Innholdsfortegnelse for October 2015 i Discover

A look at the research behind healthy-aging tips and advice. I spent several years as a health and medical writer, and published lots of advice columns in my time. You know the kind: packed with tips for losing weight, getting in shape, picking the right foods and so on, ad nauseam. Between you and me, those stories weren’t my favorite assignments. Plenty of readers found them lacking, too. They’d write in asking for more information. They didn’t want just distilled tips and plans. They were curious about the research behind the advice — how and why scientists came to conclusions that they did. And they didn’t want old news or advice based on research that was sometimes conducted years ago. They wanted to know what was in the works. What…

RISKY MEDICINE Our Quest to Cure Fear and Uncertainty By Robert Aronowitz Americans have the most advanced (and expensive) health care — but not the best health. Science and sociology historian Aronowitz suggests that our market-driven, risk management-focused health care culture has led to excessive tests and overdiagnosis. The cure? Reforming how we think about health and how it’s practiced. EUREKA How Invention Happens By Gavin Weightman Before (and after) the light bulb moment, when an idea becomes an innovation, there’s plenty of failure, doubt and competition. Historian Weightman covers the setbacks and the successes in five case studies, from the Wright brothers’ flying machine to the ubiquitous barcode. THE FOOD LAB Better Home Cooking Through Science By J. Kenji Lopez-Alt Whether you want to make a foolproof Hollandaise or…

An insatiable sweet tooth could lead to dementia. It’s possible. Diets high in fructose (fruit sugar) and sucrose (table sugar) can induce metabolic changes associated with Type 2 diabetes. And having diabetes later in life jacks up your risk of Alzheimer’s disease by 40 to 50 percent, according to a meta-analysis of studies in the 2014 World Alzheimer Report. How could a hard-core snacking habit damage your brain? As millions of cake and candy lovers can attest, frequent sugar binges tend to bring on weight gain. Fat cells grow larger when we gain weight, and the larger they get, the less sensitive they are to the hormone insulin, which cues the cells to take up glucose from the bloodstream. Decreased insulin sensitivity causes blood sugar levels to remain higher after…

Doctors call it presbycusis, but you’ve heard it called another name: agerelated hearing loss. Even though experts know the condition is primarily due to the loss of hair cells in the inner ear (among other factors), they remain no closer to figuring out how to prevent it. One reason is that it’s impossible to tell the difference between agerelated damage and damage due to prior noise exposure, says Frank Lin, associate professor of otolaryngology and epidemiology at Johns Hopkins University School of Medicine. “All we do know is that many cells within the inner ear are post-mitotic, which means once they’re destroyed, the body can’t regenerate them.” There are no proven pharmacologic therapies for age-related hearing loss, but that may soon change. One area researchers are looking into is symptomatic…

Aging research may be on the rise, but it does have its own set of unique limitations in terms of how quickly discoveries in the lab turn into human clinical trials. “There’s a lot of grumbling, both in the general public and the scientific community, about how often we cure diseases in mice that never translates when we try those cures in humans,” says Felipe Sierra, director of the Division of Aging Biology at the National Institute on Aging. Part of the problem, he says, is that the incidence of many human chronic diseases rises with age, yet many researchers prefer using young mice because of the pressures of being published and getting funding. Since most grants are usually only for a four- to five-year period, using younger mice is…

FROM THE LAB The more you do for others as you age, the more you do for yourself. Volunteering eases stress, which, in turn, lowers the risk of disease and mortality, particularly in those with cardiovascular disease. People older than 70 who volunteer for more than 100 hours a year report better health than senior non-volunteers, University of Minnesota researchers reported in 2005. Other studies show that committed volunteers have less chronic pain. Volunteering also gives participants a sense that they are valued and needed, which may ward off thoughts of being worn out or useless, says psychologist Benjamin Gottlieb of the University of Guelph in Ontario.…

Exercise is the fountain of youth. Maybe. While exercise is no panacea, it does confer plenty of benefits as we age. When Cardiff University epidemiologist Peter Elwood tracked the health outcomes of more than 1,600 people older than 45, he identified regular exercise as a key habit that reduced people’s risk of chronic conditions, such as diabetes and vascular disease in old age. “Exercise is one of the more important healthy behaviors and one of the things we can modify,” Elwood says. Regular exercisers enjoy a mental payoff as well as a physical one. Aerobic workouts not only stop brain shrinkage, but they also can help the hippocampus grow, according to University of Illinois research. And perhaps as a result, adults who routinely exercise are less likely to develop dementia,…

Your personality affects how well you age. Actually, yes. The grade-school Pollyanna who always turned in her homework may have had the right idea from a healthy-living standpoint. In a University of California, Riverside meta-analysis of 20 published studies, conscientious people were more likely to live longer, which makes sense: If you’re good at keeping promises and showing up on time, you’ll probably be good at sticking to healthy diet and lifestyle habits. An easygoing temperament may also confer a survival advantage. Studies of centenarians have found they’re more laid back than the general population and show more optimism about the future. On the other hand, people with pessimistic tendencies are more susceptible to conditions like high blood pressure and depression. But if you’re a worrier or a dyed-in-the-wool pessimist,…

Beer has just a few basic ingredients: water, hops, a grain and yeast. The artistry of beer-making comes in the specifics of the grain and yeast and/or bacteria used, and variations on production. Malted Grains It starts with malting, when the grain gets soaked in water to get it to sprout and produce kernels, or rootlets. This breaks down cell walls and creates granules. The grain gets heated in a kiln, which stops the germination process, and then it gets cleaned. Mill At that point, the malted grain is ground and goes into water for hydrating, a process known as mashing. Mashing activates enzymes in the grain that turn the starches into sugar, which you need for fermentation. The mash has to stay within a certain temperature range — it…

Finding hidden graves is often a hit-and-miss process that also can be dangerous in war zones and other areas of instability. Applying different remote sensing technologies could save time, focus resources and protect those searching for the dead. LIDAR Light detection and ranging technology (LIDAR) devices, on the ground or secured to a plane or helicopter, fire millions of laser pulses onto the landscape; some bounce off the forest canopy, some off the ground, creating a 3-D map that can reveal subtle changes in topography — including, potentially, graves that are otherwise invisible to the naked eye. Satellite Images Although satellites measuring vegetation provide limited data per square meter compared with LIDAR, their sensors can pick up areas with increased nitrogen uptake, a key chemical signature of a decomposing body.…

At Walvis Bay in Namibia, a scouring wind pushes sand dunes across an ancient mud flat. Sometimes when the dunes shift, the tracks of long-gone people and animals are exposed — much to the delight of Matthew Bennett, an ichnologist at Bournemouth University in England. Ichnologists study tracks and traces and other signs of living creatures, including the footprints left by our human and pre-human ancestors. As rare and prized as hominin bones in the fossil record, footprints evoke a different response. “A track is extremely emotive,” says Bennett. “If you see an ancient footprint, you are automatically drawn to it.” Indeed, at Walvis Bay the tracks emerge from the landscape as if they were just created. “One of the sites has [the tracks of] very small children in it,”…

Many experts believe an approximately 45,000-year-old bear femur could be a flute — the oldest known musical instrument. Ivan Turk discovered the bone in 1995 in Slovenia’s Divje Babe Archaeological Park, among cave deposits containing Neanderthal tools. But is it a hominin-made flute, or just a bone scavenged by ancient hyenas? In Science Smackdown, we let experts argue both sides of the question. A Bone Is Just a Bone Turk and his followers are wrong, says Cajus Diedrich, a paleozoologist and cave researcher in the Czech Republic. They didn’t properly consider the bone biting and crushing patterns of ice age hyenas that scavenged extensively in European cave bear dens. In a recent Royal Society Open Science paper, Diedrich argues that a hyena could’ve bitten holes in the juvenile cave bear…

For the past half-century, Thomas Lovejoy has studied “the shimmering variety of life on Earth” in the Amazon rainforest. The 74-year-old tropical biologist, who teaches at George Mason University, coined the term biological diversity in 1980 to refer to the millions of different species that comprise life on Earth, of which scientists have documented perhaps 10 percent. Unfortunately, countless organisms will vanish before we ever discover them, let alone investigate their potential benefits in fields like medicine, agriculture and genetics. But if we work now to restore ecosystems, Lovejoy argues, we can avoid the worst of these losses — and slow down climate change, too. Q Scientists say we face the largest mass extinction since the disappearance of the dinosaurs. You have pointed out that it isn’t just species that are…

For civilization, there’s no better time to understand aging. With roughly 10,000 baby boomers turning 65 in the U.S. every day, the “silver tsunami” is predicted to raise the national health care bill to $4 trillion in 2030. Globally, the 65-plus demographic is estimated to triple from 524 million in 2010 to about 1.5 billion by 2050. Most of us hope to live to a vigorous old age. And to help us do that, researchers are exploring ways to manage or overcome some of the most common and vexing age-related ailments. Here you’ll get a look at some of the most groundbreaking developments. But there are plenty of selfanointed health and nutrition gurus out there, too, spouting advice about diets, supplements and exercise to a population eager to try almost…

FROM THE LAB New evidence suggests that brain training, the cognitive equivalent of jumping jacks, can help keep your mind sharp into old age. Johns Hopkins researchers followed more than 2,800 adults age 65 and older who attended 10 onehour brain-training classes over the course of six weeks. Participants solved puzzles, memorized lists and did other mental exercises to hone their memory, reasoning and informationdigesting skills. Five to 10 years later, most subjects maintained gains they’d made and outperformed untrained control subjects, the researchers reported in 2014. So don’t let yourself become a mental couch potato. Keep up your cognitive fitness by tackling Sudoku puzzles or committing your grocery list to memory.…

FROM THE LAB You know it’s important to get the requisite eight hours (or at least seven) per night, but what’s more surprising is why it’s so important. People who have trouble sleeping are two to three times more likely to be depressed, a condition that weakens late-life physical defenses and accelerates mortality. When cognitive behavioral therapy, a form of talk therapy, was designed to instill better sleep habits — like waking up at the same time every day and confining sleep to bedtime only — it helped vanquish stubborn insomnia, according to data from an ongoing study at Toronto’s Ryerson University. Fully 87 percent of patients whose insomnia vanished saw their depressive symptoms improve as well.…

Can eating like a bird add years to your life? Don’t count on it. Since the mid-20th century, researchers have noted that calorie-restricted lab animals live longer than their well-fed counterparts. Naturally, some self-proclaimed health gurus have seized on these studies as evidence that humans could reap the same benefits by slashing their food intake. That prospect has inspired calorie-restricted diets that feature arcane ingredients like brewer’s yeast and psyllium husk and may total less than 1,200 calories per day. Despite these dieters’ herculean efforts — forgoing dessert in favor of processed whey protein is a pretty drastic move — there’s still no solid evidence that slashing calories will extend human lives. Rats do live about 40 percent longer on a calorierestricted regimen, and roundworms live up to 50 percent…

When it comes to your physique, it’s known that with age, hormone production changes, our bodies begin storing more fat, and you lose between 3 and 8 percent of lean tissue mass per decade starting at around age 30. “Many people that have maintained the same weight throughout their lives are not fully aware how their body composition has changed — until it unfortunately becomes unavoidably evident,” says Luigi Ferrucci, scientific director of the National Institute on Aging and former director of the Baltimore Longitudinal Study of Aging, America’s longest-running scientific study of human aging. Some of that process can be reversed through exercise and hormone therapy, but your bones are another matter. “You can only build your bone mineral density up until around age 25 to 30,” says Elizabeth…

FROM THE LAB Red wine contains substances that may delay aging. These include a plantproduced chemical called resveratrol, which spurs cells to increase production of sirtuins, the proteins that promote cell survival. A University of Connecticut study suggests that resveratrol helps stave off heart disease, and another study suggests that antioxidants like those found in red wine protect blood vessels from premature damage. But drinking too much worsens conditions like diabetes and high blood pressure, and may cause cancer and liver damage. National Institutes of Health experts advise that women consume no more than three drinks in a day and seven per week; men should not surpass four in a day and 14 per week.…

While many researchers are seeking new ways to combat age-related issues one at a time, some experts in the field of geroscience — the study of how aging causes disease — are uniting to develop preventive and therapeutic approaches to fight multiple diseases. “We’ve known that aging is a major risk factor for most chronic diseases for some time, but recently, we’ve gained a better understanding of the aging process’s basic underpinnings, which has allowed us to extend both life span and health — in animals at least,” says Felipe Sierra, director of the Division of Aging Biology at the National Institute on Aging. “There’s only so much we can gain in terms of disease-free longevity by curing individual diseases like cancer and Alzheimer’s one at a time, but if…

On the outskirts of Geneva, Switzerland, some 300 feet underground, is the biggest, most complicated machine ever built. With about 1,200 giant superconducting magnets, multiple-ton detectors, a worldwide computing grid and a staff of thousands, the Large Hadron Collider is an international undertaking beyond the means of any single nation. The project's mission: to see what happens when protons collide at 99.99999 percent of the speed of light in a 17-mile-long circular tunnel. The LHC started operating in 2008, yet for some physicists it only recently began to live up to its name. “I called it the Little Hadron Collider,” says Maria Spiropulu, an experimental physicist at the California Institute of Technology, “because during its first run, it only operated at half-energy.” That changed in April when the accelerator fired…

There’s no such thing as a “typical” medical marijuana patient. The marijuana clinics that I’ve visited have encompassed a wide swath of society, and the people I’ve met are living proof of the diversity of this population. Nevertheless, my first thought when I meet Rachel in this particular clinic waiting room is that she doesn’t belong here. Rachel is in her early 40s, blond and wearing a crisply tailored deep-blue suit that looks like it’s made of expensive silk. Just for comparison, the guy sitting next to her is a skinny, unshaven lad wearing baggy shorts, a tank top and flip-flops. He looks like he’s heading to the beach, while Rachel looks like she’s taking a well-earned break from a board meeting. Later I find out she’s the co-owner of…

Alan Turing has had a good run in recent decades. The great British mathematician, who died in 1954, was the focus of last year’s acclaimed biopic, The Imitation Game. The film, ostensibly based on Andrew Hodges’ 1983 biography Alan Turing, the Enigma, was only the latest in a string of plays, TV dramas and novels that told Turing’s story primarily through the lens of his wartime code-breaking activities at Bletchley Park and his struggles with his homosexuality. Popular reductions, however, tend to attribute every scientific development in a field to a single individual. When you read, “It is only a slight exaggeration to say that the British mathematician Alan Turing saved the Allies from the Nazis,” — to quote from the bookjacket copy and, one supposes, the mission statement of…

1 Charles Darwin was a big fan, particularly of the sundews, or Drosera. “It is a wonderful plant, or rather a most sagacious animal. I will stick up for Drosera to the day of my death,” he declared in a letter to botanist Asa Gray in 1863. 2 Sundews get their name from glistening, sticky, hairlike trichomes, which secrete enzymes that digest insects unlucky enough to get stuck. 3 The adaptation of trapping and digesting prey has arisen at least nine times in different plant families in response to soil lacking the nutrients nitrogen, phosphorus and potassium. 4 The 600 or so carnivorous species on the planet today thrive in places where other plants struggle, including bogs and heaths. 5 Fairly common Geranium viscosissimum is considered protocarnivorous: Its enzymes can…

PLACES OF THE HEART The Psychogeography of Everyday Life By Colin Ellard Despite the title, neuroscientist Ellard is decidedly unromantic about deconstructing both natural and human-made environments into components that trigger specific cognitive responses. From Neolithic monuments that awe to “playground casinos” that empty wallets, Ellard argues that a scientific understanding of how our surroundings affect us must be the foundation on which we build the cities and homes of tomorrow. A IS FOR ARSENIC The Poisons of Agatha Christie By Kathryn Harkup When it came to offing her characters, iconic crime novelist Christie preferred poison. Chemist Harkup delves deep into the history and science behind more than a dozen lethal substances, introducing each through its appearance in Christie’s writing. You don’t have to be familiar with the likes of…

Our solar system began as a swirling cloud of dust and gas, the remainders of exploded stars. In 1999, scientists launched a spacecraft called Stardust to take a better look. Stardust rocketed more than 3 billion miles around the solar system. Throughout the mission, particles of dust smacked into the spacecraft’s sample collectors, where they became lodged in an ultralightweight spongy material called aerogel. Seven years later, the probe returned to Earth, landing in Utah with its tiny precious cargo. Last year, scientists announced that seven of those teensy dust particles — stuck in the Space Age gel — seem to come straight from the solar system’s original embryonic cloud, based on initial analysis. They are likely interstellar dust particles: the ashy remains of ancient suns, stars that died fiery…

An active social life helps you live longer. True. Maintaining a strong social network may foster good health in part because support from sympathetic friends and family helps cushion the impact of life’s blows. When you lead a less anxious life, you’re less prone to certain chronic conditions, such as cardiovascular disease. George Vaillant, a psychiatrist who directed a study that has monitored a group of former Harvard students since 1939, writes, “It is social aptitude, not intellectual brilliance or parental social class, that leads to a well-adapted old age.” Barring a major drinking binge, being the life of the party is good for you. In fact, highly social people have a 50 percent better chance of survival than loners over a period of several years, according to Brigham Young…

From his work on the Baltimore Longitudinal Study on Aging (BLSA), Luigi Ferrucci has witnessed firsthand that, for everything we currently know, the process of aging remains as enigmatic as it is inevitable. And what knowledge we have gained over the years can sometimes be easily overturned. “For example, we used to believe people became grumpy as they got older. But an analysis of long-term data from the BLSA discovered that an adult’s personality generally doesn’t change much after age 30,” says Ferrucci. “In fact, people who are happy when they’re younger are likelier to be the same when they’re much older.” It turns out “grumpy old men” — or women, for that matter — may be gruff not because of age, but because they’re set in a personality shaped…

On a bright autumn day at the Viceroy Snowmass ski resort, Chad Yakobson, the 31-year-old owner of the Crooked Stave Artisan Beer Project, holds a goblet of a beer he makes called Surette. Like all of Crooked Stave’s styles, it’s made with Brettanomyces, or wild yeast, a category of beer that’s growing popular even as it fights a certain stigma of being overly bold. Brettanomyces, Latin for “British fungus,” appear on beer lists as wilds, funks and the term Yakobson likes the least, sours. The clear Rocky Mountain light pouring through the window in Snowmass Village, Colo., illuminates the goblet like a straw-colored bulb. “It’s grassy, citrusy and earthy,” Yakobson says to a gathering of two dozen people who have assembled for a seminar about Bretts. “The word people like…