10. You Can’t Swallow and Breathe at the Same Time
Virtually every other mammal can; however, human babies can only until they’re about 9 months old. Around this time the voice box drops quite low in the neck compared to other animals, which allows us to have a wide range of sounds for speech – but takes our ability to breathe and eat or drink at the same time.
9. You Have Two Brains
Just as you have neurons in your brain, you also have neurons in your gut – including neurons that produce neurotransmitters like serotonin, which is also found in your brain and is linked to mood. Your gut literally serves as your second brain, and even produces more of the neurotransmitter serotonin – known to have a beneficial influence on your mood – than your brain does.
In other words, you have two nervous systems: the central nervous system, composed of your brain and spinal cord, and the enteric nervous system, which is the intrinsic nervous system of your gastrointestinal tract. Both are actually created out of the same type of embryonic tissue. During fetal development, one part turns into your central nervous system while the other develops into your enteric nervous system.
To put this into more concrete terms, you've probably experienced the visceral sensation of butterflies in your stomach when you're nervous, or had an upset stomach when you were very angry or stressed. The flip side is also true, in that problems in your gut can directly impact your mental health, leading to issues like anxiety, depression, and perhaps even more serious neurodevelopmental disorders such as autism.
8. Loneliness is Physically Painful
Loneliness is emotionally painful for sure, but it’s physically painful as well. In fact, both loneliness and physical pain are processed in the same region of your brain, the anterior cingulate cortex. So just as you have a powerful drive to avoid causing physical pain to your body, you have a similarly powerful drive to connect with others and seek companionship – in order to avoid painful feelings of loneliness.
7. You Salivate More Before You Vomit
…And there’s a very good reason for this. Because stomach acid can be harsh on your throat and mouth, the extra saliva helps dilute the acid and rinse it away to minimize any damage caused by vomiting.
6. Sugar Can Help Your Wounds Heal
Not by eating it, of course, but rather by sprinkling it directly on the wound. Sugar is hygroscopic, which means it absorbs water that bacteria need to survive. This method has been popular among healers in Africa for generations, and it is reportedly useful for bed sores, leg ulcers, amputations and more.
A twist on this idea is to use honey, which will help draw fluid away from your wound and suppress the growth of microorganisms. Part of what gives honey its antibacterial properties is an enzyme called glucose oxidase, which the worker bees excrete into the nectar (this is found only in raw honey). Another part is the presence of beneficial Lactobacillus bacteria, found only in raw honey, which fight infection.
5. Memories Work in Mysterious Ways
Have you ever walked into a room and then forgotten why you went there in the first place? This is because your brain perceives the doorway as an “event boundary,” and memories from the room you just left are “stored” there for when you need them. This is why when you go back through the doorway into the prior room you can often remember what it is that you forgot!
4. Some Women See More Colors
Most people have three types of color receptors that allow them to see color vision. Some women have four, however, which allows them to see a wider range of colors than the average person (a small percentage of women even have five color receptors). Why women? The red and green color receptors, which can be shifted to allow for a greater range of color vision, are located on the X chromosome; blue is on the Y.
3. It Might be Healthy to Eat Boogers
Your nasal mucus might be host to small amounts of contaminants (acting as antigens) that may actually “educate” and boost your immune system when they’re consumed. So contrary to the belief that eating boogers could make you sick, it might actually help your body to fight off illnesses.
2. Most People Only Breathe Through One Nostril at a Time
Though you’ve got two nostrils, about 85 percent of people only use one at a time. But, erectile tissue in your nose slowly swells the tissue in one nostril while shrinking it in the other, so you automatically switch breathing between nostrils about every four hours.
Interestingly, body position, illness and other factors can influence which nostril you breathe from when, and, in turn, the nostril you’re breathing from can impact your health. For instance, breathing through the right nostril causes you to use more oxygen and raises your blood sugar levels.
1. Seven Miles of New Blood Vessels for Every Pound of Fat Gained
When you gain a pound of fat, your body makes seven new miles of blood vessels. This means your body must work harder to pump blood through all of these extra new vessels, which may put a strain on your heart, and may reduce oxygenation and nutrient replenishment in other tissues. Fortunately, if you lose a pound, your body will break down and re-absorb the now unnecessary vessels.