TIME Research

Scientists Pinpoint Why Some People Are ‘SAD’ in Winter

"We believe that we have found the dial the brain turns when it has to adjust serotonin to the changing seasons"

Difficulty regulating a chemical in the brain may explain why some people suffer from season affective disorder (SAD), according to new research.

Scientists at the University of Copenhagen, who studied brain scans from more than 30 subjects, found that SAD patients had different levels of a neurotransmitter that regulates serotonin in their brains during winter and summer months, the BBC reports. Serotonin is thought to signal happiness in the brain, and, during the winter, the neurotransmitter that removes serotonin was present at higher levels.

“We believe that we have found the dial the brain turns when it has to adjust serotonin to the changing seasons,” lead researcher Brenda McMahon told the BBC.

The research confirms what other studies have suggested. “SERT fluctuations associated with SAD have been seen in previous studies,” European College of Neuropsychophar­macology professor Siegfried Kasper said. “But this is the first study to follow patients through summer and winter comparisons.”

[BBC]

TIME Research

4 Surprising Things Your Nose Can Tell You About Your Health

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Not being able to smell well could signal the early stages of Alzheimer’s disease

No one appreciates their sense of smell when they pass a trash heap or accidentally step in dog poop. But your nose knows a lot—not just when things stink. In fact, your ability to smell, or not, can tell you a lot about your health. Here’s why you shouldn’t take your whiffing powers for granted.

A bad sense of smell can signal an early death

Feel like your sense of smell has gone south over the years? If it’s less than stellar, it could be a tip-off that you’re not in good health. A new study from the University of Chicago Medical Center found that not being able to detect certain odors had an increased risk of dying within five years. A whopping 39% of older patients who couldn’t pick up on scents like orange, rose, and peppermint died within that time frame, compared to only 19% of so-so smellers, and 10% of good smellers.

HEALTH.COM: How to Live to 100

Poor smell detection may be a sign of Alzheimer’s

Not being able to smell well could signal the early stages of Alzheimer’s disease, according a Harvard Medical School study. Participants with elevated levels of amyloid plaques (telltale proteins found in the brains of Alzheimer’s patients) who performed worse on an odor identification test also had greater brain cell death. Why? When the disease starts to kill brain cells, this often includes cells crucial for your sense of smell.

HEALTH.COM: 25 Signs and Symptoms of Alzheimer’s Disease

Smelling something weird could predict a stroke

Some people pick up on more scents than others, but brief episodes of smelling something completely off-base—like fish when there isn’t any around—may be a sign of stroke or a seizure. The American Academy of Neurology says these “olfactory hallucinations” are usually unpleasant smells, but they can differ from person to person, according to the Mayo Clinic. Contact your doctor right away if your nose seems to be going haywire.

HEALTH.COM: 10 Stroke Symptoms Everyone Should Know

Imagining odors can precede a migraine

While it’s relatively uncommon, people may also hallucinate a smell as part of a pre-migraine aura, according to a review of research done by the Montefiore Headache Center. Again, the scents were mostly unpleasant: the most common were of things burning or decomposing.

HEALTH.COM: 18 Signs You’re Having a Migraine

This article originally appeared on Health.com

TIME Research

A Lot of Men Got Vasectomies During the Recession

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Up to an additional 150,000 to 180,000 per year between 2007 and 2009

The recession was accompanied by a sharp increase in the number of American men who underwent vasectomies, according to research presented Monday, though it’s unclear if economic woes actually led to more procedures.

Researchers from Weill Cornell Medical College looked at survey data from the National Survey for Family Growth, which interviewed more than 10,000 men between 2006 and 2010, according to the American Society for Reproductive Medicine. They wanted to get a sense of how the economic downturn from 2007 to 2009 affected men’s decisions about having kids.

Before the recession, 3.9% of men reported having a vasectomy, but 4.4% reported having one afterward, which the researchers calculated to mean an additional 150,000 to 180,000 vasectomies during each year of the recession.

The researchers also found after the recession that men were less likely to be employed full-time, and more likely to have lower incomes and be without health insurance. Nothing changed when it came to men’s desire to have children, but those who were interviewed after the recession were more likely to want fewer children.

It’s important to note that the study, which is being presented at the American Society for Reproductive Medicine’s 70th Annual Meeting, does not prove causation, meaning it’s unclear whether men were undergoing surgery for financial reasons. Though the researchers do conclude that their findings suggest Americans may be factoring economics into family planning—which is not necessarily a new trend.

TIME Diet/Nutrition

Here’s How to Stop Teens From Drinking Soda

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When kids learn how far they’d have to walk to burn off the calories in a soda, they tend to buy smaller sizes or stop buying it altogether, suggests a new study published in the American Journal of Public Health.

Researchers analyzed more than 3,000 drink purchases by children ages 7 to 18 at stores in low-income Baltimore neighborhoods and found that sugary drinks accounted for 98% of the beverages kids bought. But when researchers put up colorful signs with calorie information, that figure dropped to 89%. The most effective sign was the one that said it would take a five-mile walk to burn off the calories in the drink. Researchers argue that while laws already require beverage manufacturers to post caloric information, calorie numbers may not mean all that much to many consumers. More practical information, including statistics about how long it will take to burn calories, is easier to grasp.

“This is a very low-cost way to get children old enough to make their own purchases to drink fewer sugar-sweetened beverages, and they appear to be effective even after they are removed,” says study author Sara N. Bleich, an associate professor at Johns Hopkins University.

MORE: The Soda Industry’s Promises Mean Nothing

Sugar-sweetened beverages like sodas and energy drinks contribute significantly to a number of public health ailments that harm children, including obesity. In low-income communities the problem is especially rampant: Sugary drink consumption accounts for about 15% of a minority adolescent’s caloric intake, more than twice the recommended quantity. Interventions like this might help decrease that disparity.

“People don’t really understand what it means to say a typical soda has 250 calories,” says Bleich. “If you’re going to give people calorie information, there’s probably a better way to do it.”

Read next: The Soda Industry’s Promises Mean Nothing

TIME Aging

5 Reasons Why Women Live Longer Than Men

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Life expectancy in the U.S. is at an all-time high, according to a recent report by the Centers for Disease Control and Prevention (CDC). And while the news that we’re living, on average, to the ripe old age of 78 years and 9 ½ months isn’t that surprising, there is one stat that is: A girl born in 2012 can expect to live to 81.2 years—almost 5 years longer than a boy baby born the same year, who’s likely live to age 76.4. Weaker sex, indeed.

“Men are biologically and sociologically at a disadvantage from the time they’re conceived to the time they die,” says Marianne Legato, MD, professor emerita of clinical medicine at Columbia University College of Physicians and Surgeons and founder and director of the Foundation for Gender-Specific Medicine. Here’s why:

Females are tougher in utero

Two and a half as many boys are conceived as girls, Dr. Legato says, but they’re so much more likely to succumb to prenatal infection or other issues in the womb that by the time they’re born, the ratio is close to one to one. “They’re also slower to develop physically than girls prenatally, which means they’re more likely to die if they are preemies due to underdeveloped lung or brain development,” Dr. Legato explains.

HEALTH.COM: 10 Biggest Myths About the Flu

Women are less likely to be daredevils

Unintentional injuries are the third leading cause of death in men, according to the CDC; for women it’s only the sixth. Again, you can blame it on biology: The frontal lobes of the brain—which deal with responsibility and risk calculation—develop much more slowly in males than females, Dr. Legato says.

The result: Guys often take many more risks (which you probably already realize if your small son has taken one too many spins off his bike handlebars). “Almost inevitably, a male will take risks that a woman of his same age wouldn’t take,” Dr. Legato says.

Women succumb to heart disease later

Heart disease is the leading killer of both men and women, but men are more likely to develop it—and die from it—as early as their 30s and 40s. Women, on the other hand, typically develop heart disease 10 years later than men. They’re protected from it until menopause, since their bodies churn out estrogen, which helps keep arteries strong and flexible, says Dr. Legato.

HEALTH.COM: 15 Weird Things Linked to Heart Attacks

Women have stronger social networks

Friends make good medicine: People with strong social connections have a 50% lower chance of dying than those with few social ties, according to a 2010 study at Brigham Young University. “Most men tend to hold their stress and worries close to their chest, while women tend to reach out and talk to others,” Dr. Legato explains. The one exception: married men, which also explains why so many studies show that they’re likely to be healthier and live longer.

HEALTH.COM: How Friends Make You Healthier

Women take better care of their health

Men are 24% less likely than women to have visited a doctor within the past year and are 22% more likely to skip out on cholesterol testing, according to the Agency for Healthcare Research and Quality. In fact more than a quarter (28%) of men don’t have a regular physician and about one in five didn’t have health insurance in 2012, according to the Kaiser Family Foundation.

You can blame it on the so-called John Wayne syndrome: “Men often deny illness; they minimize symptoms because they don’t want to go to a doctor and find out something is wrong,” Dr. Legato notes.

HEALTH.COM: 10 Worst States for Women’s Health

This article originally appeared on Health.com

TIME Cancer

Can Low-T Therapy Promote Prostate Cancer?

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New rat research raises health questions for researcher

“Low T” therapy is a fast-growing trend for men who want to jack up testosterone—which declines naturally with age but which can also be clinically low in some people—and the testosterone therapy industry is predicted to reach $5 billion by 2017. The long-term safety effects of supplementing with the hormone is still in question, however—especially in light of a study earlier this year that found double the heart attack risk in certain men after starting testosterone treatments. Other research suggested there was no meaningful increase in heart risk, adding to the confusion. But a new rat study published in the journal Endocrinology raises some alarming questions about the increasingly popular drugs.

Maarten Bosland, PhD, study author and professor of pathology at the University of Illinois at Chicago’s College of Medicine, devised an animal model to test the tumor-promoting effects of testosterone in rats. He exposed a group of rats to a carcinogen, which would put them at risk of developing cancer. He also gave some of the rats testosterone, but no carcinogen. In a third group, he administered both the carcinogen and the testosterone. Then, he measured tumor growth among the two groups.

None of the rats developed prostate cancer when they were just exposed to the carcinogen, but 10-18% of them did when they were just given testosterone. When the rats were exposed to the carcinogen and then given testosterone—even at very low doses—50-71% developed prostate cancer. “I was totally amazed about how strong testosterone can work to promote the formation of prostate cancer in these animals,” he says.

Of course, an animal model can’t determine what will happen in men, but Bosland thinks a similar effect is possible. “Absent of having solid human studies, we won’t be able to say that—it’s just an extra warning signal,” he says. “But I think it’s a clear indication that there is risk.”

TIME Infectious Disease

Here Are The Diseases In NYC Rats

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A new reason to dodge the rodents

Infected with 1.6 bacterial agents and 3.1 viruses, the average New York City rat is a cesspool of disease. But perhaps more frightening to hear is that they’re also host to “many more novel viruses” with unknown potential to harm city dwellers, according to a new study in the journal mBio.

“Our findings indicate that urban rats are reservoirs for a vast diversity of microbes that may affect human health and indicate a need for increased surveillance and awareness of the disease risks associated with urban rodent infestation,” says the study, which looked at samples of blood, urine and feces in 133 rats.

The report found that about 40% of the rodents had at least one viral infection and nearly all had a bacterial infection. A total of 13 rats had more than five viruses. Salmonella and Bartonella were among the bacteria in the sample, but E. coli took the crown as the most common bacterial pathogen. Nearly 40% of rats in the sample had the bacteria, known to cause severe illness replete with vomiting and diarrhea. Pathogens associated with hepatitis C, which can cause liver failure, were among the most common viral pathogens present.

MORE: FDA Approves Combined Hepatitis Drugs

Diseases in rats can have implications for people who live in urban areas in close proximity to the rodents, which can often access the food supply. Despite the prevalence of rats in urban areas, the health implications of rat infestation has not been studied in great depth, but the study says that should change.

“With continued urbanization, highly successful synanthropic species like the Norway rat are likely to play increasingly important roles in zoonotic disease ecology as the size and complexity of the human-rodent interface increases,” the study reads.

To translate, as humans and rats cross paths more often, the potential to pass along disease will increase.

TIME Research

Those Pesky House Flies May Actually Improve Our Health

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According to new research in 'Genome Biology'

The house fly is a rarely celebrated insect, but new research published Tuesday finally provides the pest with some positive recognition.

The house fly (Musca domestica) has a genome that could actually give scientists insight into pathogen immunity, helping humans live healthier lives, researchers write in the journal Genome Biology. And it’s all because of their, well, gross-factor. Since the house fly lives on animal and human waste, according to Science Daily, “[t]hey are an important species for scientific study because of their roles as waste decomposers and as carriers of over 100 human diseases, including typhoid, tuberculosis and worms.”

Their immunity system genes can be studied to help humans be healthier in toxic and disease causing environments, the researchers add, and detoxification genes could help scientists find better ways to manage toxic environments.

TIME Research

Ann Romney Launches Center, Says Family ‘Done’ With Campaigning

“Not only Mitt and I are done, but the kids are done. Done. Done. Done”

As the political world speculates about a potential third Mitt Romney bid for president, Ann Romney has other things on her mind. On Tuesday, she launched a center at the Brigham and Women’s Hospital in Boston aimed at solving some of the world’s most devastating neurological diseases.

Ann Romney also laid to rest any rumors that her husband might run again, the Los Angeles Times reported. “Not only Mitt and I are done, but the kids are done. Done. Done. Done,” she said.

“By combining Brigham and Women’s Hospital’s unique assets with the world’s most advanced resources and minds, the center will accelerate life-giving breakthroughs,” the hospital’s president Betsy Nabel said in a press release.

Ann Romney said her personal experience with multiple sclerosis (MS) and the work of the doctors at Brigham and Women’s inspired the center.

“I know firsthand how terrifying and devastating these neurologic diseases can be, and I want to do everything in my power to help change outcomes for future generations,” she said in a press release. “The team at Brigham and Women’s Hospital gave me the gift of enduring hope and that is what this center is about.”

The center, planned to open in 2016, will focus on preventing and curing MS, Alzheimer’s disease, Parkinson’s disease, brain tumors and Lou Gehrig’s disease.

Read next: The Pros and Cons of ‘President Grandma’

TIME Research

Stem-Cell Researchers Make Breakthrough in Type 1 Diabetes Treatment

"We are now just one pre-clinical step away from the finish line"

Updated Oct. 13

Researchers have made a major breakthrough in finding a treatment for type 1 diabetes, Harvard University announced Thursday.

For the first time, scientists were able to create insulin-producing beta cells using human embryonic stem cells, at a volume required for cell transplantation and pharmaceutical use. Type 1 is the variety of the metabolic disease that can be inherited and which is likely due to an underlying autoimmune condition in which the body destroys the beta cells that produce insulin, a hormone that regulates glucose and helps the body process sugar. (Unlike type-2 diabetes, there is no way to prevent type-1.)

“We are now just one pre-clinical step away from the finish line,” said Doug Melton, who led the research and who has worked toward finding a cure for diabetes since his son was diagnosed as an infant 23 years ago.

That final step is finding a way to protect the 150 million beta cells needed to for transplant in the treatment of each patient from their immune systems, which automatically attack those cells. Melton is working with other researchers to develop a device for such protection. Tests of a device in mice have so far protected insulin-producing beta cells for several months.

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