Rumors Even Scientists Believe

  As the saying goes, “rumors end in the wise”, but some rumors may even be believed by scientists.
  Rumor 1: cancer screening for potential patient benefit
  of specific groups with a risk of cancer (such as lung cancer, cervical cancer and colon cancer) is for regular cancer screening might be beneficial, but not all cancer screening Both are good.
  Evidence from large randomized trials of thyroid, prostate, and breast cancer suggests that early screening is not as effective as advertised. In a 25-year national breast screening study in Canada, researchers found that annual mammograms did not reduce breast cancer mortality. This is because some tumors eventually lead to death regardless of whether they are screened and treated. At the same time, early screening has many negative effects-many cancers develop very slowly and do no harm to the human body, but many people have undergone thyroid, breast, and prostate resection surgery that were originally unnecessary.
  Although some people who have detected early cancer and have undergone resection feel they are saved, and this personal experience has fueled the spread of rumors, the benefits of early screening (curing the disease and saving people) at the group level cannot offset it Bringing risks (life or death from unnecessary treatment).
  Rumor 2: healthy antioxidants
  radical is a reactive molecule (oxidized product) when human life activities generated. In 1956, Harman, an American, proposed the mechanism of aging free radicals, and considered that free radicals are the culprits of aging and disease and are widely accepted.
  Scientists draw the inference from this theory that antioxidants (molecules that can neutralize free radicals) are good for human health, but this inference has not been supported by scientific experiments: genetically engineered genes that can produce excess free radicals The life span of rats is no different from that of normal rats; and those that have been genetically modified to produce excessive amounts of antioxidants do not live longer than normal rats.
  From this perspective, the effect of free radicals on human aging is not great. And a study on human subjects found that antioxidant health products not only have no effect, but have certain negative effects on health.
  Now, most researchers in the field of aging think that free radicals can indeed cause cell damage, but this seems to be a normal response of the body to stress.
  Rumor 3: the human brain is particularly large due to the extraordinary ability of
  the brain plays an important role in the human body, many people have extraordinary human cognitive abilities due to the huge volume of the human brain relative to the body, and it contains nerve yuan And the density of feeding glial cells.
  However, neuroscientists at Emory University in the United States say that although the human brain is seven times the size of an equivalent body animal. But the brain-to-body ratio of rats and dolphins is similar to that of humans, and some birds have even higher brain-to-body ratios. But apparently these animals did not show as extraordinary cognitive capabilities as humans. The calculation of the number of neurons in the human brain is also exaggerated: scientific reports and textbooks often say that the human brain has 100 billion neurons, but more accurate calculations show that this number is only up to 86 billion.
  Rumors 4: Use your favorite style of learning will learn better
  Many people believe that when a person learn to use their own preferred learning style will have a multiplier effect. For example, a person who likes to learn through dialogue learns best when given verbal guidance; and a person who likes to learn through vision learns most effectively using charts and images. This has enabled the relevant for-profit industry to continually craft so-called learning style books and tests. Some scientists have also fuelled this rumor, and they have cited the theory of learning styles in more than 360 papers in the past 5 years.
  However, in 2008, four cognitive neuroscientists summarized the scientific evidence on the study of learning styles. They found that only a small number of studies have rigorously proven this theory, and the “learning style” found in most studies does not actually benefit learning. Most people seem to need a combination of text and graphics to learn, not the best of the two when they appear alone.
  Rumor 5: The population is growing exponentially
  In 1798, British demographer Malthus proposed a population index growth model based on demographic data from more than a century ago. It is expected that unconstrained, exponential population growth will lead to famine and poverty. Malthus’s demographic theory once prevailed, and two centuries later it had a huge impact on China’s family planning policy.
  But looking back now, the population has never experienced exponential growth, and it is unlikely to happen in the future. The world population is currently growing at half the rate before 1965. There are currently an estimated 7.3 billion people on the planet, and it is estimated that by 2050 it will grow to 9.7 billion.
  Although people always believe that population growth will someday lead to the end of the world, according to the Food and Agriculture Organization of the United Nations, the global food production growth rate exceeds the population growth rate. At present, the world ’s grain can reach 10 to 12 billion people. Provide enough calories. Although famine and malnutrition still exist, this is a problem caused by regional wars, autocracy, and inequality. Similarly, from a global perspective, water resources are not scarce, but 1.2 billion people still live in areas with insufficient water resources.