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Behind nearly every piece of science news you read is a magic number: the p-value.

Rethinking Science’s Magic Number

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 When a new scientific finding arrives in your newsfeed, it is often too early to recognize whether it’s undercooked. Consider “power posing,” the focus of
 <a href="http://datacolada.org/wp-content/uploads/2015/05/Carney-Cuddy-Yap-2010.pdf">
 a Harvard Business School study
 </a>
 . By standing like a superhero one minute a day, its authors found that it boosted testosterone, reduced stress hormones, and generally made people feel empowered.


 Not long after, a “power pose”
 <a href="https://www.ted.com/talks/amy_cuddy_your_body_language_shapes_who_you_are">
 TED talk
 </a>
 went viral, leaving a trail of anecdotal success stories and garnering millions of views.
 <a href="http://www.businessinsider.com/power-poses-interview-body-language-2014-3">
 Business
 </a>
<a href="https://www.inc.com/magazine/201205/leigh-buchanan/strike-a-pose.html">
 websites
 </a>
 were quick to promote the “power pose” life hack—it was backed by science, after all.


 And then it all came crumbling down. A nearly identical experiment, using more thorough methods and four times as many study participants,
 <a href="http://datacolada.org/wp-content/uploads/2015/05/5110-Ranehill-Dreber-Johannesson-Leiberg-Sul-Weber-PS-2015-Assessing-the-robustness-of-power-posing-no-effect-on-hormones-and-risk-rolerance-in-a-large-sample-of-men-and-women.pdf">
 did not find evidence
 </a>
 that power posing did any of those things.
 <a href="http://journals.sagepub.com/doi/abs/10.1177/1948550616652209">
 An offshoot study
 </a>
 further failed to reproduce the magic of the “power pose.”


 It’s easy to feel hoodwinked, but at the time of its release, author
 <a href="https://www.nytimes.com/2017/10/18/magazine/when-the-revolution-came-for-amy-cuddy.html">
 Amy Cuddy
 </a>
 genuinely believed her research findings. In fact, her statistics seemed to back her up, and peer reviewers had given her the thumbs up. And she is not alone—for decades, scientists and the media alike have consumed claims from single-publications as fact. As meticulous as scientists are, inaccurate, false, or even misleading science claims are surprisingly common.
 <a href="http://science.sciencemag.org/content/349/6251/aac4716">
 A 2015 experiment
 </a>
 reported over one-third of psychology experiments are faulty, while a similar test for
 <a href="https://elifesciences.org/articles/23693">
 cancer research
 </a>
 indicates similar trends, though that one is still in progress. The problem isn’t limited to those two fields, either.

<h2>
 Magic Number
</h2>

 Behind nearly every piece of science news you read is a magic number: the p-value. To generate a p-value, scientists run statistical tests comparing data sets. Their starting assumption is that there’s no difference between the things they’re comparing—new drug vs. sugar pill, power pose vs. nothing—and when they find a result that deviates significantly enough from “no difference,” they report it as a positive finding.


 “If you assume that nothing is going on…and get a surprising set of data, it might make you wonder whether there is something going on.” said Daniel Lakens, an assistant professor of applied cognitive psychology at Einthoven University of Technology in the Netherlands.


 You can think of the p-value as a “warmer-colder” game for scientific knowledge: a low p-value shouts “warmer,” while a high p-value reads “colder, not much to see here.” It’s a helpful tool, but it’s not perfect. And the threshold that most scientists use is less perfect than some would like.


 The p-value was originally devised by French scholar Pierre-Simon Laplace, a contemporary of Napoleon Bonaparte. Sir Ronald A. Fisher later popularized it after a famous experiment involving a lady who could taste differences in virtually identical cups of tea. Fisher proposed a p-value threshold of 0.05, and his ideas laid the groundwork for modern experimentation as it exists today.

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 Over time, p = 0.05 has morphed into a Caesar’s thumb for research.

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 “For decades, the conventional p-value threshold has been 0.05,” says Dr. Paul Wakim, chief of the biostatistics and clinical epidemiology service at the National Institutes of Health Clinical Center, “but it is extremely important to understand that this 0.05, there’s nothing rigorous about it. It wasn’t derived from statisticians who got together, calculated the best threshold, and then found that it is 0.05. No, it’s Ronald Fisher, who basically said, ‘Let’s use 0.05,’ and he admitted that it was arbitrary.”


 But over time, p = 0.05 has morphed into a Caesar’s thumb for research, making it hard to publish anything that doesn’t fall under that threshold. What’s worse, the pressure to report a passing p-value leads some scientists to resort to
 <a href="https://www.nature.com/news/collateral-damage-how-one-misconduct-case-brought-a-biology-institute-to-its-knees-1.17427">
 misconduct
 </a>
 .


 One form of misconduct, called “p-hacking,” occurs when scientists selectively embellish a few, randomly extreme data points, and conceal many insignificant ones. Their work passes the p-value threshold and makes the effects of their experiment seem more convincing than what occurs in reality.


 The NIH Clinical Center has reined in p-hacking in federally funded projects through improved the surveillance. By registering on websites like
 <a href="https://www.clinicaltrials.gov/">
 www.clinicaltrials.gov
 </a>
 , researchers are required to outline their experiments upfront. Scientists must then report their results in that same registry. Since the information is tracked, non-significant results get regularly communicated, making it more difficult to p-hack.


 Most fields don’t have a registry and instead rely heavily on publications for peer-review of research, which has its shortcomings as well. Peer-review can work well, but it only analyzes experiments after p-values have been produced, for example.

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<h2>
 A Warning
</h2>

 Misconduct or not, many statisticians and scientists are concerned about the improper use of p-values. The American Statistical Association recently issued
 <a href="https://amstat.tandfonline.com/doi/abs/10.1080/00031305.2016.1154108#.WpB1D62ZP-a">
 a stern warning
 </a>
 against misuse of p-values, a first in its 179-year existence. “The p-value was never intended to be a substitute for scientific reasoning,” its director wrote.


 That said, there may be one easy fix—lowering the p-value for significance. When examining the p-values of psychology claims that successfully passed the
 <a href="http://science.sciencemag.org/content/349/6251/aac4716.full?ijkey=1xgFoCnpLswpk&amp;keytype=ref&amp;siteid=sci">
 reproducibility test
 </a>
 , Open Science Collaboration authors noted that studies with the lowest p-values were more likely to pass, suggesting that low p-values could help weed out intentionally and unintentionally spurious claims.



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 “The p-value was never intended to be a substitute for scientific reasoning.”

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 Some research fields have voluntarily opted for more stringent p-values, because p = 0.05 was not strict enough. Particle physics, for example, has replaced the conventional p = 0.05 with “five sigma” or, p = 0.0000003, allowing them to announce discoveries, like the
 <a href="https://home.cern/topics/higgs-boson">
 Higgs boson
 </a>
 , with extraordinary confidence. Genetics applies similar thresholds to help scientists focus on the most relevant genes among the thousands residing in our genomes.


 Another branch of statistics also supports lowering the p-value threshold. Valen Johnson of Texas A&amp;M University analyzed scientific claims made with p-values of 0.05 using what’s known as a Bayesian approach. Most results were inconclusive. It wasn’t until the p-value neared
 <a href="http://www.pnas.org/content/110/48/19313">
 0.005
 </a>
 that the research claims satisfied both varieties of stats—and in Johnson’s eyes, were scientifically believable.


 Last summer, a similar, albeit less-technical
 <a href="https://www.nature.com/articles/s41562-017-0189-z">
 publication
 </a>
 emerged in the renowned journal
 
 Nature
 
 , where 72 prominent scientists reiterated Johnson’s sweeping proposal. Unsurprisingly, Johnson was among the lead authors.


 Think of the p-value as a filter: with a high p-value, the holes in the filter are wider, and some plausible-sounding data that was actually just randomness will make it through the peer-review process. However, if you reduce the p-value to 0.005, the filter becomes much more stringent.


 That sounds great, but Dr. Wakim argues that the proposed solution creates a new problem for clinical research: filtering out real discoveries that could translate into treatments—and potentially lives saved. He’d rather see a false-positive discovery be neatly corrected later, rather than miss it altogether.

<h2>
 Alternative Approaches
</h2>

 The breadth of the p = 0.005 proposal stepped on many researchers’ toes, and it wasn’t long before the internet blew up in response. Lakens seized the wave of attention to organize
 <a href="https://docs.google.com/document/d/12CNMlmxhD2q6mymyDl_Bp1mTIAAiWCblZneDDQc2nQY/edit">
 a Google Doc
 </a>
 , hosting a massive (and surprisingly organized) open-dialogue on the subject. Scientists with diverse backgrounds and experience levels contemplated how a standard of p = 0.005 would be implemented.


 Ultimately they did not agree with the 72-author publication—there was too much uncertainty on how potential benefits could justify costs.

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 If a specific experiment is repeated, and the outcomes are the same as before, we can feel more confident in the results.

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 Instead, the Google Doc’s authors entertained less rigid alternatives. One proposal was that each field or community might set its own threshold of significance. This is because the costs and benefits of changing a p-value vary depending on the discipline.


 Lakens likens the conflict to a debate over speed limits. “It’s like saying we have a lot of accidents when we drive, and we could fix it if we set the driving speed to 20 miles per hour because then we’re never going to have lethal accidents,” he says. “But then of course you don’t get anywhere as quickly anymore. And maybe you cannot make some trips because they are too far. It’s sort-of the same for science, so you can make it very slow, and careful…but whether it’s actually optimal in the complete sense of weighing all the costs and benefits, it’s not very clear.”

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 Lakens would rather see more studies that attempt to reproduce previous experiments. After all, if a specific experiment is repeated, and the outcomes are the same as before, we can feel more confident in the results. And with scientists knowing their work could be challenged with replications, they might feel less inclined to p-hack.


 But repeating an experiment is currently less dazzling than publishing a new finding, and it’s expensive. A few grants exist to address the latter issue, but the former is more intractable. New results are almost always better received than confirmations of what we already thought we knew.


 Dr. Wakim would like to see scientific journals accept results no matter the p-value. “Scientific discoveries take a long time, and many of them happen by elimination of unlikely explanations,” he says. Negative results, while not as exciting, have real value.


 Similar to Thomas Edison’s discovery of 999 ways not to make a lightbulb, negative results inform future research efforts, making science more efficient. What’s more, if scientists are transparent about their p-values, organizations like the
 <a href="http://www.cochrane.org/">
 Cochrane Collaboration
 </a>
 readily use this data for meta-analyses. Detecting a cohort of similar claims, all with p-values slightly above 0.05, results in a form of significance all its own that stand-alone studies could not necessarily substantiate.


 “People say, ‘Ugh, it’s above 0.05, I wasted my time.’ No, you didn’t waste your time.” says Dr. Wakim. “If the research question is important, the result is important. Whatever it is.”


 Photo credit:
 <a href="https://www.flickr.com/photos/dvanzuijlekom/9223220544/">
 Dennis van Zuijlekom / Flickr (CC BY-SA 2.0)
 </a>

For generations, scientists have relied on one number to determine the value of their research. Now, some are considering alternatives.

With people living longer than ever, can science give us a means to defy age, and keep our neurons and dendrites in good shape?

Single Gene May Dramatically Reverse Age-Related Mental Decline

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 Our brains are marvelous memory machines. Repeated use of a specific brain circuit—reminiscing about your favorite pet, solving puzzles, or practicing the violin—encourages new circuits to stay with us for life. When we neglect to engage them, our circuits—and encoded memories—can wither into oblivion (reinforcing the old adage, “use it or lose it”).


 And yet, even when we take strides to keep our minds sharp, we don’t always have a say in the matter. As we age, our mental capacity to learn and retain information is
 <a href="https://www.cdc.gov/mmwr/pdf/wk/mm6218.pdf">
 at risk
 </a>
 to deteriorate rapidly with age.


<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4015335/pdf/nihms569964.pdf">
 Age-related mental decline
 </a>
 doesn’t interfere with a person’s daily life to the extent of dementia, but it does compromise social interactions and can turn once-trivial mental tasks into unexpected bouts of frustration.


 With people living longer than ever, can science give us a means to defy age, and keep our minds intact?


 To do this, we need to understand our brains and how age augments them. In extreme cases, such as Alzheimer’s, cell by-products physically accumulate and clog neural pathways, creating a blockade in normal circuits. However, normal brain-aging changes are much more nuanced—several years ago, Phillip Landfield and his group of researchers at the University of Kentucky noticed old brain cells retain unusually high levels of calcium—one of several key ions in brain circuits.


 Taking a closer look, the scientists discovered a coinciding deficiency: a protein called FPBP1b was drastically low when compared with youthful brains.


 Attempting to reverse these age-related deficits,
 <a href="http://www.jneurosci.org/content/early/2017/12/18/JNEUROSCI.2234-17.2017">
 Landfield
 </a>
 and his group injected elderly mice with a virus engineered for cranking-up FKBP1b protein levels in their brains. These mice were then challenged with a memory-intensive exercise: navigating a water maze and learning where a hidden platform exists.

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 Much to their surprise, the mice not only outperformed their age-matched counterparts, but their neurons had drastically reverted back to more youthful characteristics. Examining the brain cells at a molecular level, some 800 genes unexpectedly began reverting back to “young brain” levels. With so many punctuated changes arising from a single protein, FKBP1b (and calcium levels it controls) is much more relevant to mental aging than previously thought.


 Many of the augmented genes were tied to important brain cells activities, such as rewiring connections and transmitting electrical signals. However, inflammation signatures were unchanged throughout the regenerative process, prompting scientists to pause and question how much inflammation impacts aging (currently a hot topic in the realm of brain research).


 Obviously, much more work is required to develop a medicinal equivalent to the “fountain of youth,” but this study is an encouraging first-step. It opens the door for understanding how certain key proteins, such as FKBP1b, keep our minds sharp as we venture into retirement.

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 Photo credit: Public Domain

With people living longer than ever, can science give us a means to defy age, and keep our minds intact?

Can You Change Your Microbiome?

“I can’t believe it—he’s a chatterbox!” Samantha Jones* shrieked with delight.


 Her autistic son was typically quiet, nearly non-verbal most of his life, but
 <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5264285/">
 a microbiome-augmenting treatment
 </a>
 had drastically improved the child’s behavior—like the flip of a light switch. Jones’s child was part of a study that examined the role that microscopic critters living inside us, collectively known as the microbiome, can play in gastrointestinal issues and autism. While the study was small, it suggests that altering our microbes can have wide-reaching consequences—sometimes for the better.

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 Our microbiomes dictate more about our bodies and our lives than we may like to admit. The influences range from the obvious, such as intestinal health, to the surprising, such as our moods. When microbiome-augmentation coincided with Jones’s child going from nearly non-verbal to conversational, it hinted at the astounding authority microbes can wield over human wellness.


 The science is anything but settled, though. After years of connecting the dots between microbes and human health, scientists have begun using microbes for medicine—but is it precise enough, and at what cost? And can we use that knowledge to alter our own microbiomes for the better, even if we aren’t sick?



 It wasn’t up until the late 1990s that microbial ecologists turned their attention to people and unearthed a microbial symphony within.
 


 Research efforts accelerated in 2008 when technology developed by the Human Genome Project made it easier to identify microbes by rapidly sequencing their genetic material. The diversity those tests revealed was startling: Scientists now estimate that roughly 1,000 distinct microbe species have evolved specifically for living in the human body, and a healthy person’s microbiome contains combinations of hundreds of different species—making your microbiome unique like your fingerprint.


 Links between microbial diversity and human health have been multiplying. Animal studies have helped scientists understand how the microbiome may influence a vast array of diseases, including irritable bowel syndrome, anxiety, immunity, schizophrenia, obesity, and more. Scientists were amazed when transplanting microbes between social and hermit-like mice led to
 <a href="https://www.gastrojournal.org/article/S0016-5085(11)00607-X/pdf">
 personality swaps
 </a>
 . A similar study found that transplanting microbes from an obese human to a mouse resulted in the mouse
 <a href="http://science.sciencemag.org/content/341/6150/1241214">
 gaining weight
 </a>
 . From nearly every health angle, the long-overlooked microbiome seemed to play a role.


 Studying microbes in humans, however, has been challenging. Since each person’s microbiome is unique—even if two people have similar lifestyles and health histories—it’s difficult to make broad comparisons.



 Still, a general trend has stood out—healthy people harbor more diversity in their guts.
 


 That would seem to suggest that adding “good” microbes to our bodies via probiotics would lead to major health benefits. In theory, this could be as simple as eating yogurt or swallowing a pill.


 Unfortunately, consuming microbes doesn’t necessarily mean they’ll reach your intestines alive. The human body is designed to annihilate microbial intruders—germs and probiotics alike. When you eat probiotic “live culture” yogurt, for example, stomach acid digests most microbes along with the food.

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<img alt="" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/shigella_LTHM97v.width-990_dfj5c1P.jpg"/>
<figcaption>
</figcaption>
</figure>

 To make matters worse, microbes suited to live in your intestines need
 <a href="https://insights.ovid.com/pubmed?pmid=22955366">
 accommodations
 </a>
 to survive from the factory to your mouth. Dr. Geraint Rogers, director of microbiome research at South Australia Medical Research Institute, says it’s hard to tell whether over-the-counter supplements provide accommodations that work. “Charlatans can pick some bug off shelf that already has FDA approval, stuff it into pills, and cite the science for health benefits, but these are anaerobes—they can’t survive with oxygen. If you analyze the pills, most have nothing in them that’s viable,” Dr. Rogers says.


 Even the probiotics that manage to reach your intestines don’t do much for long. Microbiologists speculate that our microbiomes don’t necessarily have vacancies for new members. By default, most probiotics that reach your intestines behave like tourists—they stay a little while before moving on to the next destination (in their case, the toilet).



 So how is it that, despite these long odds, some probiotic foods still appear to offer health benefits?
 


 A research group in Madrid, Spain sought to answer that question while
 <a href="https://academic.oup.com/ajcn/article/87/1/91/4633219">
 studying the link between probiotic yogurt and mental health.
 </a>
 After participants dieted on either live culture yogurt, dead culture yogurt, or no-culture yogurt, they were scored for mental health (responses to sadness, rumination of sad thoughts, and feelings of anger or frustration). Regardless of whether probiotics were dead or alive, scores improved when participants dined on culture yogurts. Yogurts lacking microbes, however, conferred zero benefits, so what changed?


 One explanation is that culture foods contain prebiotics—compounds that act like fertilizer good microbes inside you and food to fuel their beneficial activities. Oftentimes, microbes take food your intestines haven’t absorbed and convert it into something useful.
 <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3735932/pdf/2325.pdf">
 Dietary fiber
 </a>
 , for example, is good for your gut because microbes break it into smaller compounds that nourish and energize your intestinal lining. The byproducts from feeding microbes dietary fiber also seem to reduce
 <a href="http://science.sciencemag.org/content/359/6380/1151.long">
 type 2 diabetes risks
 </a>
 and
 <a href="https://onlinelibrary.wiley.com/doi/abs/10.1002/eji.201747122">
 inflammation
 </a>
 . Snippets of protein can be converted into an array of
 <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5408485/">
 neurotransmitters
 </a>
 —chemicals that directly influence our brains and nervous systems—and these byproducts appear to improve people’s moods. Gut microbes also use leftovers to make compounds that
 <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5787545/pdf/fimmu-09-00005.pdf">
 stabilize
 </a>
 your immune system and can neutralize carcinogens from red meat.



 One option for enhancing your health via the microbiome is adjusting your diet.
 


 Somewhat anticlimactically, this translates into a dietary strategy that’s old news: eat less fat, more vegetables, and more fruit. However, this can be challenging for creatures of habit; for decades we’ve been instructed to eat more fruit, more vegetables, and less fat to prevent obesity—yet the
 <a href="http://www.who.int/en/news-room/fact-sheets/detail/obesity-and-overweight">
 WHO
 </a>
 reports that obesity has tripled around the world between 1975 and 2016. Given that dismal trend, Dr. Rogers thinks it’s unlikely people would change their dietary habits for their microbiome.


 Which is why microbiome researchers have devised a dietary loophole: prebiotics in pill form. Consider red meat: In spite of increasing colon cancer risks, most people are reluctant to write-off the staple of Western diets altogether. There may be a way to counteract our irrational choices, though. A recent
 <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4531472/">
 clinical trial
 </a>
 demonstrated that consuming a pill stuffed with a corn derivative fueled microbe activity that returned carcinogens back to a healthier baseline.

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 There are also instances where an unhealthy microbiome isn’t the result of questionable choices but bad luck.
 


 Consider a cancer patient whose microbiome was completely
 <a href="http://www.drperlmutter.com/wp-content/uploads/2015/09/Montassier_et_al-2015-Alimentary_Pharmacology__Therapeutics.pdf">
 ablated from chemotherapy
 </a>
 or an
 <a href="http://science.sciencemag.org/content/350/6265/1214.full">
 elderly
 </a>
 person whose microbiome is inexplicably dwindling with age or an infant born deficient in microbes.


 For some desperately ill adults, this is often where fecal transplants come into play, where microbes from a healthy donor are transplanted into a sick patient. Unlike probiotic supplements, fecal transplants are classified as a medical treatment, and doctors can be sure the transplanted microbes reach the intestines alive. Dr. Monika Fischer from Indiana University is one doctor who uses fecal transplants to treat her patients. She administers the bright blue capsules, lovingly called “poop pills,” to patients suffering from
 
 C. difficile
 
 infections. Fischer cites research approximating “33 billion colony forming units” being enough to “repoopulate” the recipient’s intestines. Strength in numbers—and the fact that the pills are kept frozen under exacting conditions—may be why fecal transplants work where other probiotic treatments fail. Follow-up studies have confirmed a subset of transplanted probiotics have persisted up to
 <a href="https://www.nature.com/articles/s41522-017-0020-7">
 one year
 </a>
 after treatment.


 However, Dr. Fischer acknowledges that beyond
 
 C. difficile
 
 infections, one-time fecal transplants often aren’t enough for a microbiome reset. Irritable bowel syndrome patients, for example, don’t retain probiotics long-term, and must take the pills every other day to sustain health benefits. Dr. Fischer attributes the difference to divergent intestinal landscapes. “A
 
 C. difficile
 
 patient is a very unique case scenario, having a very diminished microbiome…Normally you have a healthy ‘forest’ in the gut. After
 
 C. difficile
 
 , the forest looks like a war zone—there are very few trees left.” Dr. Fischer says.


 Though
 
 C. difficile
 
 infections may be unusually responsive to fecal transplants, the approach has inspired other promising treatments. For example, Dr. Rose Krajmalnik, a researcher studying the link between our guts and autism, took a page from
 
 C. difficile
 
 research and then took a calculated risk. To ensure her therapy worked long-term, she deconstructed her patients’ microbiomes and replaced them with a curated assortment of donated microbes. In a
 <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5264285/">
 clinical trial
 </a>
 aimed at treating autistic children with preexisting GI tract symptoms, Dr. Krajmalnik and her colleagues were able to reduce GI symptoms by 82%, and the destruction of the microbiome made room for new, beneficial species to grow and take foothold. They also observed 20-25% improvements in autistic behaviors: hyperactivity, anxiety, and speech patterns, among others. Somewhat miraculously, the treatment resulted in no negative side effects.


 Microbiome replacement isn’t without risks, though. “I do not want people to do this at home without (medical) supervision, because it could lead to bad GI infections… and the results might be different depending on what microbe donor you use,” she says.

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 If fecal and microbial transplants therapies are the present, Dr. Rogers predicts that synbiotics—a combination of synergistic probiotics and prebiotics—are the future.
 


 Even if microbiome transplants work, there is still a very real risk for infections from microbe donors. To get around these undetectable risks, synbiotics combine microbes, metabolites, and fiber in a more controlled pathogen-free manner. “As glamorous as it sounds, we can build poo in the laboratory, and install that into people.” Dr. Rogers says.


 Synbiotics have already demonstrated some promise in India, where researchers gave synbiotics to roughly 4,500 premature babies during the first few days of life. The synbiotics greatly reduced instances of sepsis and mortality.


 For more subtle effects, like managing anxiety and minor weight loss, it’s still too early to say whether any microbiome-augmentation benefits would be significant, or if they exist at all.


 “The microbiome could be argued to be one of the most important health and medical frontiers that we’ve reached for a long time,” Rogers says. “You can pay to have somebody analyze your microbiome,” but the increased self-obsession isn’t necessarily a fruitful endeavor. If you have the time and leisure to worry about your microbiome, Rogers says, “odds are you don’t have anything to worry about.”


 In the meantime, perhaps we should settle for some old advice supporting this unfolding health frontier—eat more vegetables, less fat, and, yes,
 <a href="https://www.ncbi.nlm.nih.gov/pubmed/28357027">
 exercise
 </a>
 .



 *Names have been changed to protect patient privacy.
 


 Image credits: CDC

Boosting beneficial microbes sounds simple enough, but the benefits for healthy people are hard to pin down.

We May Be Able to Outsmart Superbugs Using Their Own Defenses

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 Antibiotic-resistant superbugs are a looming menace to medicine, and now, some strains have evolved to eat the very compounds that try to kill them. Fortunately, a microbiologist may have discovered a way to use those very same microbes to devise new antibiotic approaches.
 
<figure class="richtext-image full-width">
<img alt="" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/penicillium_sp_257_14_microculture.width-990_Hzez8qL.jpg"/>
<figcaption>Penicillin itself is derived from a microbe called Penicillium, pictured here under the microscope. In nature, Penicillium is somewhat of a bully, using antibiotic to kill-off competitors for food and resources.
 
 </figcaption>
</figure>

 Although most drug-eating microbes aren’t disease-causing per say, Gautam Dantas, a microbiologist at Washington University in St. Louis and the lead author of a new study, recognized that shared strategies in antibiotic-resistant bugs could give us some innovative approaches to the ongoing superbugs arms race.
 

 By screening soil microbiomes for penicillin-degrading tools, researchers identified a cohort of compounds microbes use to neutralize antibiotic threats. Researcher Xiaohui Zhao from Univesity of Connecticut says that because there are patterns in how the enzymes cut antibiotics, this research could inform the design of new antibiotics. “Now that we understand which enzymes the bacteria use to disable the antibiotic, we can develop defense strategies and fight back,” Terrence Crofts, a postdoc who works with Dantas, wrote in The Conversation.
 

 Another approach would be treating new antibiotics with the enzyme, to examine whether new antibiotics could prevail in microbes who generally eat antibiotics. Additionally, by identifying crucial antibiotic-resistance components for example, scientists could devise ways to turn off antibiotic-eating enzymes in superbugs—ultimately stripping superbugs of their super-powers.
 

 But new antibiotics may not be the only way these microbes can help combat resistance. Since medical waste often contains large quantities of antibiotics, it’s common for microbes cohabiting with medical waste to develop antibiotic resistance. Intercepting the cycle, by preemptively neutralizing antibiotic waste with enzyme, could prevent disease-causing germs from spontaneously developing resistance in the waste environment.
 

 We wouldn’t have to add antibiotic-eating bacteria to the waste, either—just the enzymes themselves. Still, it wouldn’t be easy. Here’s Shawna Williams, reporting for The Scientist:
 
<blockquote>

 The idea is “very ambitious,” but such a system would likely be too expensive to make significant headway on cleaning up antibiotics in the environment, says Julian Davies, a microbiologist at the University of British Columbia in Vancouver who was not involved in the study.
 
</blockquote>

 Although it would cut costs, using microbes for enzyme factories is potentially risky, too, given that we’d be intentionally introducing antibiotic-resistant critters into the environment. In this case, the risk could be resistant microbes popping up in unexpected places—potentially neutralizing antibiotics in contexts where we’d still want antibiotics to work. In the future, this risk could be mitigated with a control
 <a href="https://www.wired.com/2015/12/kill-switches-gmos/">
 kill-switch
 </a>
 , but for now, directly applying just the enzyme may be the safest option.
 
</section>

 Photo credit:
 <a href="https://commons.wikimedia.org/wiki/File:Penicillium_sp_(257_14)_Microculture.jpg">
 Doc. RNDr. Josef Reischig, CSc. / Wikimedia Commons (CC BY-SA 3.0)
 </a>

The telescope would reconstruct a picture of the planet, pixel by pixel.

Scientists Want to Turn the Sun Into Massive Lens for a Telescope

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 Although manned space exploration to distant worlds is figuratively light-years away, our ability to glance across the heavens could be revolutionized with a technology that’s been right in front of our noses: the Sun.


 Current technology has given us
 <a href="https://apod.nasa.gov/apod/astropix.html">
 breathtaking
 </a>
 imagery, but to detect what’s hiding in deep space, telescopes are very limited—often resolving “tiny fuzzy dots” representing exoplanets larger than Jupiter. To obtain high-quality images of exoplanets quickly, astronomers are hoping to use the Sun as a colossal telescopic lens.


 The idea of this telescope, officially termed a “solar gravitational lens,” has been floating around for
 <a href="https://www.centauri-dreams.org/2006/08/18/the-focal-mission-to-the-suns-gravity-lens/">
 years
 </a>
 , but
 <a href="https://arxiv.org/pdf/1802.08421.pdf">
 a recent study
 </a>
 has breathed new life into the subject. Using up-to-date modeling, a group of researchers thoroughly evaluated the feasibility of a solar telescope, modeling the Sun’s gravitational waves and demonstrating a proof-of-concept image of Earth (above). If their predictions are accurate, we may soon have the resolution to see distant planetary surfaces, greatly improving our potential to detect exoplanetary life.


 Whether in a celestial telescope or your eye, all lenses perform a crucial, fundamental task: concentrate light from distant surroundings onto a small focal point. As the scientists illustrated in
 <a href="https://www.youtube.com/watch?v=Hjaj-Ig9jBs&amp;feature=youtu.be">
 this video
 </a>
 , the gravitational field of our sun doesn’t quite behave like a conventional lens. In addition to focusing light, the sun also gives off a tremendous amount of light, and could drown out important telescope information. To counteract this, scientist propose outfitting the scope with a carefully measured filter, blocking out the brightest parts of the sun to give distant exoplanet light a chance to be detected, concentrated, and ultimately focused.

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 Light isn’t the only problem: the sun’s gravity also bends and warps light around it, forming what scientists call an “Einstein ring,” named after the famed scientist who popularized the gravitational lens effect. The Einstein ring contains all the image information, and requires quite a bit of math to morph information back into a representative picture. However, by accumulating a series of Einstein ring-derived pixels, you could assemble them into a 1000×1000 pixel image. The resultant image would be unprecedented—what might be seen from a spaceship.


 The study is giving this idea traction, but to work, the solar gravitational lens telescope requires a probe to travel a minimum of 550 astronomical units. That’s 600 times the distance of earth to the sun—further than any probes in existence. However, with technologies like
 <a href="https://www.space.com/31063-electric-sail-solar-wind-space-exploration.html">
 e-sails
 </a>
 , which harness solar wind to travel nearly 20 astronomical units per year, a functional solar scope seems
 <a href="http://blogs.discovermagazine.com/outthere/2016/08/31/race-to-proxima-centauri/#.WqLp3JPwbgF">
 within
 </a>
 the grasp of our lifetime.

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 Image credit: DeLuca/Turyshev et al

Current technology has given us breathtaking imagery, but to detect what’s hiding in deep space, telescopes are very limited.

Thrombin (purple) is exposed after the DNA origami (grey) contacts cancer, promoting blood clots in vessels that feed tumors.

DNA Origamists Folded These Nanobots to Snuff Out Cancer

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 A few months back, bioengineers created the world’s tiniest rendition of the
 <a href="http://www.caltech.edu/news/worlds-smallest-mona-lisa-80563">
 Mona Lisa
 </a>
 using DNA origami. Now, building off of
 <a href="http://science.sciencemag.org/content/335/6070/831">
 prototypes
 </a>
 , Chinese and American scientists are
 <a href="https://www.nature.com/articles/nbt.4071.epdf?referrer_access_token=2zSa8gQKzkLv5BuPKFR_TdRgN0jAjWel9jnR3ZoTv0OFff8tYUk11oL1uI0KAIPb_28TGdYmortR12cel7viK7EyWTJqhhsP-1VpD5qhdw9H2yMk2ctHkOdPR40ghJT4swheYEuNVUkZ0Yb9NzSwd4XONJCYqgPBHWkuE-up2WWtom7el7S">
 using the technology
 </a>
 to snuff-out cancer with microscopic precision.


 If cancer is a criminal, blood vessels are its accomplice. Not only do they feed and nurture cancer, promoting its survival, but they also help shuttle cancer cells to rest of the body, sowing the seeds of metastasis. Scientists can identify these accomplices through a protein structure called
 <a href="http://www.eurekaselect.com/118117/article">
 nucleolin
 </a>
 ; it’s built right into the walls of blood vessels that feed cancer, and also attracts a specific DNA sequence, making it easy to target.


 The DNA-origamists coded the cancer-targeting DNA into a DNA nanobot and armed it with a weapon familiar to anyone who’s ever scraped their knee—thrombin. Thrombin is a blood clotting catalyst which stops our wounds from bleeding. It does so by triggering the formation of blood-capturing nets, and for years, doctors have spritzed it onto surgical sites to limit blood-loss.


 In theory, this reliable coagulant could cut-off cancer’s resources, but injecting thrombin itself into the circulatory system is deadly—too many blood clots can lead to strokes, pulmonary embolisms, and more. To make thrombin an effective cancer treatment, scientists must conceal it right up until it contacts the cancer.

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 So DNA-origamists folded a paper-like mesh of DNA into a neatly shaped tube that wraps around the thrombin like a taquito. The outer surface is coated with cancer-targeting DNA. Once DNA hits the cancer’s blood vessels, the origami quickly inverts itself, revealing the thrombin and sparking a cascade of events that isolates tumors.


 Test runs of the treatment in tumor-laden mice have cut off a cancer’s blood supply, stifling tumor growth and effectively starving cancer to death. The nanobots small size makes them ideal for spotting cancer cells that would evade detection by surgeons. And, in theory, it is more specific to tumors than chemotherapy—allowing regenerating non-cancer cells (such as hair) to survive the treatment.


 Currently, researchers are still evaluating the safety of this new technology. Considering that some cancers themselves are decorated with the telltale structure nucleolin, the DNA-origami approach seems promising – but nucleolin protein is also present inside non-cancer cells. When healthy cells break open and release their guts into the bloodstream, it’s possible origami nanobots could be triggered, releasing their thrombin and forming clots in otherwise healthy parts of the body. Another important obstacle is removing unwanted nanobots from a patient, if at all. Thus far, the DNA nanobots haven’t raised an immune response in pigs or mice—a potentially problematic outcome—although these experiments followed animal health for a brief five-day period. Surely, time will tell if this new technology is safe enough for human patients – and it may not be long before we see it enter clinical trials.

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 Image credit: Jason Drees, Arizona State University

Chinese and American scientists are using DNA origami technology to snuff-out cancer with microscopic precision.

Similar to herd-immunity for vaccinations, scientists propose that GMO crops act as a pest-absorbing sink.

GMO Crops Have an Unintended Side-Effect: Protecting Non-GMOs

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 GMOs have a
 <a href="https://www.npr.org/sections/thesalt/2012/10/18/163034053/top-five-myths-of-genetically-modified-seeds-busted">
 bad reputation
 </a>
 , but 20 years after they were first planted in farm fields, they are having an unintended side effect: helping non-GMO crops.


 Many genetically modified organisms were engineered with insect-killing proteins to eliminate or reduce the use of pesticides. The most widely used insect-killing protein comes from a microbe called Bacillus thuringiensis (often abbreviated “Bt”), and the hazards associated with seem largely
 <a href="http://www.who.int/foodsafety/areas_work/food-technology/faq-genetically-modified-food/en/">
 limited to insects
 </a>
 . Since the first Bt crop was planted in 1996, GMOs have been immune to the corn borer and earworm pests-nicknamed the “scourges of corn.”


 To prevent Bt-resistance in these pests and to confine GMO genes to their intended crops, the EPA mandates farmers plant non-GMO plants around the periphery of GMO fields- a moat of sorts.

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 But the corn in those moats are also receiving the benefit of genetic modification, even if the plants themselves aren’t altered. In a new study, which examined the landscapes of pests radiating from GMO crops, researchers found that GMO crops are enabling non-GMOs to flourish with fewer pesticides. New Jersey’s non-GMO green beans and peppers crops, for example, reduced pesticide use by 85% since GMOs were introduced.


 Similar to herd-immunity for vaccinations, scientists propose that GMO crops act as a pest-absorbing sink. With the number of pests dialed down, farmers can spray fewer pesticides onto non-GMO foods. This unprecedented finding translates into fewer pesticides in the environment-and unlike GMOs, pesticides have well-known
 <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4947579/pdf/fpubh-04-00148.pdf">
 health and environmental hazards
 </a>
 .


 Farmers can apply this knowledge to maximize the benefits. For example, farmers could plant other vegetables in close proximity to Bt corn, reducing the need for pesticide applications. Other pest-prone produce, such as potatoes, could also be spared spoilage by being planted in close proximity to GMOs.

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 Photo credit: public domain

In a new study, which examined the landscapes of pests radiating from GMO crops, researchers found that GMO crops are enabling non-GMOs to flourish with fewer pesticides.

Tiffany Dill

Articles