THE HUMAN BODY IS a lot like sausage: the more you know about it, the scarier it gets. Take the pancreas, for example. A lovely organ, but you don’t want to know what all is going on in there, trust me. Or bacteria—trillions of tiny creatures crawling over every inch of our bodies every minute of every day. And don’t even get me started on things like bad hygiene or plastic surgery or disease or what we’re doing to ourselves with our bad habits.

If you aren’t freaked out by your body, you’re not paying attention. It’s time to pay attention.

FACT 647 Antibacterial soap is no more effective at preventing infection than regular soap, and triclosan (the active ingredient) can interfere with your sex hormones.

FACT 648 The human body is home to some one thousand species of bacteria. There are more germs on your body than people in the United States.

FACT 649 A study of more than eleven thousand children determined that an overly hygienic environment increased the risk of eczema and asthma.

FACT 650 Monks of India’s Jain Dharma sect are forbidden to bathe, as bathing destroys the lives of millions of microorganisms living on the human body.

FACT 651 Ancient Egyptians treated cuts and burns with urine, as urea is known to kill fungi and bacteria.

FACT 652 England’s King Henry IV required his knights to bathe at least once in their lives—during their knighthood ceremonies.

FACT 653 Every person who enters a swimming pool contributes an average of at least 0.14 grams of fecal material to the water, usually within the first fifteen minutes of entering. And why not? They’re already peeing—might as well make it a twofer.

FACT 654 Excrement dumped from windows into the streets in eighteenth-century London contaminated the city’s water supply and forced locals to drink gin instead. Ironic, since gin has always tasted like excrement water to me.

FACT 655 A Florida seventh-grader recently won her school science fair by proving there are more bacteria in ice machines at fast-food restaurants than in toilet bowl water.

FACT 656 Sorry, but the “five-second rule” for dropped food is fiction. Bacteria can contaminate food on contact.

FACT 657 Regular teeth brushing didn’t become commonplace in the United States until it was enforced on soldiers during World War II.

FACT 658 Northern Tissue proudly introduced “splinter-free” toilet paper in 1935. Previous wiping options included tundra moss (Eskimos), a sponge with salt water (Romans) and corncobs in the American West.

FACT 659 NASA recently spent more than $23 million to design a toilet for the space shuttle that would work in zero gravity.

FACT 660 More than a third of Americans do not see a dentist every year. The American Dental Association recommends that we all see a dentist twice a year.

FACT 661 In 2009, almost half of all Mississippians did not see a dentist at all.

FACT 662 In a survey, men, African-Americans, Hispanics and seniors were all less likely than others to have visited a dentist in the past year.

FACT 682 As many as 25 percent of all women giving birth in European and American hospitals from the seventeenth through the nineteenth centuries died of puerperal fever, an infection spread by unhygienic nurses and doctors.

FACT 683 Television remote controls are the worst carriers of bacteria in hospital rooms; they spread antibiotic-resistant Staphylococcus, which contributes to the ninety thousand annual deaths from infection acquired in hospitals.

FACT 684 History has long held that President James Garfield died from an assassin’s bullet, but researchers now believe that Garfield died from a severe infection acquired from the manure-stained hands of the medical team that treated his gunshot wound.

FACT 685 Researchers in London estimate that regular hand-washing could prevent a million deaths a year.

FACT 686 In a study of sixteen elementary schools and six thousand students, regular use of hand sanitizer in the classroom decreased absenteeism due to infection by almost 20 percent.

FACT 687 More than half of healthy people have Staphylococcus aureus living in their nasal passages, throats, hair or skin.

FACT 688 The CDC reports that the spread of pinworms among children can be reduced by clipping nails and showering children immediately after they wake in the morning. Yeah right. I’d like to see them try that with my kid.

FACT 689 A study by an Australian razor company found that the ladies there associate facial hair with sexual wildness.

FACT 690 Not only is daily bathing unnecessary, but this relatively recent phenomenon strips your skin of health-promoting bacteria and oils. Do it anyway.

FACT 691 Would it kill you to floss? It might kill you not to. Studies show that you’re twice as likely to have heart disease if you have periodontal disease.

FACT 692 An estimated 6 to 12 million head lice infestations occur each year in the United States among children three to eleven years of age.

FACT 693 Yes, you can get pubic lice (“crabs”) from toilet seats, but it is extremely rare, since lice cannot live long away from a warm human body. Also, their feet are not designed to hold on to smooth surfaces.

FACT 694 British teeth may not be as straight or white as American teeth, but they are more healthy. A worldwide dental study found that the average twelve-year-old in Britain has fewer decayed and missing teeth and fewer fillings than his twelve-year-old peers in other Western countries, including America.

FACT 695 In a study of uncircumcised males, a third of foreskins contained strains of human papillomavirus (HPV), one of the most common sexually transmitted infections, and the cause of 70 percent of cervical cancers.

FACT 696 HPV can also lead to genital warts in both sexes.

FACT 697 Balanitis, an inflammation of the head of the penis, occurs most often in uncircumcised men and boys with poor hygiene.

FACT 698 Balanitis can also lead to phimosis, a condition in which the foreskin of the penis is so tight that it cannot be retracted. Phimosis makes it difficult to keep this area clean and can lead to irritation and infection.

FACT 699 The exact cause of penile cancer is unknown, but the rare disease has several known risk factors, including circumcision, smoking, HPV infection and phimosis.

FACT 700 Most cases of penile cancer occur in men over fifty.

FACT 701 The most common and effective treatment for penile cancer is surgery, including a partial or full penectomy (amputation of the penis).

FACT 702 Bacterial vaginosis, the most common type of vaginal infection, occurs more often in women who are sexually active, though it is not considered an STD.

FACT 703 Although its “fishy” smell and vaginal discharge are little more than bothersome for most women, bacterial vaginosis has been linked to pregnancy complications and infection after pelvic surgery.

FACT 704 Risk of bacterial vaginosis increases if you smoke, douche or have more than one sex partner.

FACT 705 A woman’s risk for vulvovaginal candidiasis, or vaginal yeast infection, increases with several factors, including the use of antibiotics, birth control pills, hormone replacement therapy or corticosteroids; being pregnant; douching; and wearing tight-fitting clothes.

FACT 706 The ancient Roman historian Pliny wrote that the “horrible” smell of menstrual blood drives dogs mad, and even ants will throw away grains of corn that have been touched by it. Why did their corn have menstrual blood on it? Never mind, I don’t want to know.

FACT 707 As recently as the 1920s, women were encouraged to douche with Lysol for hygiene and to prevent pregnancy.

FACT 708 Though the recent trend of pubic hair removal appears to have contributed to decreases in the occurrence of pubic lice, cases of gonorrhea and Chlamydia have increased over the same period, a correlation that may not be merely coincidental.

FACT 709 Waxing creates inflammation, which can trap bacteria beneath the skin and promote ingrown hairs and infections like staph and folliculitis.

FACT 710 You can contract a sexually transmitted disease during a bikini wax, from unclean tools or microorganisms that live in the wax and can be passed from visitor to visitor.

FACT 711 In 2007, an Australian woman with type 1 diabetes almost died of a bacterial infection she got from a bikini wax.

FACT 712 In 2009, New Jersey lawmakers considered a ban on body waxing after two women claimed they had contracted infections from the procedure. Then they thought about what a New Jersey beach would look like with unwaxed bodies and changed their minds.

FACT 735 Morgellons disease is a mysterious skin disorder characterized by disfiguring sores and crawling or stinging sensations on and under the skin.

FACT 736 Morgellons sufferers also report rashes, threads or black speck-like materials on or beneath the skin, fatigue, mental confusion, short-term memory loss, joint pain and changes in vision.

FACT 737 Infants with the rare congenital condition known as macrodactyly have toes or fingers that are abnormally large due to the overgrowth of the underlying bone and soft tissue.

FACT 738 Maple syrup urine disease (MSUD) is a genetic metabolism disorder in which the body cannot break down certain parts of proteins, causing the victim’s urine to smell like maple syrup.

FACT 739 In times of physical stress such as infection or fever, MSUD can damage the brain.

FACT 740 Jumping Frenchmen of Maine is a rare disorder characterized by an unusually extreme startle reaction to a sudden or unexpected noise or sight. It was first identified in the late nineteenth century among an isolated population of French Canadian lumberjacks in Maine and Quebec.

FACT 741 Dengue fever, a virus-based disease spread by mosquitoes, is a leading cause of illness and death in the tropics and subtropics.

FACT 742 More than one-third of the world’s population lives in areas of transmission of dengue fever. As many as 100 million people are infected each year.

FACT 743 Symptoms of infection with the dengue virus include sudden high fever, measles-like rashes, skin sensitivity, vomiting, headache, fatigue and low blood pressure.

FACT 744 Dengue fever is also characterized by acute joint and muscle aches, hence its nicknames, “break-bone fever” and “bonecrusher disease.”

FACT 745 Alice in Wonderland syndrome distorts visual perception so that nearby objects appear disproportionately tiny, as though viewed through the wrong end of a telescope.

FACT 746 Alice in Wonderland syndrome is frequently associated with migraines.

FACT 747 Victims of pica exhibit a compulsive appetite for non-edible items like clay, rocks, ash, paint, glue and even hair. The condition is thought to be caused by deficient nutrition.

FACT 748 Pica is found among the mentally ill, children and pregnant women living in poverty.

FACT 749 Ondine’s curse, or congenital central alveolar hypoventilation syndrome, is a sleep disorder that leaves victims unable to breathe spontaneously, so they must consciously will each breath or risk suffocating in their sleep.

FACT 750 Polydactylism is a congenital abnormality involving being born with too many digits, ranging from small nubs to fully formed fingers or toes.

FACT 751 While rare, polydactylism is prevalent among communities known for intermarriage, such as Philadelphia’s Old Order Amish.

FACT 752 People with Riley-Day syndrome have an insensitivity to pain, which makes them highly accident-prone since they don’t register warning signs of tissue damage like wounds or burns.

FACT 753 Half of Riley-Day patients die from their injuries by age thirty.

FACT 754 Jerusalem syndrome is a religious psychosis triggered by a visit to Jerusalem, observed since medieval times. Its victims are overcome with religious fervor and believe they are prophets or messengers of God compelled to spread the gospel and encourage sinners to repent.

FACT 755 In 1969, an Australian man suffering from Jerusalem syndrome set fire to the al-Aqsa Mosque on the Temple Mount, convinced he was the “Lord’s emissary.” Widespread rioting ensued.

FACT 756 Hypertrichosis, also called werewolf syndrome, is a congenital condition that causes hair to grow all over the body like an animal’s.

FACT 757 One famous hypertrichosis victim was JoJo the Dog-Faced Boy, aka Fedor Jeftichew, a Russian recruited by showman P. T. Barnum to tour with his circus in the nineteenth century.

FACT 758 Koro is one of a number of names for a hysterical condition known medically as genital retraction syndrome, whose victims become convinced that their genitals are disappearing into their bodies.

FACT 759 Koro syndrome can be contagious, sparking off “penis panics” like the one that overtook Singapore in 1967, when thousands of men became convinced that their penises were being stolen. Penis Panic—wasn’t that a Village People album?

FACT 760 Named after the Greek god famous for changing his shape, Proteus syndrome is a rare progressive disorder that causes disfiguring tumors and abnormal bone development.

FACT 761 The most celebrated victim of Proteus syndrome was Joseph Merrick, aka “The Elephant Man,” a grotesquely deformed man in nineteenth-century London.

FACT 762 Victims of Stendhal syndrome experience dizziness, rapid heartbeat, confusion and hallucinations when exposed to large amounts of beautiful artwork.

FACT 763 Moebius syndrome is a rare neurological disorder that leaves victims expressionless because they cannot move their faces. They are often seen sleeping with their eyes open.

FACT 764 Progeria is a rare genetic condition that causes young children to grow old prematurely. The average child born with progeria will not live past age thirteen.

FACT 765 Symptoms of progeria include a narrow, wrinkled face; hair loss; limited growth and short stature; oversized head; limited range of motion; heart disease; thinning bones; and arthritis.

FACT 766 Victims of polyglandular Addison’s disease can literally die from fear or shock, as their bodies are unable to produce adrenaline in response to alarm, but instead go into shock and begin to shut down vital organs.

FACT 767 Fournier’s gangrene is a specific form of necrotizing fasciitis (flesh-eating disease) that attacks the soft tissues of the genitalia.

FACT 768 Though Fournier’s primarily affects men, it can also develop in women due to episiotomies, abortions or hysterectomies.

FACT 769 Vulvar myiasis is a parasitic infestation of a female’s vulva caused by fly larvae, which penetrate the skin and create painful open sores.

FACT 770 Vulvar myiasis occurs predominantly in rural areas and is associated with poor hygiene.

FACT 771 Paraneoplastic pemphigus (PNP) is a rare autoimmune disease that affects skin and/or mucous membranes with painful blisters.

FACT 772 Because PNP typically occurs in association with cancer, it is frequently fatal: 90 percent of victims will die due to sepsis, multi-organ failure or the cancer that caused the disease.

FACT 773 Fields’s disease is a neuromuscular condition said to be the rarest disease in the world. Named after its only victims, Welsh twins Catherine and Kirstie Fields, the disease causes slow muscle deterioration and loss of movement.

FACT 774 Sufferers of the neurological disorder prosopagnosia, also called face blindness or facial agnosia, cannot recognize familiar faces, including their own. The illness can result from stroke, traumatic brain injury or other neurodegenerative diseases.

FACT 775 Some degree of prosopagnosia is often present in children with autism and Asperger’s syndrome and may be the cause of their impaired social development.

FACT 776 Kleine-Levin syndrome is a rare disorder that primarily affects adolescent males and is characterized by recurring periods of excessive sleep, in some cases up to twenty hours per day.

FACT 777 Macular degeneration is one known cause of Charles Bonnet syndrome, which is characterized by hallucinations following a sudden change in vision.

FACT 778 The condition may be aggravated by other circumstances such as sensory deprivation (e.g., from living alone), diminished cognitive abilities, stroke, aging, depression or bereavement (e.g., “seeing” a deceased spouse).

FACT 779 A male baby born with two penises is said to have diphallia, or penile duplication. Victims of this very rare disorder will also typically have other congenital defects, and carry a higher risk for infection and death.

FACT 780 The Fregoli delusion, or delusion of doubles, is marked by the improbable belief that different people are in fact a single person who changes appearance or is in disguise.

FACT 781 A severe form of culture shock, Paris syndrome is a condition exclusive to Japanese tourists which causes them to need psychological treatment after visiting Paris and experiencing a city quite different from their expectations.

FACT 782 Past victims of Paris syndrome include two women who thought their hotel room was being bugged, a man who became convinced he was King Louis XIV, and a woman who believed she was being attacked with microwaves.

FACT 783 Reduplicative paramnesia is the delusional belief that a location has been duplicated, existing in two or more places simultaneously, or that it has moved to another site. For example, a person may believe that he is not in the hospital to which he was admitted, but an identical-looking hospital in a different part of the country, despite this being obviously false.

FACT 784 Though rare, reduplicative paramnesia is most commonly associated with acquired brain injury, particularly simultaneous damage to the right cerebral hemisphere and to both frontal lobes.

FACT 785 In a study of America’s fifty largest metro areas, Detroit was named our most stressful city.

FACT 786 Stress is strongly associated with cardiac disease, hypertension, inflammatory diseases and compromised immune systems, and possibly to cancer.

FACT 787 Stress can break your heart, literally. Takotsubo cardiomyopathy, or “broken heart syndrome,” occurs when the bottom of the heart balloons as grief or other extreme stressors flood it with hormones.

FACT 788 Stress causes elevated levels of the hormone cortisol, which gives us a short-term boost but also suppresses the immune system, elevates blood sugar and impedes bone formation.

FACT 789 Researchers at the University of California at San Francisco found an association between high cortisol during late pregnancy in mothers and lower IQs in their children at age seven.

FACT 790 Stress during pregnancy has also been linked to children with autism.

FACT 791 Researchers at Texas A&M found that playing violent video games lowered, not increased, stress levels in subjects.

FACT 792 Studies show that the hippocampus, an area of the brain central to learning and memory, is damaged by long-term exposure to cortisol.

FACT 793 Chronic stress decreases your immune system’s response to infection and can affect your response to immunizations.

FACT 794 Studies show that HIV-infected men under high stress are more likely to progress to AIDS than those with lower levels of stress.

FACT 795 Chronic stress can impair developmental growth in children.

FACT 796 The stress of caring for a disabled spouse increases your risk of stroke significantly.

FACT 797 Men are more likely than women to develop stress-related disorders like hypertension, aggressive behavior, and abuse of alcohol and drugs.

FACT 798 The stress hormone cortisol not only causes abdominal fat to accumulate, but also enlarges individual fat cells, leading to what researchers call “diseased” fat.

FACT 799 A 2009 CNN poll revealed that the top reason for stress in most countries is money. Or, specfically, lack thereof.

FACT 800 Acoustic stress (caused by loud noises) can trigger an episode of long QT syndrome (LQTS), a disorder of the heart’s electrical system. LQTS is estimated to cause as many as three thousand deaths in the United States every year.

FACT 801 Having intercourse decreases stress hormones more than other sexual acts, including masturbation.

FACT 802 In one study, individuals who were deprived of sex had the highest blood pressure.

FACT 803 The genetic mutation that causes red hair also makes redheads resistant to anesthesia.

FACT 804 To barf or not to barf? The decision is made by a specific area of the brain known as the bilateral vomitation center, which is also the nickname for those 2-in-1 Taco Bell and KFC restaurants.

FACT 805 The average human will grow 590 miles of hair in his or her lifetime.

FACT 806 Roughly half of all false teeth have some form of radioactivity, as they once contained uranium.

FACT 832 The brain uses over a quarter of the oxygen inhaled by the human body.

FACT 833 Adult lungs have a surface area of almost seventy-seven yards—more than three-quarters of a football field!

FACT 834 Your sense of smell is ten thousand times more sensitive than your sense of taste.