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10 Scientific Benefits of Kissing

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Kissing may be the most primal way we express affection with other humans. We kiss babies on their adorable chubby faces, friends on the cheeks, and lovers on the lips in demonstration of our feelings and desire for closeness. Kissing may be one of the earliest evolutionary mechanisms for social bonding. While there are plenty of obvious pleasures of smooching, there are also some remarkable health benefits, backed by science. Check out these 10 benefits of lip smacking:

1. KISSING RELEASES FEEL-GOOD HORMONES …

Kissing activates the brain’s reward system, releasing neurotransmitters like oxytocin, "the love hormone," and vasopressin, which bonds mothers with babies and romantic partners to each other. It also releases endogenous opioids, dopamine, and other helpful neurohormones to keep our moods balanced.

2. … WHICH HAVE HEALING ABILITIES.

A 2005 study in Neuroendocrinology Letters adds, "Thus, love, pleasure, and lust have a stress-reducing and health-promoting potential, since they carry the ability to heal or facilitate beneficial motivation and behavior." In other words, by reducing your stress hormones, your body can better focus on healing any physiological processes that are exacerbated by stress, and help contribute to more positive mental health and behavior.

3. IT MAKES YOU MORE ALERT.

Kissing often stimulates the release of adrenaline and noradrenaline—not only do these make you feel excited by increasing your heart rate, they make you more alert, as your body prepares for action…of any kind.

4. SMOOCH MORE FOR REDUCED STRESS …

According to affection exchange theory, as mentioned in a 2009 study in the Western Journal of Communication [PDF], physical exchanges of affection, including kissing, "buffer the individual against the physiological effects of stress." The researchers found that expressed affection, of which kissing is a prime example, was directly related to lowering the stress hormone cortisol throughout the day.

5. … WHICH MIGHT HAVE A POSITIVE AFFECT ON YOUR CHOLESTEROL.

The same study authors theorize that if affectionate behavior reduces stress, "then it is logical to predict that it will also effect improvements on physiological parameters that are exacerbated by stress" such as cholesterol. Cholesterol has a number of essential physiological functions, they write, "including maintaining membrane fluidity, producing bile, and contributing to the metabolism of fat-soluble vitamins." It’s also "largely responsible" for the production of steroid hormones, such as cortisol, aldosterone, progesterone, the estrogens, and testosterone.

6. KISSING EVEN IMPROVES ALLERGY SYMPTOMS …

Allergic responses can be aggravated by stress. Since kissing reduces stress by sending those feel-good hormones mentioned earlier to the brain, as well as alleviating cortisol, a 2003 Japanese study in Physiology and Behavior explored the relationship between the stress-lowering activity of kissing on allergic reactions. Ninety participants were evenly divided into three groups: 30 with atopic dermatitis, 30 with allergic rhinitis, and 30 in a control group. In the study, the subjects, whom the authors noted "do not kiss habitually," kissed for 30 minutes with their partner in a private room while listening to soft music. They found that at the end of their smooch sessions, the participants experienced significant relief from skin wheals (hives) and plasma neurotrophin levels (a sign of allergic reaction) associated with Japanese cedar pollen and house dust mites. In 2015, this study won an Ig Nobel prize.

7. … AND MIGHT ALSO BOOST YOUR IMMUNITY.

When you kiss someone on the lips you exchange bacteria. This can either make you sick, or it can help boost your immunity by exposing you to new germs that strengthen your immune system's ability to fight these bacteria. A 2014 study in the journal Microbiome found that couples who kissed frequently were more likely to share the same microbiota in their saliva and on the surface of the tongue. How frequently? At least nine times per day.

8. A KISS A DAY KEEPS THE DENTIST AWAY?

The act of kissing stimulates your salivary glands to produce saliva, the fluid that moistens the mouth to make swallowing easier. Saliva also helps remove cavity-causing particles that stick in your teeth after eating. So while it might be a stretch to say kissing prevents cavities, it can’t hurt.

9. IT MAY HELP YOU DETERMINE THE COMPATIBILITY OF YOUR MATE …

Perhaps the way you know you’ve found the one has nothing to do with their eyes, kind words, or the way they romance you, but very subtle cues you pick up through kissing. According to a 2013 study in the Archives of Sexual Behavior, kissing "might facilitate the subconscious appraisal of a potential mate by utilizing pheromonal cues to assess genetic … compatibility, general health, underlying genetic fitness or menstrual cycle phase and fertility." (Note the "might" here—we still haven't found evidence of human pheromones.) In fact, the authors write, in a handful of societies where mouth-to-mouth partner contact is unknown or frowned upon, such as the Mehinaku of Brazil (in fact, only 46 percent of cultures are known to kiss romantically), romantic partners still engage in "kissing traditions of close face-to-face contact involving sniffing, licking or rubbing."

10. … AND IMPROVE YOUR RELATIONSHIP SATISFACTION.

The same study authors suggest that romantic kissing, as well as other forms of physical contact, can strengthen feelings of attachment to the person you're kissing, increasing the feeling of relationship satisfaction between romantic partners. And a 2013 study in the Archives of Sexual Behavior found that more frequent kissing was linked to couples’ perceived feelings about the quality of a relationship—namely, the more kissing, the happier they were—which was not the case for more sex.

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Feeling Down? Lifting Weights Can Lift Your Mood, Too
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There’s plenty of research that suggests that exercise can be an effective treatment for depression. In some cases of depression, in fact—particularly less-severe ones—scientists have found that exercise can be as effective as antidepressants, which don’t work for everyone and can come with some annoying side effects. Previous studies have largely concentrated on aerobic exercise, like running, but new research shows that weight lifting can be a useful depression treatment, too.

The study in JAMA Psychiatry, led by sports scientists at the University of Limerick in Ireland, examined the results of 33 previous clinical trials that analyzed a total of 1877 participants. It found that resistance training—lifting weights, using resistance bands, doing push ups, and any other exercises targeted at strengthening muscles rather than increasing heart rate—significantly reduced symptoms of depression.

This held true regardless of how healthy people were overall, how much of the exercises they were assigned to do, or how much stronger they got as a result. While the effect wasn’t as strong in blinded trials—where the assessors don’t know who is in the control group and who isn’t, as is the case in higher-quality studies—it was still notable. According to first author Brett Gordon, these trials showed a medium effect, while others showed a large effect, but both were statistically significant.

The studies in the paper all looked at the effects of these training regimes on people with mild to moderate depression, and the results might not translate to people with severe depression. Unfortunately, many of the studies analyzed didn’t include information on whether or not the patients were taking antidepressants, so the researchers weren’t able to determine what role medications might play in this. However, Gordon tells Mental Floss in an email that “the available evidence supports that [resistance training] may be an effective alternative and/or adjuvant therapy for depressive symptoms that could be prescribed on its own and/or in conjunction with other depression treatments,” like therapy or medication.

There haven’t been a lot of studies yet comparing whether aerobic exercise or resistance training might be better at alleviating depressive symptoms, and future research might tackle that question. Even if one does turn out to be better than the other, though, it seems that just getting to the gym can make a big difference.

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Uncombable Hair Syndrome Is a Real—and Very Rare—Genetic Condition
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Everyone has bad hair days from time to time, but for roughly 100 people around the world, unmanageable hair is an actual medical condition.

Uncombable hair syndrome, also known as spun glass hair syndrome, is a rare condition caused by a genetic mutation that affects the formation and shape of hair shafts, BuzzFeed reports. People with the condition tend to have dry, unruly hair that can't be combed flat. It grows slower than normal and is typically silver, blond, or straw-colored. For some people, the symptoms disappear with age.

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Although there have been only about 100 documented cases worldwide, one of the world's leading researchers on the condition, Regina Betz, of Germany's University of Bonn, believes there could be thousands of others who have it but have not been diagnosed. Some have speculated that Einstein had the condition, but without a genetic test, it's impossible to know for sure.

An 18-month-old American girl named Taylor McGowan is one of the few people with this syndrome. Her parents sent blood samples to Betz to see if they were carriers of the gene mutation, and the results came back positive for variations of PADI3, one of three genes responsible for the syndrome. According to IFL Science, the condition is recessive, meaning that it "only presents when individuals receive mutant gene copies from both parents." Hence it's so uncommon.

Taylor's parents have embraced their daughter's unique 'do, creating a Facebook page called Baby Einstein 2.0 to share Taylor's story and educate others about the condition.

"It's what makes her look ever so special, just like Albert Einstein," Taylor's mom, Cara, says in a video uploaded to YouTube by SWNS TV. "We wanted to share her story with the world in hopes of spreading awareness."

[h/t BuzzFeed]

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