poison. The fundamental problem is that nature is usually not linear over wide concentrations of poisons. It is invariably statistically difficult to observe the effect of small concentrations of a poison, so in particular cases the supposed LNT effect cannot be verified by collecting data. Another problem is that the human body has ways of protecting itself against low concentrations of poisons. In some instances things that are poison in high concentrations are essential nutrients at low concentrations, for example selenium or vitamin A.
The LNT approach is responsible for generalized hysteria concerning nuclear radiation. Since nuclear radiation and nuclear isotopes can cause cancer in high concentrations, using the LNT theory it can be calculated that tiny radiation levels will also cause cancer, even if the cancer cannot be detected apart from “naturally” caused cancers. Studies of atomic bomb survivors and studies of various other groups, as well as animals, exposed to radiation for various reasons, support the idea that much higher levels of radiation than currently allowed by government guidelines are harmless, or — get this — beneficial for health. See here, here, and here.
Unjustified fear of radiation has serious consequences. Doctors regularly advise patients to have MRI scans rather then less expensive CT scans so as to avoid the small amount of x-ray radiation associated with the CT scan. The government runs an expensive program to advise people to install basement ventilators to avoid exposure to radon, a naturally occurring radioactive gas emitted from the Earth in some parts of the country. The theory is that tiny doses of radon will cause lung cancer. The suspected additional lung cancer cannot be easily detected by an epidemiological study because it is a tiny theoretical increment compared to the lung cancer caused by smoking. Then there is the embarrassing fact that U.S. counties with high radon levels have less lung cancer.