Field of Science


The Shambulance: Laser Lipo Only Kind of Sucks

The Shambulance is an occasional series in which I try to find the truth behind overhyped or bogus health products. With me at the reins are Steven Swoap and Daniel Lynch, both of Williams College.

People selling no-suction liposuction are not totally sure what they're offering you. "Low levels of visible red laser light...create a safe and painless bio-stimulation effect," says one center. "Transitory pores" open in the fat cells, sending their contents out for "detoxification," says another, adding that the process is "almost exactly the same as exercise." Except for the lasers.

Despite the confusion, laser lipo does—seemingly, in some ways—work. Wait! Don't panic. Put away your wallet and let's talk about it.

"This is not a weight loss therapy," says Williams College physiologist Steven Swoap. At best, it's "a redistribution of fat therapy."

Many spas offer treatment with a specific laser system called i-lipo. The FDA approved this device in 2012 "for non-invasive aesthetic treatment for the temporary reduction in circumference of the waist."

It's "non-invasive" as opposed to something called laser-assisted liposuction, where doctors blast your fat with a laser before actually cutting into you and sucking it out. What about the rest? "Aesthetic" is because this is meant to change your looks—not to address any health problems. "Temporary," because the FDA based their approval on a study lasting just a few weeks. If you want your new waist shape to last longer, they're not making any promises. And, of course, "reduction in circumference"—but not loss of weight. Something inside you may move around, but that doesn't mean it's going away.

FDA approval was based on a placebo-controlled study in which some participants had a fake laser treatment. After eight sessions over three to four weeks—each session followed by a required workout—the group getting real laser treatment had lost almost an inch and a half more from their waists than the placebo group. (If anybody finds this study itself, and not just a PR summary, I'd love to see it.)

As for how it works, the FDA approval statement says that laser energy "promotes disruption" of fat cells, making them release their contents. But a 2013 review paper says that "the mechanism of action of LLLT [low-level laser therapy] on fat remains somewhat controversial." Various scientists have suggested that the laser makes tiny pores open in the fat cells to release fats; that the cells themselves are destroyed; or that the laser stimulates your cells' machinery to start breaking down fats and discarding their components. There are challenges to the evidence in every camp.

"The use of lasers to essentially heat the fat seems a bit dubious," says Williams College biochemist Daniel Lynch. He's curious whether the results could really be coming from changes in water and salt balance in heated areas of the body. "I wonder if similar effects could be obtained simply [with] heating pads," he adds. Actually, the so-called infrared body wraps offered by some spas aren't far off—these places wrap clients in heated pads and report inches lost after all the squishing and sweating is over.

Assuming that the procedure does kick fat out of your cells, many spas recommend that you exercise immediately afterward. You need to burn up that wandering fat right away, they warn, or else it will just find its way home to your belly.

Lynch agrees that mild exercise afterward would help you use up any fats that the laser has shaken loose. Swoap points out that when we do tougher exercise, our bodies switch to using carbs as fuel instead of fats—so an intense workout right after laser treatment would be less helpful than a tame one. Either way, if fatty acids travel to your liver, it will likely send them right back into storage in your body's squishy areas.

Even if you manage to lose fat from your midsection, you may not be doing yourself any favors in the long term. "Certain types and locations of fat are beneficial, whereas others are harmful," Swoap says. The fat that's reachable by liposuction—laser or traditional—is "subcutaneous" fat, just under your skin. "Subcutaneous fat is a good fat—[it provides] insulation, cushioning, even endocrine function," Swoap says.

"Liposuction is, unfortunately, removing mainly subcutaneous 'good fat' in the name of body sculpting and body image," Lynch agrees.

The fat that's harmful to your health is "visceral" fat, the stuff wrapped around your organs. And if you suck out subcutaneous fat, your body may respond by hiding more fat where you can't reach it.

A 2011 study found that one year after surgical liposuction in their thighs and bellies, women had regained their lost fat—and stored more of it into their abdomens than originally. In 2012, a different research group found that six months after abdominal lipo, women's visceral fat had increased by 10%. This was prevented if they followed an exercise program.

So laser lipo may shrink your waist a little, if you exercise every time you do it. And fat removed surgically might not reappear to strangle your organs, as long as you keep exercising after liposuction. There's no word yet on whether laser lipo can also lead to more visceral fat, but to be safe you might just want to keep working out after it's done.

Maybe the people who called this treatment "almost exactly like exercise" were closer than they knew.

Image: NU:U Laser Lipo Centers

Why a Lost Baby Seal May Soon Be at Your Doorstep

Every host knows when you run out of ice, the party's over. For young seals surviving on ice floes, the festivities are breaking up sooner than they used to. That sends vulnerable youngsters into the ocean before they're ready—maybe to end up stranded on a beach near you.

To keep their young from becoming drifting bait in a predator-filled ocean, female harp seals give birth on top of winter sea ice. The pups stay on the ice, undercover in a coat of white fur, until they're old enough to survive in the ocean. Then they shed their white coats, dive in, and begin migrating with the rest of their population.

Harp seals live in two main populations, one on either side of the northern Atlantic. From the population on this side of the pond, increasing numbers of seals have been showing up stranded along the U.S. coast, from Maine all the way down to North Carolina. Researchers at Duke University looked for patterns in these strandings—more than 3,000 over the past two decades.

Not too surprisingly, there was a clear relationship between strandings and the amount of sea ice. Years with more ice had fewer strandings. In years with less ice, when melting floes might force pups into the water before they're ready, strandings went up.

The same trend didn't apply to adults, however. Strandings of adult harp seals weren't linked to the amount of sea ice in that year. But in all years, the majority of stranded seals were pups. That means fluctuations in sea ice have the strongest effect on young harp seals.

The researchers also saw that males were more likely to strand than females. This may be due to what they call a "tendency to wander" among males. Brianne Soulen, one of the paper's lead authors, adds that because adult females need to spend more energy on things like pregnancy, they're less likely to stray from safe feeding grounds.

Genetic factors may also be at work. Soulen says they found slightly less genetic diversity among males, which in theory could make them more susceptible to disease or other factors. No matter the reason, if a harp seal does wind up on the shore of your local beach, it's likely to be a baby boy. Get blue balloons.

In the most recent years included in the study, 2009 and 2010, the usual pattern didn't hold up. The year 2010 was bad for ice, but didn't have a lot of strandings. However, Soulen doesn't see this as reason for optimism. An earlier study saw harp seals changing their migratory behavior in response to shifting ice cover; they may simply be stranding someplace else now, where they're not counted. Or the population as a whole may have dropped dramatically.

It matters, of course, because the ice is running out everywhere. Despite year-to-year fluctuation, the authors write, ice cover in the North Atlantic is disappearing at up to 6% per decade. And Soulen says what's happening with the harp seals provides a big hint about the state of other marine mammals. "Harp seals are a good representative species of the effects of ice changes." The hooded seal population in the western North Atlantic, for example, has declined by 90% since the 1940s, as ice there has steadily disappeared.

When sea ice is gone, there's no one who can dash out for more. The party may not be over quite yet, but it's getting pretty lame.

Image: courtesy of the International Fund for Animal Welfare

Brianne K. Soulen, Kristina Cammen, Thomas F. Schultz, & David W. Johnston (2013). Factors Affecting Harp Seal (Pagophilus groenlandicus) Strandings in the Northwest Atlantic PLOS ONE DOI: 10.1371/journal.pone.0068779

Uncoordinated Eyeballs Keep Kids from Reading like Adults

Before new readers can move from Dr. Seuss to Doctor Zhivago, it's not only their vocabulary and appreciation of the Russian aesthetic that have to mature. Young eyes just don't move across words as easily as older eyes do. Like Thing One and Thing Two, the eyes bounce around independently and cause disorder.

The difference is in saccades, the little horizontal or vertical hops that ratchet our eyes through sentences. French researchers Magali Seassau of e(ye)BRAIN and Maria-Pia Bucci of Hôpital Robert Debré have been studying how this system develops in kids, including those with dyslexia.

For their latest study, the authors gathered 69 kids ages 6 to 15, as well as 10 adults. While using an eye-tracking device, the subjects silently read a paragraph of text from an age-targeted book. (Experimenters asked questions afterward to make sure the kids had actually read it.) In a separate task, subjects were given the same paragraph—except that all the vowels had been replaced by consonants. They had to skim the text and count the number of r's.

Seassau and Bucci saw evidence of several ways in which a person's reading machinery gets more efficient with age. As subjects got older, they made fewer saccades: their eyes took bigger, smoother jumps forward through the text, and fewer backward jumps. They also paused for less time in between leaps.

These findings fit with what the researchers had seen in earlier studies of reading. "The process becomes automatic" as kids age, Seassau says. "Reading gets to be faster, better and easier."

Younger kids are also worse than older kids or adults at keeping their two eyes coordinated with each other. This means saccades happen unevenly. In kids, "Eyes aren't coordinated when they jump forward on the letter or on the word," Seassau explains. Like competitors in a three-legged race, the eyes have to learn how to match their stride if they want to reach the finish line quickly.

Whether subjects were reading words or searching nonsense text for a certain letter, they got faster with age. Yet there were revealing differences in how their eyes and brains handled the two tasks.

Adults were faster and more accurate at reading than at searching. In the search task, their eyes worked inefficiently, making more saccades. The same thing was true of kids 10 and older. But kids ages 6 to 9 made the same number of jumps whether they were reading real words or hunting for letters in the nonsense paragraph. Younger kids read more like it's a scavenger hunt; older kids and adults read like they're running on a track. The results are in PLOS ONE.

None of the kids or adults in this study had unusual reading difficulties, but Seassau and Bucci are planning to expand their current research to kids with dyslexia in different countries. Earlier eye-tracking studies have hinted that dyslexic kids move their eyes through text in an immature, uncoordinated way. Learning more about how they read may help get everyone's eyes acting their age.

Images: Peter Rohleder (via Flickr); Seassau and Bucci.

Magali Seassau, & Maria-Pia Bucci (2013). Reading and Visual Search: A Developmental Study in Normal Children PLOS ONE DOI: 10.1371/journal.pone.0070261

Swapping Bodies with a Child Makes Everything Seem Bigger

Remember revisiting your preschool or kindergarten classroom once you were older, and realizing all those tables and sinks that are normal-sized in your memory were actually miniature? And that the giant hill you used to struggle up is more of a mound? Adults can regain that feeling of living in an oversize world just by putting on a virtual-reality headset. (Large kid who used to budge you in line for the slide not included.)

This is the latest spinoff of the rubber-hand illusion, a phenomenon in which watching a rubber hand being stroked with a paintbrush, while you feel a matching sensation on your own hand, creates an eerie sensation that the rubber hand is your own. Another recent study found that kids experience the illusion more strongly than adults. Aside from being a neat party trick, the research may have implications for amputees who experience phantom limbs.

The illusion's newest incarnation, by Mel Slater at the University of Barcelona and others, didn't use any physical contact. Instead, subjects wore virtual-reality goggles that let them see through the eyes of a virtual body. The avatar's movements were matched to their own with motion tracking, and subjects could watch their virtual bodies in a mirror while they moved and stretched.

Although the virtual body matched a subject's movements, it didn't match his or her size. The avatars were all miniature people--either a child about four years old, or an adult scaled down to the same height.

With either kind of small body, subjects reported that they felt an illusion that the avatar's body was their own. Researchers quantified this by having subjects look at different-sized objects in the virtual world and hold out their hands to indicate how wide the objects were. (For this part of the experiment, they couldn't see their virtual hands.)

Size perception is always tied to the size of your own body, Slater says, so all subjects overestimated the size of the objects they saw. The same thing happened in an earlier rubber-hand study that had subjects inhabiting both tiny and giant bodies.

But with a child's body, the effect was significantly greater, the authors report in PNAS. People virtually inhabiting a four-year-old's body perceived objects as even larger than people inhabiting a small adult body did.

The authors think this may be because the experiment triggers specific, first-person memories of being in a child's body. Living in a miniature adult body, of course, is a less common experience. This is a "possible new discovery," Slater says—"that the brain codes for body type, not just for size."

Slater has experienced the illusion himself. "It is very powerful and strange to see yourself in a mirror as a small child," he says. Maybe stranger, even, than those tiny sinks.

Image: Slater et al. (from supplemental movie)

Domna Banakou, Raphaela Groten, & Mel Slater (2013). Illusory ownership of a virtual child body causes overestimation of object sizes and implicit attitude changes PNAS DOI: 10.1073/pnas.1306779110

Loons Choose Homes That Remind Them of Where They Grew Up

Before settling down to have chicks of its own, a young adult loon shops around. It visits different lakes, swimming in them to test the water. Finally it chooses a home. Rather than selecting the best neighborhood in which to raise its young, though, the loon seems to pick a place that feels comfortably like where it grew up. If it's not the best place to raise kids, too bad.

Walter Piper, a biologist at Chapman University in California, has been chasing loons in Wisconsin for more than two decades. "It might seem like self-flagellation," he admits. Loons are a difficult study species, in that they tend to dive straight down into the water when a human approaches. Piper and his colleagues followed the aquatic birds between 1991 and 2012, snagging them with fishing nets and banding their young, and were able to build a detailed, multi-generation history of bird real estate decisions.

Common loons (Gavia immer) grow up in nests on the water tended by two parents. When they reach adulthood, they migrate over the winter and then return to make their own homes for breeding. The study area in Wisconsin is dotted with small glacial lakes, and breeding pairs of loons often claim an entire one of these lakes as their own territory.

When it comes time to choose an adult home, young loons that are thinking of the children ought to choose large lakes with a high pH; these have been shown to produce larger numbers of healthier chicks. Yet the adults don't always pick those prime locations.

The researchers tracked the movements of their loon subjects, as well as various qualities of the lakes they moved between: shape, depth, clarity of the water, and so on. They also ran computer simulations to see where loons might end up if they chose their new habitats randomly. Instead, they found that loons tended to choose lakes that were similar to where they grew up, both in the pH of the water and in overall size.

How do house-hunting loons find lakes with the qualities they care about? Piper says loons are adept at judging the size of a lake from the air, since they're big birds that need a lot of "runway" to take off from. If they land in a too-small body of water, they'll get trapped there. As for pH, he acknowledges, "We do not see loons using pH meters or pH paper." But the types of fish, insects and so on that live in a lake correlate to its acidity or alkalinity. This mix of prey species is probably one thing loons are judging when they shop around for a home.

Piper thinks loons must benefit from choosing lakes that are more like where they were raised, even if these aren't the lakes that produce the most chicks right away. Perhaps by choosing someplace similar to their old hunting grounds, they make it easier to find food. This might allow the loons to survive for more years, ultimately making up for their original disadvantage in number of chicks.

"Our finding shows that animals sometimes DO NOT pick the habitat that promises greatest reproductive success," Piper says. He thinks other scientists studying how animals choose homes should focus more on parents, rather than their offspring.

And when loon chicks complain about their habitat, their parents can tell them, "Back in my day we lived on a tiny lake and we liked it! There were even these people chasing us around with fishing nets..."

Image: by Ano Lobb (via Wikimedia Commons)

Piper WH, Palmer MW, Banfield N, & Meyer MW (2013). Can settlement in natal-like habitat explain maladaptive habitat selection? Proceedings. Biological sciences / The Royal Society, 280 (1765) PMID: 23804619

Hack Your Workout: These Songs Make People Take Bigger Steps

Do you have a workout playlist? You may find yourself matching the stride of your power walk to the beat in your earbuds—but tempo isn't the only thing affecting how fast you go. Certain musical pieces seem to make people take longer strides, even while walking to the same beat. (Spoiler alert: Aqua.)

Marc Leman is a musicologist at Ghent University in Belgium. With his colleagues, he created a list of 52 songs with a tempo of 130 beats per minute, a speed they chose based on previous research. The playlist included a variety of genres, and all the songs were in 4/4 time.

Then the researchers gathered 18 "normally built" adults, strapped sensors to their legs, and sent them walking laps around a gymnasium. The subjects were explicitly told to walk in time to the beat of the music. Through headphones, they heard 30-second clips of the different songs, with periodic interludes of only a metronome sound.

Although all the music had the same tempo of 130 beats per minute—which subjects stepped in time with—their actual walking speed varied as they took longer or shorter strides. Leman says that to certain songs, people walked 10 percent faster than they did to others (or to the metronome beat).

The researchers dubbed the fastest-walking songs "activating," and the songs that made people walk slowest "relaxing." The full playlist is here, ranked from most relaxing to most activating. These were the top 10 most relaxing songs, to which walkers made the least forward progress:

And here are the tunes to which people covered the most ground:

Right around the middle was "Dragostea din tei," better known by some as "the Numa Numa song." Test subjects probably got slowed down by the requisite arm flailing.

Separately, the researchers asked subjects to rate the musical selections on a variety of adjectives: Was the song happy or sad? Tender or aggressive? Known or unknown to the listener?

Some of the responses were tied to how speedily the songs made them walk. For example, pieces described as "stuttering" rather than "flowing" made people take shorter strides. Pieces that subjects found especially "aggressive" or "loud" (although the volumes of all the songs had been matched in their headphones) made people walk faster. So did songs they described as "bad" rather than "good." (This may explain "Barbie Girl").

The musicologists, meanwhile, tried to find more scientific explanations for the powers of certain songs. Leman says this was surprisingly difficult. They did find that more activating songs tended to have simpler melodies, with fewer notes per beat. These pieces often had a strong bass line, as well as clear downbeats ("one two three four..."). The group is still working on figuring out what kinds of music make people move the fastest.

For his own exercise playlist, Leman is a fan of jazz, though he says it's not always great at getting a person moving. He thinks syncopation, which interrupts the regular beat of the music, is an important factor in making a piece relaxing rather than activating. Instead of marching straight ahead, syncopated jazz music seems to encourage you to walk with more horizontal motion, Leman says: "You want to swing."

Image: by Malingering (via Flickr)

Marc Leman, Dirk Moelants, Matthias Varewyck, Frederik Styns, Leon van Noorden, & Jean-Pierre Martens (2013). Activating and Relaxing Music Entrains the Speed of Beat Synchronized Walking PLOS ONE DOI: 10.1371/journal.pone.0067932

Decapitated Worms Regrow Heads with Memories Still Inside

How good are you at remembering something you learned two weeks earlier? What if during the intervening 14 days, your head was removed? One flatworm isn't bothered by this scenario. After growing back its entire head and brain, it picks off pretty much where it left off.

The planarian is a modest little flatworm, the kind of common microscope denizen you might find in a Gary Larson cartoon. What's remarkable about it is its ability to regenerate. The whole body can regrow, head to eyespots to tail, from even a tiny fragment of the original animal.

Tal Shomrat and Michael Levin at Tufts University built a computerized apparatus for training planarians. Back in the 1960s, an intriguing line of research had suggested that the worms might be able to retain memories after decapitation. But researchers had done their training and testing by hand, a cumbersome method that led to inconsistent results. ("The process of training worms by hand is very time-consuming," Levin says, probably understating it.) Ultimately, the topic was abandoned. Now, with a totally automated procedure, Shomrat and Levin hoped to study planarian memory with less error and greater numbers of worms.

First, their worms spent 10 days getting familiar with one kind of environment, either a regular petri dish or one with a rough floor. They were fed abundantly so that they'd learn a positive association with their home environment. Then, for testing, they were put in a rough-bottomed dish with a little spot of food in the center and a light shining on it. Planarians like to stick to the periphery, and they hate light, so they needed to overcome both aversions to get the food. As expected, worms that were more familiar with the rough dishes reached the food sooner, as measured by video tracking.

When the researchers tested the worms again 14 days later, they found that the worms trained on a rough-bottomed dish were still more comfortable with it than the other worms. This memory seemed to last for at least two weeks. Perfect—that's just enough time for a planarian to lose its head and grow it back.

The worms were relieved of their heads. The scientists made certain that no bit of brain survived. Then, after the worm stumps had painstakingly re-headed themselves, the planarians went back into the testing chamber.

The memory wasn't there right away. But Levin and Shomrat found that if they gave all the worms one quick training session before testing, worms who'd previously been familiarized with rough petri dishes reached the food significantly faster than the other worms. The training session "basically allowed the worms to refresh their memory of what they had learned before decapitation," Levin says. In other words, their memories had survived the loss and regrowth of their heads.

Levin doesn't know how to explain this. He says epigenetics may play a role—modifications to an organism's DNA that dial certain genes up or down—"but this alone doesn't begin to explain it."

It's a mystery, Levin says, how a chemical tweak somewhere outside of a worm's brain can later be translated into information, such as the knowledge that a bumpy environment means food is nearby. "We don't have an answer to this," he says. "What we do show evidence of is the remarkable fact that memory seems to be stored outside the brain."

Image: Shomrat and Levin.

Tal Shomrat, & Michael Levin (2013). An automated training paradigm reveals long-term memory in planaria and its persistence through head regeneration The Journal of Experimental Biology : 10.1242/​jeb.087809

Help Desk: Chastity Belts and Other FAQs


I'm on vacation this week. With any luck, as you read this I will be lying in the shade with a book or having a hilarious misunderstanding with a non–English speaker. I will not be thinking about en-dashes, as I did just now. I will try not to think about beige liquid diets.

While I am away, please refer to these FAQs for any concerns you might have. They're not Frequently Asked Questions so much as Fairly Awkward Queries: search terms that, through some whim of a Google or Bing algorithm, brought people to this blog. I hope that their questions were answered eventually—or, at least, that they're enjoying their summers.

are cuckoo birds real
Yes, unlike the dragon dishwasher or manticore microwave, the cuckoo clock is an appliance based on a real animal. 

how to outsmart an 8 year old
Nineties Trivial Pursuit?

covered in bees 
If your hands are free to type, I have to think you're overstating the severity of the situation. At best you're sprinkled in bees.

a mutation of a lion and a monkey
I'm not sure about the lonkey, but you can see some other imaginary animal hybrids in this gallery at Wired. (I contributed the suggestion for the cuttlephant.)

chastity belt for 2 months

I'm sorry to hear about that.

been in a chastity belt for 9 months
Do you have any advice you'd share with a seven-months-earlier version of yourself?

chastity belt why on why now
I knew I'd regret this post.

fish adoption form
I've never tried this personally, but I'm pretty sure they just let you take them home from the store in a plastic bag.

orangutan tool use fish
Is the orangutan using the fish as a tool? Is the fish using the orangutan? Is this why you wanted to adopt it?

pretending to be paraplegic 
I'm going to stop you right there and say there HAS to be a better way to make your Match profile stand out.

i draw worms out of the ground
Maybe you could be a new X-Man? Like Storm, but Worm? Though in a different comic universe, if Robin is your sidekick, this could be distracting.

miniature poodle evolved
It was survival of the fittest in the Tundra of Purses, and once the miniature poodle had developed its portable stature and warm, hypoallergenic coat, it dominated its niche.

what do polar bears hate
Wild tundra poodles.

where baby point in female 

a real octopuses that tie you up
Ooh! This might be a good tactic to try on that 8-year-old.

unicorn horns photo 
I'm afraid I have some bad news.

Previously: Help Desk, Relationship Edition; 12 Days of Inkfish, Day 4: Help Desk

Image: Aryc Ogre (via Flickr)