Adult Films May Boost Sex Life

You won’t have to feel guilty the next time you lock the door, turn off the lights, and get under the covers to watch an X-rated movie. Watching pornography may actually be a good thing for you, especially for your sex life. According to a recent studypublished in the journal Sexual Medicine, at least 40 minutes of porn twice a week, which is the equivalent of three months of your lifetime, can boost your sex drive and your overall desire to have sex.

The link between porn consumption and its effect on genuine sexual interactions has received mixed reviews. The availability of free Internet porn is believed to have contributed to a decline in relationship sexual satisfaction and even marriage among young men. A 2014 studypublished in the Eastern Economic Journal found free Internet porn has not only led to a decline in young adult males who are married, but could actually be contributing to the trend. The allure of “easy sex” and stimulating variety from virtual pleasure allows men to have endless access to sex every day at any time of the day.

Other psychologists beg to differ, however, and suggest watching porn can enhance sexual enjoyment and happiness, especially if you’re in a relationship. Couples who engage in watching porn together and have a mutual agreement on what’s considered to be acceptable porn are more likely to have thriving relationships because of their level of honesty and communication.

Often, watching can stimulate ideas, themes, and scenarios that can elicit spontaneity and adventure for the couple,” Dr. Fran Walfish, Beverly Hills psychotherapist, author, and expert panelist on WE TV’s Sex Box, previously told Medical Daily.  

Nicole Prause and Jim Pfaus, authors of the study from UCLA and Concordia University, sought to test the effect of watching erotica sex drive and erectile function in a cohort of 280 male volunteers in their 20s, of which 127 had regular partners. The men were asked to record their own porn viewing habits while tracking their libido. All of the men reported having spent from zero to 25 hours per week watching sex films, and they also completed questionnaires measuring levels of sexual desire. They also viewed films in the lab that showed a man and woman having consensual vaginal intercourse and then reported their level of sexual arousal.

The findings revealed there is a positive correlation between the amount of time spent viewing porn and the desire to have sex. Men who watched no porn were found to score just over 40 on the researchers' arousal matrix. Meanwhile, men who did watch porn scored over 50. Those who watched more than two hours of porn per week were found to have the highest level of arousal, meaning they had more desire for masturbation and sex with a partner.

While one could object that this was expected since they like sex films, the result is important because clinicians often claim that men get desensitized by watching these films," said Prause, in the press release. "They are responding more strongly to very vanilla erotica than the guys for whom the films are more novel. While this association doesn't establish a cause, it proves viewing erotica at home is not desensitizing and perhaps even sensitized the men to respond more strongly."

The researchers also looked at instances of erectile dysfunction based on the International Index of Erectile Function, a questionnaire that requires men to rate their experience with erectile function. They wrote: "erectile functioning with a partner was not related to the hours of VSS (visual sexual stimuli) viewed weekly." This contradicts previous literature which suggests porn leads to problems in the bedroom. "The erectile dysfunction is most likely caused by the same issues that have been known for some time, such as performance anxiety, poor cardiovascular health, or side-effects from substance abuse,” said Pfaus.

Prause and Pfaus believe it would be useful to assess erection maintenance directly in the future to get to the root of the problem, not porn.

Until then, it seems science has given the “OK” to healthily indulge in porn and give yourself a helping hand.

causes of memory loss

Memory is key to both the flow and betterment of your life. Knowledge gained from recollection of the past helps you move toward the future you hope to create. While you are probably aware that memory loss can be caused by a concussion or surgery, a stroke or a brain tumor, you may not know some less obvious reasons why you may be finding it difficult to remember the turn off for the shortest drive home.

Prescription Drugs

Prescription sleeping pills are possibly the worst offenders when it comes to memory deficits. Ambien and Lunesta, among the most popular sleep meds, are known to cause some users to sleep walk, others to sleep eat, and others to sleep drive. “When we study the brain of someone in a drug-induced sleep, there is little resemblance to true sleep,” writes Dr. Kirk Parsley in Integrative Health Review. “In fact, we see a pattern similar to the type of unconsciousness that is associated with a coma or passing out from excessive alcohol consumption.” By causing unconsciousness, sleeping pills not only rob you of the benefits of sleep, they also impact your abilities to recall.

And then there are the benzodiazepines, which are often prescribed for anxiety disorders, agitation, and muscle spasms, and include Valium (diazepam), Xanax, (alprazolam), Librium (chlordiazepoxide), and Ativan (lorazepam). While they may help to calm and to ease the nerves, these drugs work by suppressing neurotransmitters and brain regions key to the transfer of your memories from the short-term to the long-term storage bin. Understanding the negative effects on memory, pharmacists recommend limited courses of benzodiazepines for brief durations.

Finally, cholesterol-lowering medications, commonly referred to as statins, may also contribute to your inability to remember the past. In fact, the Food and Drug Administration now requiresmemory loss be listed as a side effect on the labels for Lipitor (atorvastatin), Zocor (simvastatin), Crestor (rosuvastatin) and other statin drugs. Quite simply, cholesterol is necessary for learning and thinking, and along with lowering the levels in your blood, these drugs are also working to reduce the levels in your brain, ultimately eroding the connections between nerve cells.

Migraine Headaches

Migraine headaches are severe and long-lasting and may include nausea, vomiting, sensitivity to light, and a throbbing pain felt on just one side of the head. Arecent study, which investigated the impact of migraine on memory loss following an attack, showed how migraine patients suffered impairment in global-visual processing in the two days following an attack, but not in attention or working memory. Following a migraine, some patients will experience complete amnesia lasting hours; this specific neurological disorder is known as transient global amnesia. Another study conducted by Taiwanese researchers found migraines to be associated with a higher risk of dementia; specifically, the cumulative incidence of dementia was 1.48 percent greater among participants suffering migraine compared to those without these headaches.

Stress

Stress can cause weight gain and higher blood pressure, and for many people it is the road leading to diabetes and heart disease. Stress is everywhere and at times stress is no where. We sometimes feel it even without the pressure of a deadline, even when we ignore the frowns of our boss. Now, a new studyconducted in mice finds high levels of cortisol, the infamous “stress hormone,” may be one cause for short-term memory loss. In the brains of the mice, cortisol ate away at synapses in the prefrontal cortex, an area implicated in short-term memory. And, the problem worsened with age; the longer the synapses endured exposures to cortisol, the greater the short-term memory loss suffered by the animals. However, the researchers also found a positive spin to this unhappy news. Some of the older mice with low cortisol levels displayed little memory loss, suggesting replenishment of cortisol might someday aid those with failing memories.

Blood Type

People whose blood type is AB are known to be at greater risk of blood vessel-related conditions due to the generally higher levels of clotting protein VIII. Now, a three-year study finds people with type AB blood are twice as likely to experience memory problems as people with type O blood. After examining a group of 495 participants who had developed thinking or memory problems, the researchers compared them to 587 age-matched people with no cognitive problems. Those with an AB blood type were 82 percent more likely to experience difficulties with everyday memory recall, language, and attention, and a higher percentage were found in the dementia group than in the general population. While more study is needed to confirm the results, these findings may not surprise those who understand how memory loss is linked to blood flow to the brain; any blood vessel-related conditions associated with the AB blood type would lead to less optimal flow to brain cells and ultimately result in cognitive impairment. Again: it’s much too early to say people in the AB blood group have a slightly higher risk of dementia.

Vitamin B12

We need vitamin B12 to make red blood cells, nerves, and even DNA, however, our bodies cannot produce this precious vitamin on their own. Instead, we must absorb it through food, including meat, eggs, poultry, dairy products, and other foods from animals, or from supplements. If we fail to get enough vitamin B12, a severe deficiency may lead to memory loss and one day even dementia. Three in every 100 adults over the age of 50 have a seriously low B12 level, while up to one fifth may have a borderline deficiency, according to estimates based on the National Health and Nutrition Examination Survey. Though notgetting enough B12 may lead to memory deficits and mental decline, getting extra B12 unfortunately does not reverse a tendency toward dementia. Prevention, though, is a plenty good reason for asking your doctor to check your B12 levels.

Why Stress Responses Can Cause Your Hair To Stand On End

When was the last time your hair stood up on the back of your neck? Ever wonder why?

Goosebumps and your neck hair standing on end are sibling responses, so to speak, caused by fear, low temperatures, stress, or other extreme emotions or conditions. They are both caused by contractions of miniature muscles (attached to each hair) that create a shallow depression on the skin surface. In turn, the surrounding area protrudes causing both bumps on your skin and the hair on your arms and neck to stand on end. Each of these physiological phenomena is inherited from our animal ancestors, according to George A. Bubenik, a physiologist and professor of zoology at Ontario’s University of Guelph, writing inScientific American.

In animals with a thick hair coat, this response serves any number of purposes. It often occurs as a response to cold and so helps warm the body. Elevated hair expands the layer of air that naturally insulates the body. The response to cold, then, helps an animal’s body more effectively retain heat. In other situations, say, a cat being attacked by a bigger feline, the raised hair, together with an arched back, makes the cat appear bigger and scarier to a predator. Threatened equals threatening, courtesy of a little biophysiology.

However, we humans lack a hair coat, so this physiological response is useless, most people would say. Still, it could be argued that this unusual physical response raises our awareness of possible danger — helps us feel the fear, so to speak.

Underneath the mechanical muscle contraction, after all, is the release of a stress hormone. Adrenaline, also called epinephrine, is produced in two beanlike glands that sit atop the kidneys and released into the bloodstream. Not only does this hormone cause the contractions of skin muscles, it also causes the cascade of physiological responses we fondly refer to as flight-or-fight. The suddenly racing heart, the feeling of "butterflies" in the stomach, trembling hands, sweaty palms — all of these signs tell us that adrenaline is coursing through our veins. In practical terms, the sudden flood of this hormone increases our muscle strength. (No one is joking about the fight part of the equation.)

What is strangest about this hormone, though, is it also may be released during our happiest moments. Sometimes we tremble with joy as we do with fear. "There is a thin line between pleasurable and unpleasurable stress," Bubenik said. Since the brain clearly does not distinguish between danger and delight, we must assume that is a job for the soul.

Men’s Chewing Patterns Differ From Women’s

It’s likely there’s someone in your family who's known as the food vacuum, or the garbage disposal. The brother who’ll clean everything off his plate within minutes and sometimes seconds.

To some, scarfing down food is natural, and the ability is often associated with growing teenage boys or grown men more so than women. A group of researchers from Semyung University in South Korea wanted to better understand what the chewing and eating differences were between men and women, and how chewing patterns had an effect on weight. In their study, which was published in the journal Physiology & Behavior, they found that men and women had vastly different chewing “performances,” and that obesity also had an effect on chewing and eating behaviors.

While we do it every day without thinking about it, chewing has an important role as the first step in the digestive process. Chewing is sometimes referred to as mastication: the process of teeth grinding down food to increase the surface area of food, making it more easily broken down by enzymes.

The study was partially motivated by the authors’ desire to investigate obesity therapies, such as modified eating behaviors. The way you chew your food, and how fast you do it, can have quite an impact on how much food you consume in a given amount of time. Generally, people who are obese often have much faster chewing tendencies, as well as a bigger bite size, than people of normal weight. Some other research, interestingly, has shown that eating more slowly may actually be linked to weight loss: since it prolongs the regulation of ghrelin, also known as the hunger hormone, and helps you feel more satisfied from less food.

Twenty-four males and 24 females participated in the study, and had electrodes attached to their jaw muscles. Each participant was given 152 grams of boiled white rice, and asked to eat it while the researchers measured their bite size; the quantity of food, in grams, ingested every minute; the number of chews per mouthful, and the total number of chews, among other things. The authors found that males were more likely to chew faster and have a bigger bite size than females, while females were more likely to chew more times per gram of food, making their meals last longer.

While the study found a significant difference between the chewing patterns of men and women, it did not fully explain whether chewing was directly related to weight gain or weight loss. Sure, chewing quickly and swallowing huge amounts of food in a short period of time might be a factor in obesity — but so are a myriad of other things like physical inactivity, depression, and genetics. The researchers concluded that they’ll need more research, but they hope that at some point the information will be used to develop obesity therapies.

“[C]hewing influences a range of cognitive and emotional functions, which are different in both under- and overweight patients compared with normal weight controls,” the authors wrote in their conclusion. “In addition, the modulation of eating behavior through chewing can be used as specific feedback to normalize food intake and, thus, normalize body weight.”

WHO Calls For Reduction In Medically Unnecessary C-Sections

Roughly 19 out of every 100,000women die each year from giving birth to their child. That’s a lot, but not nearly as many as there were about a century ago, whenover 600 women were dying each year. Caesarean sections can take most of the credit for this drastic reduction in maternal deaths; children who might have been birthed in the wrong position no longer put their mothers at risk of death. But somewhere along the line, the procedure went from being medically necessary to elective — a trend the World Health Organization said on Friday should be reversed.

After 12 years of rising C-section rates, the number of procedures leveled off in 2009, with about a third of all U.S. mothers undergoing the operation — they’ve remained about the same since. Still, C-sections are one of the most common surgeries performed around the world, with rates still rising in middle- and high-income countries. Hoping to reduce these rates, WHO advised in a statement that we all make an effort to reduce rates of medically unnecessary C-sections, approaching them instead on a case-by-case basis.   

The reason for reducing C-section rates, WHO says, is because there’s a threshold for when the procedure might cause more harm than good. Recent studies have put that threshold at about 10 percent; as rates rise in that direction, the number of maternal and newborn deaths in the population decreases. But once they go over, there’s no additional benefit.

C-sections are effective in so many situations, allowing both mother and child to live when the child is found to be in an awkward position; when a vaginal birth isn’t possible; and when the baby is distressed, among other scenarios.

But it’s still a major surgery with its own risks for complications, all of which occur more often than when undergoing a vaginal birth. These can include bladder and uterus infections, and injury to the urinary tract. In addition, they can also lead to complications with future pregnancies, such as causing the placenta to grow into the uterine muscle or too close to the cervix — sometimes blocking it — as well as rupturing the uterus.

While health care facilities in the U.S. are mostly prepared for these complications, that might not be the case in other countries, WHO noted. By putting only those who need them under the knife for C-sections, the money and resources needed to treat complications can be used for others' health care needs.

“These conclusions highlight the value of caesarean section in saving the lives of mothers and newborns,” said Dr. Marleen Temmerman, director of WHO’s Department of Reproductive Health and Research. “They also illustrate how important it is to ensure a caesarean section is provided to the women in need — and to not just focus on achieving any specific rate.”

Ghostly Galaxies Appear in the Coma Cluster

The word “galaxy” derives from the Greek for “milky,” but some such celestial systems look more like extremely skim milk. A new array of small telescopes has serendipitously discovered 47 “ultradiffuse” galaxies whose stars are so spread out from one another that they appear ghostly pale. Several of them are as large as our own, but each is much fainter, bearing roughly 1,000th as many stars as the Milky Way. No one knows how such odd galaxies originated.

The phantom galaxies materialized to astronomers after they deployed Dragonfly, an array in New Mexico composed of eight Canon telephoto lenses. “We just couldn't resist looking at Coma,” says Roberto Abraham, an astronomer at the University of Toronto, referring to a rich galaxy cluster in the constellation Coma Berenices. The cluster houses thousands of galaxies 340 million light-years from Earth and has a storied legacy: in the 1930s astronomers first detected dark matter there.

Dragonfly's Coma image did not disappoint. On it, Abraham and his colleagues saw faint smudges indicative of large, diffuse galaxies. By luck, the Hubble Space Telescope had captured one of them during an unrelated observation, providing more detail. The galaxies, it reveals, look nothing like our own. Instead they are smooth, round and devoid of any gas to form new stars, and although the objects resemble diffuse galaxies known as dwarf spheroidals, they are anything but small. The discovery is described in a January issue of the Astrophysical Journal Letters.

How did such bizarre and difficult-to-detect galaxies arise? Team member Pieter van Dokkum, an astronomer at Yale University, suspects the galaxies may be failed Milky Ways—big galaxies that were headed for brilliance but lost their gas before forming many stars, perhaps because supernova explosions catapulted gas out of the galaxies and into the parent Coma cluster. They also must harbor lots of dark matter to hold together; otherwise the gravitational pull of other galaxies in the cluster would rip them apart.

Exactly how much dark matter they possess is unknown because no one has yet achieved the feat of measuring their mass. Nevertheless, “they're great dark matter labs,” says Chris Impey, an astronomer at the University of Arizona. If dark matter emits radiation, these galaxies could be the place to see it.

This article was originally published with the title "Galactic Ghosts."

Conquer Phobias With Psychology Tool

It’s natural to feel uncomfortable around a spider, but for around 10 percent of the general population this discomfort disrupts quality of life. When that occurs, the fear becomes a phobia. Unfortunately for researchers, the extreme diversity of phobias makes them hard to study. But a doctoral candidate from Northern Illinois University may change all that with her unique new way to measure and assess fear, no matter the source. 

Kathleen McCraw is the mastermind behind the Circumscribed Fear Measure (CFM) — a first of its kind method of quantifying the severity of a wide range of specific phobias. More specifically, the CFM is a series of psychological assessments and questionnaires used to arrive at a specific “measurement” of a client’s fear, regardless of the type of phobia from which he suffers.

Typically, when a psychologist suspects a patient has a phobia, she will have the client conduct self-reporting assessments. McCraw explained in a press release that the problem with this is that measurements will differ greatly depending on the fear of the patient. This makes self-assessments ineffective for making comparisons between different phobias.

“For instance, if we want to assess fears of storms or water, both of which are relatively common fears, there are no self-report measures,” McCraw said.

Her measurement tool addresses this problem and allows for the measurement of a fear of any specific object or situation, allowing for the comparison of different phobias. For example, respondents identify their most feared object or situation and state how strongly they agree or disagree with statements like: “I avoid having to face this object or situation at all costs” or “When I am faced with that object or situation, I feel faint or dizzy.”

At the moment, the CFM is the only known tool capable of comparing different types of phobias, and its possible implications are vast

This measure will facilitate research studies that directly compare different types of phobias,” McCraw said. “Additionally, we think therapists will be able to use the CFM to track their clients’ progress throughout therapy.”

A phobia is an irrational fear that can cause great anxiety and suffering in those it afflicts. Fear is a survival mechanism, and our ability to fear danger keeps us alive. Unfortunately for some, the fear instinct goes above and beyond and can seriously interfere with their normal functions, Medical News Todayreported.

A particularly useful application for this tool is the study of phobias which run in families. Children with phobias often have fearful parents. The ability to compare the fears of children against the often different fears of their parents will help researchers to better understand and therefore better treat these conditions.

Vasalgel, Male Birth Control

Scientists have been working on a form of male birth control for years now, but it’s possible that we finally have a winner. Vasalgel, a non-hormonal polymer that blocks the sperm-shooting vas deferens in men, has shown promising results in a baboon study and could be available by 2017.

The Parsemus Foundation, a nonprofit organization that develops low-cost medical approaches, aims to start human trials for this contraceptive by next year. After finding that baboons injected with Vasalgel didn’t impregnate the 10 to 15 female baboons with which they shared the same space, scientists saw the possibility of the injection working in humans, too.

Vasalgel is non-hormonal and only requires a single shot to be effective for a long time. A polymer contraceptive is injected into the vas deferens, which transports sperm from the epididymis to the ejaculatory ducts. Unlike a vasectomy, which is permanent, Vasalgel could be reversed by flushing the polymer out with another injection, leaving sperm open, free, and available to do their job once more. If Vasalgel proves successfuly in human trials, couples in long-term relationships could enjoy sex without the hassle of condoms — and the adverse side effects and expenses of the female pill.

Revolutionizing' Birth Control?

If Vasalgel, or something like it, becomes widespread, then unwanted pregnancies — which occur at rates of 80 to 90 percent in women younger than age 19 — could also drop significantly. Females would no longer be under pressure to ask their partners to wear condoms or to take the pill themselves. Men, likewise, could find a quick and easy solution to having frequent sex without having to worry about babies.

So if this becomes a birth control revolution of sorts, everyone is happy, right? Probably not big pharmaceutical companies, who hope to maintain female birth control pill sales and will most likely put up a fight to keep their businesses afloat. These companies make their money off a pill that must be taken every day and thus replenished; this cycle keeps the cash coming in. As Samantha Allen writes on The Daily Beast, “Why sell a flat-screen television to a man, after all, when you can rent one to a woman for a decade?” A single injection contraceptive could create a barrier for female pill business.

One of the ways that current birth control pill companies might fight back is through advertising the other potential health benefits of pills, such as claiming they relieve period-related issues like cramps or headaches. In 2009, however, the Food and Drug Administration (FDA) cracked down on the popular pill Yaz, which advertised that it could also cure pimples or PMS symptoms, in addition to preventing pregnancy. But instead of helping other health issues, female birth control pills are more likely to cause adverse side effects, including headaches, dizziness, breast tenderness, nausea, bleeding, decreased libido, mood swings, and depression. In addition, birth control pills have been shown to slightly increase your risk of stroke, blood clots, high blood pressure, heart attacks, and liver tumors — especially among smokers. While this doesn't mean that female birth control users are damaging their health, it simply means that a potential male contraceptive could be safer than ever before — for both parties.

There is yet another thing to consider: Will Vasalgel also reduce condom use, and thus protection against sexually transmitted diseases? If a man gets a Vasalgel injection and stops using condoms for birth control, he might have a higher chance of getting or spreading STDs. But male birth control is still a few years away — and trials will first need to be completed in humans. So for now, condoms are probably your one-stop shop for protection against both pregnancy and STDs.

Viagra And Other Erectile Dysfunction Drugs Vary In Effectiveness, Side Effects

(Reuters Health) - Viagra is the most effective treatment for erectile dysfunction, but it also has a higher rate of side effects than other options, according to an analysis of more than 150 trials.

Viagra is known generically as sildenafil. Men concerned about possible side effects of Viagra like headaches, flushing, indigestion and nasal congestion may want to start on Cialis, which is known generically as tadalafil, researchers report in European Urology. If that’s not effective, men in some countries can try Zydena (udenafil).

Many men have trouble getting or keeping an erection, especially as they age, but erectile dysfunction – also known as ED - is not a natural part of aging, according to the U.S. National Institutes of Health.

The new review compares seven common ED therapies, all belonging to a class of medications called phosphodiesterase 5 inhibitors (PDE5i’s). They work by inhibiting an enzyme that may reduce the potency of an erection.

Viagra, Cialis, Levitra (vardenafil) and Stendra (avanafil) all work this way and are approved for use in the U.S. The additional drugs Zydena, Helleva (lodenafil) and Mvix (mirodenafil) are only approved for use in other countries.

PDE5i's are considered the first-choice therapy for ED, but they're only effective for 60 to 80 percent of men who try them, and many will stop taking them, according to Dr. Alexander W. Pastuszak of Baylor College of Medicine's urology department in Houston, Texas. He was not part of the new study.

Researchers at the University of Zurich, the Swiss Federal Institute of Technology, and Maastricht University Medical Center in the Netherlands reviewed 82 studies of the drugs’ effectiveness and 72 studies exploring side effects.

These treatments are all more effective than placebo for treating erectile dysfunction, and are generally safe and well tolerated, the authors note.

A 50- or 100-milligram (mg) dose of Viagra appeared to be the most effective treatment. It performed about 50 percent better than a placebo. Smaller doses were less effective. Stendra, in doses ranging from 50 to 200 mg, was among the least effective - only 20 to 30 percent more effective than a placebo.

The 50-milligram dose of Stendra was associated with the lowest rate of side effects of any medication - 8.5 percent of the time. A 20-mg dose of Levitra had the highest rate of side effects: 25 percent. Higher doses of Viagra and Cialis tended to cause side effects between 21 and 22 percent of the time.

“Viagra has an established efficacy and safety profile and remains an important treatment option for men with erectile dysfunction,” a spokesperson for Pfizer, makers of the drug, told Reuters Health in a statement. “Viagra has been studied for more than 15 years in more than 136 completed and ongoing clinical trials involving more than 23,000 men with ED.”

Side effects depend on which drug is used and what other enzymes the drug is able to inhibit, Pastuszak told Reuters Health by email. One of the main side effects of Viagra is visual changes, whereas Cialis more often causes muscle pain.

More generally, these types of ED drugs can cause a drop in blood pressure, because they are vasodilators, which open blood vessels, he said. He added that they should not be used with nitrate-based heart medications since they can cause a steep drop in blood pressure.

“Other common side effects include facial flushing, congestion, headache, and upset stomach,” Pastuszak said.

“Men complain of side effects, but more often of a lack of complete efficacy,” he said. “The drugs are not for everyone, as they won’t necessarily help a man with severe erectile dysfunction as much as they would someone with mild or moderate ED.”

Urologists will already have an understanding of the effectiveness and side effects of the available ED therapies, so the new results will not be a surprise, he said.

Only Cialis is to be taken daily, the other options are all short-acting, so men have the option of trying several to see which one works well, he said.

Doctors should carefully discuss expectations and treatment effects of the various options with patients before choosing a therapy, the authors write.

Some ED patients may want immediate stronger efficacy at the cost of higher side effects, while others may not.

What Causes Gray Hair

Saggy skin, (premature) wrinkles, and a stray or gray patch of hair are tell-tale signs of aging. A graying hairline is the most common sign related to chronological aging as the body begins to undergo visible changes. While the arrival of the silver mane is either celebrated or dreaded, we begin to wonder, what exactly causes our hair to turn gray as we age? Life Noggin’s YouTubevideo, “Why Your Hair Will Turn Gray,” sheds some light on the matter.

Similar to skin, hair texture changes as the body ages. Internal and external influences, especially genetics, help determine the exact moment our hair turns gray. For example, we tend to grow gray at the time either our parents or grandparents saw their first gray strand. Hormones, age, the climate we live in, toxins, and even chemical exposure can also affect hair pigmentation over the years.

Genetics is a strong indicator of why our hair turns gray, but how exactly does hair lose its pigmentation? The pigments of dark and light hair color are composed of melanocytes, which inject melanin into cells that contain keratin — the protein of our hair. Life Noggin suggests the defective maintenance of melanocyte stem cells means the less melatin is injected, the more gray our hair starts to produce.

Hair follicles grow separately and contain their own amount of melanin. This is why we see the occasional gray strand before we see a whole head of gray hair. However, stress or shock can actually speed along the graying process, but researchers are not quite sure why. A 2011 study published in the journal Cell was able to isolate the wnt protein, which coordinates pigmentation between stem cells that leads to the development of hair follicles and melanocytes. This can help scientists determine whether wnt interacts with chemical pathways induced by stress and whether the production of hair color is affected.

Gray hair is a normal and unavoidable part of aging that is usually not associated with disease. It’s perfectly normal and healthy to start going gray in your 20s. Typically, whites tend to gray in their mid-30s, followed by Asians and then Africans.

Serotonin

male mice will cheerfully mount both male and female mice, as long as their brains are deficient in one chemical messenger: serotonin. The paper, published in Nature, received plenty of media coverage. Now, two other research groups report seemingly opposite findings: Male mice with no serotonin in their brains still prefer female mice to males. The researchers contend that serotonin is about social communication and impulsive behaviors, not sex.

Mounting behavior aside, sexual preference in mice is not about “turning mice gay.” It never has been. Instead, it’s about the role that a single chemical can play in animal behavior. And it’s about what, exactly, those behaviors really mean.

Serotonin serves as a messenger between cells. It plays important roles in mood. Serotonin-related drugs are used to treat some forms of migraine. And of course, serotonin plays a role in the psychedelic effects of recreational drugs such ashallucinogens. So when the Peking University group set out to show serotonin’s role in sexual preference, they attacked it from several angles. They used mice that had been genetically engineered to lack the brain cells that usually produce serotonin. They used a chemical to deplete serotonin in the brains of normal mice. And they created another strain of mice that lacked the enzyme that makes serotonin in the brain.

In all three sets of animals, the researchers saw the same result. The male mice with no or low serotonin in their brains approached males and females with seemingly equal enthusiasm. Two years later, the Rao group doubled down. Using almost the same methods, they showed that female mice lacking serotonin in their brains will mount other females and will also accept male mounting, they reported in the Proceedings of the National Academy of Sciences.

This was not the creation of gay mice. Rather, for male mice deficient in serotonin, the sex of the other mouse simply no longer mattered. But is it really that simple? In a very general sense, increasing serotonin in the brain produces some of the side effects seen with serotonin-based antidepressants in humans, which include decreased libido and inhibited ejaculation. In contrast, drastic decreases in serotonin are associated in animals with increases in mounting. So is removing serotonin from the brain a deletion of sexual preference? An increase in libido? Something else? Serotonin has roles in many other behaviors and states, including aggression, feeding, impulse control and more.

Other scientists decided to find out for themselves. Mariana Angoa-Pérez, a molecular neurobiologist at Wayne State University School of Medicine in Detroit,  made her own version of the knockout mouse that the Rao group used, deleting or knocking out the enzyme that makes serotonin in the brain. But her male mice showed a marked preference for female urine and female mice, not the lack of sexual preference seen in the Rao group’s experiments.

 “Serotonin is related to hyper- or hyposexuality, but that’s different from sexual preference,” says Angoa-Pérez. “There are so many receptors and brain areas. It’s not a black-and-white issue.”

In particular, Angoa-Pérez and her collaborator Donald Kuhn, also at Wayne State, note that mounting behavior can be a sign of aggression and dominance between male mice. “Any behaviors we see related to sex are aggression-related,” Kuhn explains. He says that their experiments have shown that their low-serotonin mice are extremely impulsive and aggressive, “they just can’t control themselves.” They impulsively explore new environments, willingly try new foods (something normal mice are very shy about) and of course, willingly attack new cage mates. Kuhn and Angoa-Pérezpublished their findings on sexual behavior February 23 in PLOS ONE.

Now another study corroborates Angoa-Pérez and Kuhn’s findings. Daniel Beis and colleagues at the Max-Delbrück Center for Molecular Medicine in Berlin, bred their own version of the serotonin enzyme knockout mice. As in the other group’s study, the knockout males preferred female mice, and were hyperaggressive toward, well, everything. Beis concluded that decreasing serotonin in the brain produces deficits in social, not sexual, behavior. “I don’t like to say that serotonin is responsible for a single function, but that it’s modifying the system,” he says. “Stories cannot be so easily told as they sometimes are.”  Beis and his colleagues publishedtheir findings March 25 in Biology Letters. 

Rao, the lead author of the 2011 study, is fully confident in the results from his lab showing that brain serotonin regulates sexual preference. He says that the differences in the findings are probably the result of different experiment methods. “Three [of my] students have carried out these experiments before we were confident of the results,” he writes in an email. “Furthermore, the [Beis] paper did not use the standard methods used by us and others to perform the right experiments. Either they should have explained that our methods were wrong or they [should] repeat exactly what we did rather than doing experiments with different methods and analysis.”

The experimental results seem fairly contradictory. But it doesn’t necessarily mean that any one of those studies is wrong. “The data undoubtedly indicates the involvement of the brain serotonin system,” says Vladimir Naumenko, a behavioral geneticist at the Institute of Cytology and Genetics in Novosibirsk, Russia. But at the same time, he says, serotonin can be involved, without being the last word in sexual preference.

He also notes that differences in the methods used by the groups could play a role in the different experimental results. He explains that Beis looked at aggressive behavior, while Rao’s group did not. The Rao group used a mouse strain called C57Bl/6J, while the Beis group used a different one, C57Bl/6N, and the Kuhn group worked with a blended mouse, a mix of the C57Bl/6J mice and a strain called sv129. It may be a matter of just a few letters, but strains of mice can be strikingly different in behavior and have different levels of important brain chemicals. Finally, each group created their own knockout mouse to perform the studies. It is possible that different mouse strains — and knockouts — could result in dissimilar behaviors, from sniffing to mounting and everything in between. 

The studies raise the question of how, exactly, scientists should interpret mouse behavior, especially in the presence or absence of particular genes. Brain serotonin differences certainly could affect sexual behavior in mice. But it may not mean much, if anything, for humans. “I would say from a cultural perspective, results from animals are hardly transferable to such sophisticated things as human sexuality,” Beis says.

Mounting behavior in mice could have sexual intentions. It could have aggressive intentions. It could even mean something else. Time spent sniffing male or female could be a function of sex drive, or it could be the focused whiff of a less-sensitive nose. Odd behaviors could arise in mice that have never had serotonin, as their brains adapt to fill the gap. Many more mice will mount before scientists figure out exactly what role serotonin plays.

The seemingly inconsistent findings don’t mean that one scientist is wrong. As scientists continue to work on the sexy side of serotonin, they may discover new subtleties to mouse sexual behavior that change our knowledge of who mounts who and why. Wrestling over serotonin and sexual preference isn’t about “turning mice gay.” It’s about science working as it should — fumbling, somewhat gracelessly, toward understanding.

Are Paleo Diets More Natural Than GMOs?

In 1980 I subjected myself to a weeklong cleansing diet of water, cayenne pepper, lemon and honey, topped off with a 150-mile bicycle ride that left me puking on the side of the road. Neither this nor any of the other fad diets I tried in my bike-racing days to enhance performance seemed to work as well as the “see-food” diet one of my fellow cyclists was on: you see it, you eat it.

In its essence, the see-food diet was the first so-called Paleo diet, not today's popular fad, premised on the false idea that there is a single set of natural foods—and a correct ratio of them—that our Paleolithic ancestors ate. Anthropologists have documented a wide variety of foods consumed by traditional peoples, from the Masai diet of mostly meat, milk and blood to New Guineans' fare of yams, taro and sago. As for food ratios, according to a 2000 study entitled “Plant-Animal Subsistence Ratios and Macronutrient Energy Estimations in Worldwide Hunter-Gatherer Diets,” published in theAmerican Journal of Clinical Nutrition, the range for carbohydrates is 22 to 40 percent, for protein 19 to 56 percent, and for fat 23 to 58 percent.

And what constitutes “natural” anyway? Humans have been genetically modifying foods through selective breeding for more than 10,000 years. Were it not for these original genetically modified organisms—and today's more engineered GMOs designed for resistance to pathogens and herbicides and for better nutrient profiles—the planet could sustain only a tiny fraction of its current population. Golden rice, for example, was modified to enhance vitamin A levels, in part, to help Third World children with nutritional deficiencies that have caused millions to go blind. As for health and safety concerns, according to A Decade of EU-Funded GMO Research, a 2010 report published by the European Commission:

The main conclusion to be drawn from the efforts of more than 130 research projects, covering a period of more than 25 years of research, and involving more than 500 independent research groups, is that biotechnology, and in particular GMOs, are not per se more risky than e.g. conventional plant breeding technologies.

So why are so many people in a near moral panic over GMOs? One explanation may be found in University of California, Los Angeles, anthropologist Alan Fiske's four-factor relational model theory of how people and objects interact: (1) communal sharing (equality among people); (2) authority ranking (between superiors and subordinates); (3) equality matching (one-to-one exchange); and (4) market pricing (from barter to money). Our Paleolithic ancestors lived in egalitarian bands in which food was mostly shared equally among members (communal sharing). As these bands and tribes coalesced into chiefdoms and states, unequal distribution of food and other resources became common (authority ranking) until the system shifted to market pricing.

Violations of these relations help to show how GMOs have come to be treated more like moral categories than biological entities. Roommates, for example, are expected to eat only their own food or to replace one another's consumed items (equality matching), whereas spouses share without keeping tabs (communal sharing). If you invite friends to dinner, it would be disconcerting if they offered to pay for the meal, but if you dine at a restaurant, you are required to pay the bill and not summon the owner to your home for a comparable cuisine. All four relational models are grounded in our natural desire for fairness and reciprocity, and when there is a perceived violation, it creates a sense of injustice.

Given the importance of food for survival and flourishing, I suspect GMOs—especially in light of their association with large corporations such as Monsanto that operate on the market-pricing model—feel like an infringement of communal sharing and equality matching. Moreover, the elevation of “natural foods” to near-mythic status, coupled with the taboo many genetic-modification technologies are burdened with—remember when in vitro fertilization was considered unnatural?—makes GMOs feel like a desecration. It need not be so. GMOs are scientifically sound, nutritionally valuable and morally noble in helping humanity during a period of rising population. Until then, eat, drink and be merry.

Orange-Tinted Glasses Block Blue Light From Electronic Devices, Promoting Better Sleep

Staying connected 24/7 on our smartphones, tablets, and other electronic devices can make us well-informed readers but poor sleepers. Although we stay connected with the world from the privacy of our own home, these devices can intrude on the most intimate time we have to ourselves — sleep. However, according to a recent studypublished in The Journal of Adolescent Health, wearing a pair of orange-tinted glasses may effectively block blue light from light-emitting diode (LED) screens and prevent disturbing the sleep-wake cycle.

Our eyes have photoreceptors in the retina that sense light and dark, which signals our brain about the outside world and aligns our circadian rhythms. This signaling of light and dark helps us stay alert in the morning and fall asleep at night. This affects our circadian rhymes, which are the physical, mental, and behavioral changes that follow a 24-hour cycle that responds to the light and darkness of an environment, according to the National Institute of Health.

The blue light emitted from electronic devices has tampered with our circadian rhythm and our sleep cycles by blocking thesleep hormone melatonin. Typically, this hormone increases in the evening and helps induce sleepiness at night. However, these devices submit a sufficient amount of light to the brain, which interprets this as an indicator of wakefulness.

A team of Swiss researchers sought to investigate whether the use of blue light-blocking glasses (BB) during the evening, while sitting in front of a LED computer screen, can promote better sleep. A total of 13 healthy teenage boys between ages 15 and 17 were recruited for the study.

The boys were required to keep their regular sleep schedule at home but did not go out in the evenings or have caffeine drinks. The blue-blocker glasses were worn from 6 p.m. until bed time each evening, while the boys would log in how long they were the glasses an how much time they spent with LED and non-LED screens. They went through the weeklong study protocol twice, once wearing blue-blocker glasses and once wearing clear glasses.

Towards the end of the week, the participants spent one overnight in the lab, sitting for two hours in dim light, darkness for half an hour and then three hours in front of a backlit LED computer screen wearing the blue blocker glasses. The researchers conducted cognitive tests conducted and collected saliva samples. Following these tests, the boys went to sleep for eight hours, and then performed the same cognitive tests and gave their saliva samples similar to the night before.

The findings revealed when the boys wore their BBs, or orange-tinted glasses for a week, they reported feeling “significantly more sleepy” than when they wore clear glasses. The boys would look at their devices for a considerable amount of time before going to bed. Based on their saliva samples, those who wore clear glasses had less melatonin at bedtime compared to their counterparts who had higher melatonin levels up 90 minutes to five minutes before sleep.

“Blue blockers therefore can prevent those light responses which are not helpful in the evening hours when our body and mind has to prepare for sleep,” Vivien Bromundt, study coauthor of the Centre for Chronobiology at the Psychiatric Hospital of the University of Basel, told Reuters Health.

However, these orange glasses should not be seen as a cure-all for a good night’s sleep. Not all orange-tinted glasses are created equal nor have they all undergone the same testing to be a legitimate sleep aid. If orange-tinted glasses are not feasible, there are apps like the f.lu, which can change the bue light impact of electronic devices. Dr. Kevin Barrett, a licensed psychotherapist in Chicago, Ill., previously told Medical Daily: “…[b]efore reaching for supplements or medications, try putting away our phones two hours before bed. However, if this is not possible, Barrett recommends using the app F.lux (iPhone) or Bluelight Filter (Android), which reduce the blue light output of our screens.