When You Feel "Chemistry" With Someone, What's Actually Going On?

iStock
iStock

We know chemistry when we feel it with another person, but we don't always know why we're drawn to one person over another. Is it just a cascade of neurotransmitters and hormones conspiring to rush you toward reproduction? Is it attraction borne of a set of shared values? Or is it bonding over specific experiences that create intimacy?

It's probably a combination of all three, plus ineffable qualities that even matchmaking services can't perfectly nail down.

"Scientists now assume, with very few exceptions, that any behavior has features of both genetics and history. It's nature and nurture," Nicole Prause, a sexual psychophysiologist and neuroscientist, tells Mental Floss. She is the founder of Liberos, a Los Angeles-based independent research center that works in collaboration with the University of Georgia and the University of Pittsburgh to study human sexual behavior and develop sexuality-related biotechnology.

Scientists who study attraction take into consideration everything from genetics, psychology, and family history to traumas, which have been shown to impact a person's ability to bond or feel desire.

THE (BRAIN) CHEMISTRY OF LOVE

Helen Fisher, a biological anthropologist at Rutgers University, Match.com's science advisor, and the author of Anatomy of Love: A Natural History of Mating, Marriage, and Why We Stray, breaks down "love" into three distinct stages: lust, attraction, and attachment. In each stage, your body chemistry behaves differently. It turns out that "chemistry" is, at least in part, actual chemistry. Biochemistry, specifically.

In the lust and attraction phases, your body is directing the show, as people can feel desire without knowing anything personal about the object of that desire. Lust, Fisher asserts in a seminal 1997 paper [PDF], is nothing more than the existence of a sex drive, or "the craving for sexual gratification," she writes. It's a sensation driven by estrogens and androgens, the female and male sex hormones, based in the biological drive to reproduce.

Attraction may be influenced less than lust by physiological factors—the appeal of someone's features, or the way they make you laugh—but your body is still calling the shots at this stage, pumping you full of the hormones cortisol, adrenaline, and dopamine, effecting your brain in a way that's not unlike the way illicit substances do.

Fisher has collaborated multiple times on the science of attraction with social psychologist Arthur Aron, a research professor at Stony Brook University in New York. Aron and his wife Elaine, who is also a psychologist, are known for studying what makes relationships begin—and last.

In a 2016 study in Frontiers in Psychology, the researchers proposed that "romantic love is a natural (and often positive) addiction that evolved from mammalian antecedents by 4 million years ago as a survival mechanism to encourage hominin pair-bonding and reproduction, seen cross-culturally today."

In the attraction phase, your body produces increased amounts of dopamine, the feel-good chemical that is also responsible for pain relief. Using fMRI brain imaging, Aron's studies have shown that "if you're thinking about a person you're intensely in love with, your brain activates the dopamine reward system, which is the same system that responds to cocaine," he tells Mental Floss.

Earlier, Fisher's 1997 paper found that new couples often show "increased energy, less need for sleep or food, focused attention and exquisite delight in smallest details of this novel relationship."

The attachment phase is characterized by increases in oxytocin and vasopressin; these hormones are thought to promote bonding and positive social behaviors to sustain connections over time in order to fulfill parental duties.

There is no hard and fast timeline for how long each phase lasts, as it can vary widely due to gender, age, and other environmental factors, Fisher writes.

Additionally, while oxytocin has long gotten the credit for being the love hormone, Prause says that scientists are now "kind of over oxytocin," because it has broader functions than simply bonding. It also plays a role in the contraction of the uterus to stimulate birth, instigating lactation, and sexual arousal; low levels have been linked to autism spectrum disorders. 

Now they're focusing on a charmingly named hormone known as kisspeptin (no, really). Produced in the hypothalamus, kisspeptin plays a role in the onset of puberty, and may increase libido, regulate the gonadal steroids that fuel the sex drive, and help the body maintain pregnancy. But Prause says there is a lot more study about the role kisspeptin plays in attraction.

CHEMICAL AND PERSONAL BONDS

Biology may explain our initial attraction and the "honeymoon" phase of a relationship, but it doesn't necessarily explain why a person's love of obscure movies or joy of hiking tickles your fancy, or what makes you want to settle down.

The Arons' numerous studies on this subject have found connection boils down to something quite simple: "What makes people attracted to the point of falling in love—presuming the person is reasonably appropriate for them—is that they feel the other person likes them," he says. 

In the process of doing research for her book How To Fall in Love With Anyone, writer Mandy Len Catron of Vancouver became her own test subject when she came across the research the Arons are most well-known for: their 36 questions, which promote bonding.

The questions were originally designed to "generate intimacy, a sense of feeling similar, and the sense that the other person likes you," Aron explains. Romantic love wasn't the goal. "It was a way of creating closeness between strangers."

The Arons first tested their questions by pairing up students during a regular class section of a large psychology course, as they related in a paper in the journal Personality and Social Psychology Bulletin. Some students were paired with someone of the same sex, while others were matched with someone of the opposite sex. Each partner then answered a series of 36 increasingly personal questions, which took about 45 minutes each. (Question 2: "Would you like to be famous? In what way?" Question 35: "Of all the people in your family, whose death would you find most disturbing? Why?") Small talk during class hadn't made them bond, but the questions made the students feel closer.

In another version of the study, heterosexual, opposite-sex pairs follow the 36-question session with four minutes of staring deeply into each other's eyes.

Catron decided to test these methods out with a casual acquaintance, Mark, over beers at a local bar one night. They were both dating other people at the time, and no one exclusively. As she answered the questions and listened to Mark's answers, "I felt totally absorbed by the conversation in a way that was unlike any of the other first dates I was having at the time with people I met online," Catron tells Mental Floss.

She was ready to skip the four minutes of soulful eye gazing, but Mark thought they should try it. "It was deeply uncomfortable, but it was also an important part of the experience," she recalls. "It's so intimate, it requires you to let your guard down."

The process instilled in Catron a deep feeling of trust in Mark and a desire to know him better. Within three months, they began dating in earnest. Now, more than three years later, they live together in a condo they bought.

The Arons' questions offer "accelerated intimacy," she says, in a time of increasingly online-driven dating experiences.

A LITTLE MYSTERY, A LOT OF SHARED VALUES

Despite all that we’ve learned, scientists may only ever be able to brush up against the edge of a true understanding of "chemistry." “We understand a fair amount about what happens when [attraction has] already occurred, but we're really bad at predicting when it will happen," Prause says. "People who try to claim magical matchmaking, or that they're going to somehow chemically manipulate an aphrodisiac or something—well good luck! Because we can't figure it out.”

And anyway, what's romance without a little mystery?

If you must have a definitive answer to the puzzle of interpersonal chemistry, Prause says to keep this in mind: "The best predictor of long-term outcomes is shared values."

This piece originally ran in 2018.

12 Facts About Diabetes Mellitus

iStock/mthipsorn
iStock/mthipsorn

Thirty million Americans—about 9 percent of the country's population—are living with diabetes mellitus, or simply diabetes. This chronic condition is characterized by sustained high blood sugar levels. In many patients, symptoms can be managed with insulin injections and lifestyle changes, but in others, the complications can be deadly. Here's what you need to know about diabetes mellitus.

1. There are three types of diabetes.

In healthy people, the pancreas produces enough of the hormone insulin to metabolize sugars into glucose and move the glucose into cells, where it's used for energy.

But people with type 2 diabetes—the most common form of the disease, accounting for about 95 percent of cases—either can't produce enough insulin to transport the sugars, or their cells have become insulin-resistant. The result is a buildup of glucose in the blood (a.k.a. high blood sugar or hyperglycemia). Type 2 diabetes typically develops in adults.

Type 1 diabetes, also known as juvenile diabetes, makes up the remaining 5 percent of chronic cases and most often develops in children and young adults. With this condition, the initial problem isn’t blood sugar levels, but insulin production: The pancreas can’t make enough insulin to process even normal amounts of glucose. The sugar builds up as a result, leading to dangerous concentrations in the bloodstream.

The third form, gestational diabetes, only afflicts pregnant people who weren’t diabetic before their pregnancy. The mother's blood glucose levels usually spike around the 24th week of pregnancy, but with a healthy diet, exercise, and insulin shots in some cases, diabetes symptoms usually can be managed. Blood sugar levels tend to return to normal in patients following their pregnancies.

2. The mellitus in diabetes mellitus means "honey sweet."

Around 3000 years ago, ancient Egyptians described a condition with diabetes-like symptoms, though it wasn't called diabetes yet. It took a few hundred years before the Greek physician Araetus of Cappodocia came up with the name diabetes based on the Greek word for "passing through" (as in passing a lot of urine, a common diabetes symptom). English doctor Thomas Willis tacked on the word mellitus, meaning "honey sweet," in 1675, building on previous physicians' observations that diabetic patients had sweet urine. Finally, in 1776, another English physician named Matthew Dobson confirmed that both the blood and urine of diabetes patients were made sweeter by high levels of glucose in their blood.

3. The cause of one type of diabetes is well understood; the other, not so much.

A person’s lifestyle is a key predictor of developing type 2 diabetes. Factors like being overweight or obese, consuming a high-calorie diet, smoking, and seldom exercising contribute to the risk. Foods and drinks that are high in sugar—soda, candy, ice cream, dessert— may contribute to hyperglycemia, but any food that’s high in calories, even if it's not sweet, can raise blood sugar levels.

In contrast to these well-established factors, medical experts aren’t entirely sure what causes type 1 diabetes. We do know that type 1 is an autoimmune disease that develops when the body attacks and damages insulin-producing cells in the pancreas. Some scientists think that environmental factors, like viruses, may trigger this immune response.

4. Family history also plays a role in diabetes risk.

If a parent or sibling has type 2 diabetes, you are predisposed to developing pre-diabetes and type 2 diabetes. Lifestyle habits explain some of these incidences, since family members may share similar diets and exercise habits. Genetics also play a role, but just because one close relative has diabetes does not mean you're destined to. Research conducted on identical twins, which share identical genes, showed that the pairs have discordant risk. Among twins in which one has type 1 diabetes, the other has only a 50 percent chance of developing it; for type 2, the risk for the second twin is 75 percent at most.

5. Racial minorities are at a higher risk for developing diabetes.

Many racial minority groups in the U.S. have a higher chance of developing type 2 diabetes. Black Americans, Latino Americans, Native Americans, Pacific Islanders, and some groups of Asian Americans are more likely to have pre-diabetes and type 2 diabetes than white Americans. This can be partly explained by the fact that some of these groups also have higher rates of obesity, which is one of the primary risk factors of type 2 diabetes. Socioeconomics may also play a role: One study shows that people with diabetes living in poverty are less likely to visit diabetes clinics and receive proper testing than their middle-income counterparts. According to another study, diabetic people without health insurance have higher blood sugar, blood pressure, and cholesterol rates than insured diabetics. Genetics, on the other hand, don’t appear to contribute to these trends.

6. Diabetes is one of the world's deadliest diseases.

With proper management, people with diabetes can live long, comfortable lives. But if the disease isn’t treated, it can have dire consequences. Diabetics make up the majority of people who develop chronic kidney disease, have adult-onset blindness, and need lower-limb amputations. In the most serious cases, diabetes leads to death. The condition is one of the deadliest diseases in the world, killing more people than breast cancer and AIDS combined.

7. Millions of Americans are pre-diabetic.

According to the CDC, 84 million adults living in the U.S. are pre-diabetic: Their blood sugar is higher than what’s considered safe, but hasn't yet reached diabetic level. In pre-diabetic patients, blood glucose levels after eight hours of fasting fall between 100 and 125 milligrams per deciliter, and diabetic levels are anything above that. People with pre-diabetes are not just at a greater risk for type 2 diabetes, but also for heart disease and stroke. Fortunately, people who are diagnosed with pre-diabetes can take steps to eat a healthier diet, increase physical activity, and test their blood glucose level several times a day to control the condition. In some cases, doctors will prescribe drugs like metformin that make the body more receptive to the insulin it produces.

8. After climbing for decades, rates of diabetes incidence are declining.

In the U.S., the rate of new diagnoses skyrocketed 382 percent between 1988 and 2014. Globally, 108 million people had diabetes in 1980, but by 2014 that number was 422 million.

But thanks to nationwide education and prevention efforts, the trend has reversed in the U.S., according to the CDC. Since peaking in 2009, the number of new diabetes cases in America has dropped by 35 percent. In that same timeframe, the number of people living with diagnosed diabetes in the U.S. has plateaued, suggesting people with the condition are living longer.

9. The first successful treatment for type 1 diabetes occurred in 1922.

Prior to the 20th century, type 1 diabetes was usually fatal. Diabetic ketoacidosis—a toxic buildup of chemicals called ketones, which arise when the body can no longer use glucose and instead breaks down other tissues for energy—killed most patients within a year or two of diagnosis. In searching for way to save children with juvenile (type 1) diabetes, Canadian physician Frederick Banting and medical student Charles Best built on the work of earlier researchers, who had demonstrated that removing the pancreas from a dog immediately caused diabetes symptoms in the animal. Banting and Best extracted insulin from dog pancreases in University of Toronto professor J.J.R. Macleod's lab. After injecting the insulin back into dogs whose pancreases had been removed, they realized the hormone regulated blood sugar levels. On January 11, 1922, they administered insulin to a human patient, and further refined the extract to reduce side effects. In 1923, Banting and Macleod received the Nobel Prize in Medicine for their work.

10. A pioneering physicist discovered the difference between type and and type 1 diabetes.

In the 1950s, physicist Rosalyn Yalow and her research partner Solomon Berson developed a method for measuring minute amounts of substances in blood. Inspired by Yalow's husband's struggle with diabetes, Yalow focused her research on insulin. Their "radioimmunoassay" technology revealed that some diabetes patients were still able to produce their own insulin, leading them to create two separate categories for the disease: “insulin-dependent” (type 1) and “non-insulin-dependent” (type 2). Prior to that discovery in 1959, there was no distinction between the two types. In 1977, Yalow won the 1977 Nobel Prize in Medicine for the radioimmunoassay, one of only 12 female Nobel laureates in medicine.

11. Making one insulin dose once required tons of pig parts.

Insulin is relatively easy to make today. Most of what's used in injections comes from a special non-disease-producing laboratory strain of E. coli bacteria that's been genetically modified to produce insulin, but that wasn't always the case. Until about 40 years ago, 2 tons of pig pancreases were required to produce just 8 ounces of pure insulin. The pig parts were typically recycled from pork farms.

12. A quarter of diabetes patients don’t know they have it.

The symptoms of type 2 diabetes can develop for years before patients think to ask their doctor about them. These include frequent urination, unexplained thirst, numbness in the extremities, dry skin, blurry vision, fatigue, and sores that are slow to heal—signs that may not be a cause for concern on their own, but together can indicate a more serious problem. Patients with type 1 diabetes may also experience nausea, vomiting, and stomach pain.

While serious, the symptoms of diabetes are sometimes easy to overlook. That’s why 25 percent of people with the illness, 7.2 million in the U.S., are undiagnosed. And that number doesn’t even cover the majority of people with pre-diabetes who aren’t aware they’re on their way to becoming diabetic.

There Are 2373 Squirrels in New York's Central Park, Census Finds

iStock/maximkabb
iStock/maximkabb

Central Park in New York City is home to starlings, raccoons, and exotic zoo animals, but perhaps the most visible fauna in the area are the eastern gray squirrels. Thanks to a team of citizen scientists, we now know exactly how many of the rodents occupy the space—approximately 2373 of them, according to a census reported by Smithsonian.

In October 2018, a group called the Squirrel Census—with help from the Explorers Club, the NYU Department of Environmental Studies, Macaulay Honors College, the Central Park Conservancy, and the New York City Department of Parks & Recreation—organized a squirrel survey across all 840 acres of Central Park. For 11 days, more than 300 volunteers staked out their sections of the park twice a day—at dawn and dusk when the crepuscular animals are most active—and noted each squirrel they spotted. They also recorded how the squirrels looked, vocalized, behaved, and reacted to humans.

The research was analyzed and presented at an Explorers Club event in New York City on June 20. All the non-peer-reviewed findings—which includes a printed report, an audio report on a vinyl 45, 37 pages of data, collectible squirrel cards, and large maps of the park and the squirrel locations—are available to purchase for $75 from the Squirrel Census website.

This isn't the first time a massive census has been conducted of a public park's squirrel population. In 2011, the Squirrel Census launched with its first survey of Atlanta's Inman Park. They've conducted satellite squirrel counts at other parks, but Central Park is just the second park the organization has investigated in person.

[h/t Smithsonian]

SECTIONS

arrow
LIVE SMARTER