50 Interesting Facts about Human Hormones – Part 2

High levels of dopamine and a related hormone, norepinephrine, are released when humans are attracted to each other. These chemicals make us giddy, energetic, and euphoric, even leading to decreased appetite and insomnia, which means you actually can be so “in love” that you can’t eat and can’t sleep.

2. Some people are more sensitive to light at night due to the way the hormones controlling our 'body clocks' have been altered by artificial lighting.

3. Eating pizza boosts serotonin, an essential feel-good hormone. You can also aid serotonin production by eating nuts, seeds, and fish (for tryptophan) and yogurt (whose probiotics aid in digestion).

4. MCH neurons (Melanin-concentrating hormone-producing) in the hypothalamus are the reason why we forget our dreams. Research has shown that genetic ablation of MCH neurons increased memory performance in mice and conversely, pharmacogenetic activation of MCH neurons impaired memory.

5. The excretion of estrogen from contraceptive pills can cause high hormonal concentrations in rivers. A British Rivers study claims that these concentrations strongly correlate to the incidence and severity of intersex wild fish populations.

Up to 5% of newborns can lactate due to hormone imbalance, in a condition which is nicknamed "Witch's Milk." It is a common occurrence, associated with larger than average breast nodules, and may persist until 2 months of age in normal newborns.

7. People who don’t get enough sleep are more likely to have bigger appetites due to the fact that their leptin levels (leptin is an appetite-regulating hormone) fall, promoting appetite increase.

8. The brain releases so much dopamine during orgasms that a brain scan resembles that of someone on heroin.

9. Coffee really can make you poop. Multiple studies have shown that coffee has a laxative effect by stimulating gastrin's release, which increases activity in the colon. Some individuals experience this effect almost immediately after sipping coffee.

10. Men also have a hormonal cycle in which varying levels of testosterone affect mood, sex drive, and behaviors whilst simultaneously being responsive to cues in a woman's hormonal cycle, however, the outward signs displayed are not as evident as a woman's monthly cycle.

The oxytocin system develops during childhood and if that system doesn't develop properly, you are more prone to alcoholism and drug addiction as an adult.

12. Due to the withdrawal of hormones received in the womb some newborn girls experience menstrual bleeding from their vaginas at 2 or 3 days of age.

13. ‘Insulin Shock Therapy,’ is a practice of giving increasingly high insulin levels to psychiatric patients (mostly schizophrenics) until the patient falls into a coma for up to an hour, six days a week or for up to two years.

14. Melatonin is the hormone that’s associated with the control of our sleep-wake cycles. It evolved 700 million years ago from our tiny oceangoing ancestors that would swim to the surface of the sea at twilight and then sink into the depths of the ocean in a sleepy fall through the night.

15. Levels of the stress hormone, ‘cortisol’, which is the same ancient chemical that instructs men to fight, tends to spike about four to six weeks after men learn they are going to be fathers.

Habitual singing causes the lungs to release leptin, a protein manufactured by the body’s fat cells that are involved in the regulation of appetite. This may partially explain why opera stars tend to lean toward the heavy end of the scale.

17. The oxytocin hormone which triggers feelings of unconditional love and protection spikes when parents and children look into each other’s eyes or embrace. This spike is also seen in both human and canine brains when they interact, which shows that we love our pets in the same way as family members, and dogs return this devoted affection.

18. Chopping wood increases testosterone production by 46.8%. That’s as much as 17% higher than soccer and other studied competitive sports.

19. Research has found that the female hormone Estrogen has increased in both men and women since the 50's. Scientists have attributed this to the increased use of birth control in women and declining male hormone testosterone in men over time.

20. Insufficient sleep affects growth hormone secretion which is linked to obesity. As the amount of hormone secretion decreases, the chance for weight gain increases. It also impairs the body's ability to use insulin, which can lead to the onset of diabetes. A single night of sleeplessness can stimulate insulin resistance, a component of type 2 Diabetes, implying that sleep deprivation can be a major factor in the origin of type 2 diabetes.

Prolactin, Oxytocin, Endorphins, Epinephrine, Phenylethylamine, Testosterone, and Serotonin are released during male orgasm.

22. Losing large amounts of weight causes your body to secret more Ghrelin, the hormone that makes you hungry, so you end up gaining the weight back. Have gastric bypass, however, keeps the weight off because the amount of Ghrelin released is proportional to the overall size of your stomach.

23. The reason that both male and female genitals are darker than the surrounding skin is due to sex hormones released during puberty.

24. Melatonin levels secreted in breast milk vary depending on the time of day, helping a baby know when to sleep/wake up and thus regulate its sleep cycle. Babies who are fed formula have a harder time regulating their sleep cycle and are more prone to colic.

25. You blush because adrenaline makes your blood vessels dilate.