Your body parts are joined in ways you never imagined. For example, did you know the length of your index finger could secretly reveal your penis size? While most of these links sound strange, knowing about them could pay dividends down the line. Here are 10 crazy body connections that just might save your life.
1. What your voice says about your height: Researchers recently found that listeners can accurately determine the relative heights of speakers just by hearing them talk. Credit the frequency of “subglottal resonance,” a sound produced in the lower airway of the lungs that gets progressively lower as height increases. Ever wonder why your tall buddies talk so low? Now you know.
2. What your eyes say about your brain: The small vessels behind your eyes could reveal how healthy your brain is, according to a recent report in Psychological Science. Researchers found that people with wider veins scored worse on IQ tests in middle age, which should give you another reason to get your peepers checked yearly.
3. What your skin says about your blood pressure: Wrinkles aren’t just a sign of aging—they could also portend ticker trouble, a study says. When researchers separated people into groups based on cardiac disease risk and analyzed the youthfulness of their skin, those with the fewest wrinkles had lower blood pressure and lower heart disease risk.
4. What your hand says about your penis: We dare you to not look at your hand after reading this! Men whose index fingers are shorter than their ring fingers tend to have bigger penises, according to 2011 Korean research. That’s because the testosterone guys get exposed to while they’re still fetuses controls both penis and finger lengths, the researchers say.
5. What your fingers say about your cancer risk: A longer index finger might also put you at a lower risk of prostate cancer, according to a study in the British Journal of Cancer.
6. What your legs say about your erection: Suffering from restless leg syndrome (RLS)? You may have more serious problems than a case of the jimmy legs, finds a recent study from Harvard Medical School. Researchers found that men who had at least five RLS episodes each month were 50 percent more likely to develop erectile dysfunction than guys without fidgety limbs. Both conditions are linked to low levels of the feel-good chemical dopamine, which might be one potential explanation.
7. What your teeth say about your mind: A 2012 study suggested your ability to chew might predict your risk of dementia. But don’t get too worried if you have trouble chomping: The researchers don’t know if mental decline leads to poor dental care and less bite force, if difficulty chewing impacts the brain, or if it’s simply just a random correlation.
8. What your pulse says about your heart: The flexibility of your aorta may soon be measured by checking the pulse in your finger, according to researchers. Your aorta is a major artery that, when stiff, can increase your risk of dying from heart attack or stroke. That could be good—and much more comfortable—news, since right now doctors have to check your pulse in the femoral artery deep in your groin to screen for aortic stiffness.
9. What your sleep says about your eyes: People with sleep apnea are almost twice as likely to develop glaucoma—an eye disease that can lead to blindness—within five years, finds research from Taiwan. When you aren’t breathing at a normal rate, the loss of oxygen triggers damage to the optic nerves, or causes abnormal levels of gases in your blood—both of which could lead to glaucoma.
10. What your lips say about your memory: If you’re one of the millions of people who get cold sores, that pesky outbreak on your lip could put you at an increased risk for Alzheimer’s and dementia, according to a study. Researchers followed adults between the ages of 59 and 79 for eight years and found that those with a higher infectious burden—meaning they’d been exposed to a higher-risk virus, such as herpes simplex virus 1 and 2—were more likely to have worse cognition.