Tag Archives: calcium

Venus flytrap with no brain or nervous system senses prey with short-memory trick

 The trap of a Venus fly trap, showing trigger hairs. Credit: Wikimedia Commons.

The Venus flytrap is famous for its unusual ability to catch and digest insects and other small animals. And although it has no brain or nervous system to speak of, its behavior is strikingly intelligent. The carnivorous plant has tiny hairs that line its maw, which act like motion sensors, detecting when a struggling insect is ripe for the picking so it can close its jaws and ramp up digestion. But if raindrops or other false alarms trigger the hairs, the trap remains open thereby preserving energy.

This remarkable ability is owed to the plant’s short-term memory. Previous research shows that Venus flytraps can effectively ‘count’ to five. For instance, two touches of the hairs within a 20-second window of time cause the trap to shut while five touches boost the production of digestive enzymes.

How the plant records these instances of touch has so far been a mystery, but a new study published this week in the journal Nature Plantsmay shed some light.

Poke this plant and you’ll be in for a surprise

According to researchers at the National Institute for Basic Biology in Ozaki, Japan, Venus flytraps owe their short-term memory to calcium signaling. This is a hypothesis that had been suggested before but it is only now that calcium’s role has been confirmed thanks to genetic engineering.

Venus flytraps were engineered to produce a fluorescent protein that glows green when it’s exposed to calcium. When the plants’ sensory hairs were gently stimulated, the base of the hairs began glowing. The glow quickly spread through the entire leaf before starting to fade. When the hair was touched a second time within 30 seconds or so, the leaves lit even brighter. What’s more, the trap quickly snapped shut. Check out the amazing video below for this effect in action.


These experiments show that the flytrap’s short-memory is predicated on calcium levels in the plant’s leaves. When the calcium concentration in cells reaches a certain threshold, the trap closes.

“I tried so many experiments over two and a half years but all failed. The Venus flytrap was such an attractive system that I did not give up. I finally noticed that foreign DNA integrated with high efficiency into the Venus flytrap grown in the dark. It was a small but indispensable clue,” Hiraku Suda, the first author of the article, said in a statement.

Visualization of the changes in intracellular calcium concentration of the Venus flytrap. Credit: NIBB.

In the future, the Japanese researchers want to use the same method to study other aspects of the Venus flytrap’s behavior, such as the capturing of prey and digestion.

“This is the first step towards revealing the evolution of plant movement and carnivory, as well as the underlying mechanisms. Many plants and animals have interesting but unexplored biological peculiarities,” said Mitsuyasu Hasebe of the National Institute for Basic Biology.

Thank exploding stars for your teeth and bones

Artist’s interpretation of the calcium-rich supernova 2019ehk. Credit: Aaron M. Geller/Northwestern University

Astronomer Carl Sagan once famously said that “we are all made of star stuff”. This statement poetically sums up the fact that the carbon, nitrogen and oxygen atoms in our bodies, as well as atoms of all other heavy elements, were forged inside previous generations of stars.

According to a new study, about half of the calcium in the universe was dispersed by supernovae — huge explosions that occur at the end of a massive star’s lifetime, when its nuclear fuel is exhausted and it is no longer supported by the release of nuclear energy.

Happy accidents

Astronomers have always been aware that supernovae are responsible for creating and dispersing heavy elements like gold or platinum. However, the fusion of calcium has always been something of a mystery due to lacking evidence. The fact that supernovae observations are so rare made the challenge even greater.

But as it sometimes happens, a happy accident got the researchers out of a rut. Last year, Joel Shepherd, an amateur astronomer, noticed a bright burst with his telescope while he was observing the Messier 100 spiral galaxy.

Shepherd immediately shared his observations with the astronomy community, which quickly identified the bright orange dot as a supernova — and what a rare occasion, since the sighting was made within hours of an explosion.

Follow-up observations of the stellar explosion, known as SN2019ehk, were performed by NASA’s orbiting Neil Gehrels Swift Observatory, the Lick Observatory in California, and the W.M. Keck Observatory in Hawaii in optical light. The Swift observatory performed X-ray and ultraviolet light observations of the event, which revealed it was a calcium-rich supernova.

Hubble Space Telescope image of SN 2019ehk in its spiral host galaxy, Messier 100. The image is a composite made of pre- and post-explosion images. Credit: CTIO/SOAR/NOIRLab/NSF/AURA/Northwestern University/C. Kilpatrick/University of California Santa Cruz/NASA-ESA Hubble Space Telescope.

According to the study published in The Astrophysical Journal by an international team of more than 70 scientists, stars responsible for calcium-rich supernovae shed layers of the mineral in the last months before the explosion. The heat and pressure of the supernova are what actually drives the fusion of calcium.

“Calcium-rich supernovae are so few in number that we have never known what produced them,” said Dr. Wynn Jacobson-Galan, a researcher at Northwestern University.

“By observing what this star did in its final month before it reached its critical, tumultuous end, we peered into a place previously unexplored, opening new avenues of study within transient science.”

Typically, stars generate small amounts of calcium as they burn through their helium supply. However, the new study shows that copious amounts of calcium are created and released within a matter of seconds by supernovae.

“Before this event, we had indirect information about what calcium-rich supernovae might or might not be. Now, we can confidently rule out several possibilities,” said Dr. Raffaella Margutti, also from Northwestern University.

“The explosion is trying to cool down. It wants to give away its energy, and calcium emission is an efficient way to do that,” Dr. Margutti said.

Although the Hubble Space Telescope had been observing M100 for the past 25 years, it somehow missed SN2019ehk’s brief luminosity. Luckily, one keen astronomer was up to the challenge, a marvelous discovery followed out of it. Subsequent observations with Hubble of the supernova site also revealed clues about the former star’s true nature.

“It was likely a white dwarf or very low-mass massive star,” Jacobson-Galan said. “Both of those would be very faint.”

“Without this explosion, you wouldn’t know that anything was ever there,” Margutti added. “Not even Hubble could see it.”

Calcium-based batteries could be a step closer to reality

Manufacturing calcium-based batteries could be a step closer thanks to a newly synthesized chemical discovered by researchers at the Helmholtz Institute Ulm in Germany, looking for a safer and cheaper alternative than the current lithium-based batteries.

A calcium reservoir. Credit: Wikipedia Commons

Until now, researchers working on calcium batteries have lacked a suitable electrolyte, the medium through which electrical charge flows. Batteries with anodes made of calcium — a more abundant substance — might be more sustainable and safer than batteries with lithium anodes.

Researcher Zhirong Zhao-Karger and her colleagues reacted a calcium compound with a fluorine-containing compound to create a new type of calcium salt. The resulting material conducted electricity more effectively than any calcium-based electrolyte yet reported. It also efficiently conducted ions at a higher voltage than other calcium-based electrolytes.

Lithium, now used in most electrochemical storage systems and electronic devices, is relatively expensive because of limited supplies and has technical disadvantages. The lithium-ion batteries have numerous drawbacks: they sometimes catch fire, and they depend on increasingly scarce and toxic substances such as lithium and cobalt.

To create lithium batteries, there is a need for a range of rare earth metals that require heavy mining and manufacturing that emit significant emissions. Furthermore, major components such as lithium, nickel, and cobalt exist in a finite amount that is unlikely to meet the current and future demands for battery units.

Meanwhile, calcium-ion batteries, long tipped as a viable replacement, have at least twice the number of electrons as lithium units, which means higher power density in a thinner, lighter package.

Calcium is about 2,500 times as abundant as lithium in nature, making the calcium-ion energy storage technology a promising candidate for next-generation batteries due to its high performance and low cost. However, calcium-ion batteries have been unsuccessful to attain a satisfactory performance in previous studies.

The search for alternatives to lithium batteries is mostly due to demand for extended-range electric vehicles and batteries for portable gadgets that can give a longer life span, as well as a need to reduce manufacturing costs.

Electric vehicles are set to make up more than half of global passenger car sales by 2040 and completely dominate the bus market, according to this year’s Electric Vehicle Outlook report.

Electrics will take up 57% of the global passenger car sales by 2040, with electric buses dominating their sector, holding 81% of municipal bus sales by the same date. Electric models will also make up 56% of light commercial vehicle sales.

Photograph of the holotype of Avimaia schweitzerae. Credit: Barbara Marrs.

Paleontologists find 110-million-year-old bird fossil with unlaid egg still inside it

Photograph of the holotype of Avimaia schweitzerae. Credit: Barbara Marrs.

Photograph of the holotype of Avimaia schweitzerae. Credit: Barbara Marrs.

A crushed, pancake-like fossil unearthed in northwestern China contains both a bird and its unlaid egg. The fossil also features a medullary bone — a special type of tissue which serves as a readily available store of calcium for the eggshell. This is the first time scientists have found such a bone and an egg together in the same fossil. Ironically, the authors say that the egg is what seems to have killed the mother.

Insight into the reproductive life of ancient birds

The new species, called Avimaia schweitzerae, belongs to a family of ancient birds known as Enantiornithes, which lived alongside their dinosaur cousins for more than 100 million years. Enantiornithine birds were widely distributed across the globe, with remains found in Argentina, North America, Mexico, Mongolia, Australia, Spain, and China. Paleontologists take a special interest in enantiornithines because the species includes both specialized and primitive features, suggesting they represent an evolutionary side branch of early avian evolution.

Paleontologists at the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences found bits of eggshell preserved alongside the ancient bird’s fossilized skeleton. These eggshell fragments were detected inside the specimen’s abdomen, showing parts of the egg membrane and cuticle (a protein-covered outer layer that covers the surface of the egg and fills the pores that allow air inside for the growing chick). The researcher also detected small minerals made of calcium phosphate which are typically found among birds who bury their eggs. Previous evidence suggested that Enantiornithes buried their eggs, and these latest findings add more weight to this assumption.

At the same time, this particular eggshell features some unusual characteristics. The shell is too thin and it looks like it had two layers instead of one. This suggests that the mother bird went through egg-binding — when an egg takes longer than usual to pass out of the reproductive tract — and this may have been what ultimately killed her.

The analysis also showed that Avimaia schweitzerae had a reproductive tissue called the medullary bone, making it the only Mesozoic fossil featuring this kind of structure. Previously, scientists had argued that this tissue should to be present in other fossil birds, as well as dinosaurs and pterosaurs, but until now this identification proved ambiguous.

The findings appeared in the journal Nature Communications.

Scientists show how plants communicate — and it looks amazing

Image credits: Simon Gilroy.

For a while now, researchers have been observing an intriguing phenomenon: when one part of a plant is under attack (say, by a hungry caterpillar), the defense systems are activated in other parts of the plant. But how do they know to do so? A new study sheds new light on that process, highlighting the impressive means through which plants communicate — and they have the amazing videos to go with it.

Plants don’t have nerves, but, as it turns out, they have something that’s surprisingly similar: a network of signaling cues, the same cues that many animals use in their own nervous systems.

“We know there’s this systemic signaling system, and if you wound in one place the rest of the plant triggers its defense responses. But we didn’t know what was behind this system,” explained botanist Simon Gilroy from the University of Wisconsin-Madison.

Gilroy and botanist Masatsugu Toyota, a former postdoc in Gilroy’s lab, wanted to see how this signal propagates.

“We do know that if you wound a leaf, you get an electrical charge, and you get a propagation that moves across the plant,” Gilroy adds. What triggered that electric charge, and how it moved throughout the plant, were unknown. But there was one likely culprit: calcium.

Calcium is found almost everywhere in cells, often acting in a sensor-like fashion. Because it carries an electrical charge, it can produce a signal about a changing environment. But the problem is that calcium is very difficult to study, spiking and dipping quickly, and researchers needed a way to study it in real time.

So they genetically engineered a mustard plant that would reveal changes in calcium concentration in real-time. The thus-developed plants produce a protein that fluoresces around calcium — basically, whenever there’s a spike in calcium, the plant lights up. They found that this allowed them to see the signaling process, which propagates at a speed of about 1 millimeter per second — lightning fast in the plant world, but still only a fraction of what we see in the animal world.

Toyota and Gilroy showed that when the plant is threatened (most commonly by insects) waves of calcium flow from the source of the attack throughout the plant. As soon as the defensive wave hits, defensive hormones are released in the plant in an attempt to stop the damage from taking place. These noxious hormones deter some of the plants’ predators from eating them.

The team also wanted to see what triggers this calcium release in the first place. Previous research had suggested that glutamate, an amino acid and significant neurotransmitter in both plants and animals, is the key. So they used mutant plants lacking glutamate receptors and found that the flow of calcium was also disrupted.

“Lo and behold, the mutants that knock out the electrical signaling completely knock out the calcium signaling as well,” says Gilroy.

So essentially, when the plant is bitten or attacked, it spills out glutamate from the wound site. From there, this triggers a wave of calcium flowing through the plant, which leads to activation of the plant’s hormonal defense mechanisms. It’s a remarkably complex and dynamic process, for a group of organisms which are often regarded as inert and lacking a nervous system.

In addition to the describing this process, the study videos can also help scientists visualize this astonishing mechanism — and let’s admit it, it’s also really nice to look at.

“Without the imaging and seeing it all play out in front of you, it never really got driven home — man, this stuff is fast!” he says.

The study has been published in the journal Science.


Kidney stones form like any rock, may hold day-by-day history of your body’s health

Kidney stones are actual stones, in the geologic sense of the word, new research reveals.


Fluorescence micrograph of a human kidney stone.
Image credits Mayandi Sivaguru et al., 2018, Nature.

The combined efforts of an interdisciplinary team — which included a geologist, a microscopist, and a medical doctor — revealed a surprising trait of kidney stones. These lumps of matter, traditionally believed to be homogenous elements, actually form layer-by-layer, just like any other natural or artificial mineralization.

More crucially, however, the team reports that kidney stones partially dissolve and regrow throughout their lifetime — a discovery that may unlock new, noninvasive treatments for these hurtful pebbles.

Kidney stones don’t break your bones

Kidney stones are built up from calcium-rich layers that bear a striking resemblance to other mineralizations in nature, such as those forming coral reefs, Roman aqueducts, stalactites or stalagmites, structures associated with hot springs, or subsurface oil fields, the team reports. This goes directly against the common-held wisdom that kidney stones are unique among all other rocks in nature, being homogenous and never dissolving.

“Contrary to what doctors learn in their medical training, we found that kidney stones undergo a dynamic process of growing and dissolving, growing and dissolving,” explains University of Illinois geology and microbiology professor Bruce Fouke, co-lead researcher of the paper.

“This means that one day we may be able to intervene to fully dissolve the stones right in the patient’s kidney, something most doctors today would say is impossible.”

The team’s findings were made possible by new imaging technology. This allowed the authors to look at the stones in better detail than ever before, and also employ a wider array of light- and electron-based microscopy for the task. To give you an idea of how extensive the microscopy effort was as part of this research, the methods applied by the team included: bright-field, phase-contrast, polarization, confocal, fluorescence and electron microscopy, several combinations of these methods, topped off with X-ray spectroscopy.

What’s really exciting to me personally, given my background in geophysics, is that many of these imaging techniques are traditionally the domain of geology and other earth sciences. While common-place in such fields, they haven’t really been used to study mineralizations in living organisms, such as kidney- or gallstones, Fouke remarks.

The team’s use of ultraviolet light during imaging was also particularly helpful, he adds, as the technique makes certain minerals or proteins fluoresce at the right wavelengths — allowing for quick and accurate identification of these elements under the microscope. A relatively new technology, Airyscan super-resolution microscopy, also allowed the team to snap some incredible, 140-nanometer resolution shots of the kidney stones’ structures:

Kidney stones microscopy.

COD= calcium oxalate dihydrate; COM= calcium oxalate monohydrate; UA= uric acid; HSE= historic sequence of events.
Image credits Mayandi Sivaguru et al., 2018, Nature.

“Instead of being worthless crystalline lumps, kidney stones are a minute-by-minute record of the health and functioning of a person’s kidney,” Fouke explains.

The images reveal that kidney stones start out as tiny crystals of calcium oxalate dihydrate, a mineral known as Weddellite. These crystals may lose some water, depending on conditions in the body, transitioning into calcium oxalate monohydrate (mineral Whewellite). And yes, they do sound a bit like Pokemon names.

In the early phases of kidney stone formation, these crystals bind together into irregular clumps. Organic matter and other mineral species later cake onto this core in successive layers, creating an outer shell. The process is very well known to geologists.

The presence of these layers also allowed the team to recreate the developmental history of the kidney stone, just like you would with a geological structure. Gaps in these layers point to certain parts of the stones — usually the interior dihydrate crystals — having dissolved in the past, the team reports. These gaps were subsequently filled, usually by calcium oxalate monohydrate crystals.

Kidney stone formation.

Image credits Mayandi Sivaguru et al., 2018, Nature.

“In geology, when you see layers, that means that something older is underneath something younger,” Fouke said. “One layer may be deposited over the course of very short to very long periods of time.”

“Therefore, just one rock represents a whole series of events over time that are critical to deciphering the history of kidney stone disease,” Fouke said.

The research shows that, far from being a single lump of stable crystal, kidney stones are actually a hodge-podge of whatever minerals and organic substances happened to trail along the kidney during the stone’s lifetime. They are also very dynamic, evolving continuously, potentially encasing a history of the body’s going-ons over time.

“Given these rough estimates, each nano-layer may have formed on a sub-daily basis of hours or in some cases even minutes,” the paper reads.

“If correct, kidney stones could be ‘read’ in the future under clinical conditions as an unprecedented ultrahigh-sensitivity record of in vivo human renal function and dynamic biogeochemical reactions.”

The paper “Geobiology reveals how human kidney stones dissolve in vivo” has been published in the journal Nature.

This diamond contains the first evidence of calcium silicate perovskite found in nature. Credit: Nester Korolev, UBC.

Tiny diamond provides first evidence of Earth’s fourth most abundant mineral

This diamond contains the first evidence of calcium silicate perovskite found in nature. Credit: Nester Korolev, UBC.

This diamond contains the first evidence of calcium silicate perovskite found in nature. Credit: Nester Korolev, UBC.

Calcium silicate perovskite (CaSiO3) is widely regarded as the fourth most abundant mineral on Earth but it was only recently that people were able to actually see it intact. That’s because the mineral is thought to form deep inside Earth’s mantle, an area below the planet’s surface, but above the planet’s core. Only after it made its way to the surface, trapped inside a diamond recovered from a South African mine, did we get confirmation that this mineral even exists in a stable form. As such, it provides valuable insight into the processes that govern Earth’s interior.

First time found in nature

“Nobody has ever managed to keep this mineral stable at the Earth’s surface,” said Graham Pearson, a professor in the University of Alberta’s Department of Earth and Atmospheric Sciences, in a statement.

“The only possible way of preserving this mineral at the Earth’s surface is when it’s trapped in an unyielding container like a diamond,” he explained. “Based on our findings, there could be as much as zetta tonnes (1021) of this perovskite in deep Earth.”

The lucky diamond was excavated from South Africa’s Cullinan mine, where incidentally the world’s largest diamond was also found back in 1905. This goes to show that Cullinan is not only a source for material riches but also scientifically valuable, as it provides insights into Earth’s deep core.

“Being the dominant host for calcium and, owing to its accommodating crystal structure, the major sink for heat-producing elements (potassium, uranium and thorium) in the transition zone and lower mantle, it is critical to establish its presence,” the authors wrote in the journal Nature. 

Most diamonds form 150 to 200 km below Earth’s surface, but Pearson says the perovskite-containing diamond likely formed some 700 km (435 miles) deep. The scientist thinks the diamond must have sustained 24 billion pascals of pressure — or 240,000 more than the average at sea level.

This important discovery once again highlights diamonds’ important role in preserving material and revealing clues about some of the most mysterious geological processes. The calcium silicate perovskite inclusion — perhaps the first intact sample of this material that we know of — was confirmed with X-ray and spectroscopy tests.

“Diamonds are really unique ways of seeing what’s in the Earth,” Pearson said. “And the specific composition of the perovskite inclusion in this particular diamond very clearly indicates the recycling of oceanic crust into Earth’s lower mantle. It provides fundamental proof of what happens to the fate of oceanic plates as they descend into the depths of the Earth.”

Previously, in 2014, Pearson was behind another milestone discovery which found the first evidence of ringwoodite — Earth’s fifth most abundant mineral — in another diamond.

Scientific reference: F. Nestola et al, CaSiO3 perovskite in diamond indicates the recycling of oceanic crust into the lower mantle, Nature (2018). DOI: 10.1038/nature25972.

Atom-by-atom chart of living fossil’s shell could hold the key to understanding past climate

American researchers adapted two nano-scale investigation techniques traditionally used in material sciences to take an atom by atom look at how foraminifera build their shells. The advance not only provides insight into the process of biomineralization, but will also allow us to better track the environmental history of the Earth.

Orbulina universa.
Image credits Howard Spero / UC Davis.

The team of researchers from University of California, Davis, University of Washington, and the U.S. Department of Energy’s Pacific Northwest National Laboratory developed a novel way of studying the growth patterns of foraminifera (“forams”), a type of plankton. The team created an organic-mineral interface where they could observe how calcium carbonate crystals grow in the shells.

They used two cutting-edge techniques to perform their examination: Time-of-FLight Secondary Ionization Mass Spectrometry (ToF-SIMS) and Laser-Assisted Atom Probe Tomography (APT). ToF-SIMS creates a two-dimensional chemical map of a sample’s polished surface. It was first used to perform elemental analysis of complex polymers, but it’s now finding its way to applications on natural shells. APT was first developed to analyze internal structures of alloys, silicon chips, and superconductors and results in a three-dimensional chemical map.

With these methods, the team zoomed in down to the atomic level to understand how trace impurities find their way into shells during the growth process — or biomineralization. They focused on a critical stage of the process — the interaction between the shell’s biological template and the initiation of growth.

“We’ve gotten the first glimpse of the biological event horizon,” said Howard Spero, a study co-author and UC Davis geochemistry professor.

From their observations, the team created an atomic-scale map of the chemistry taking place at this key point in time for Orbulina universa forams. This is the first ever chemical record of a calcium carbonate biomineralization template. Some surprising findings were higher-than-expected levels of sodium and magnesium in the organic material. These two elements weren’t considered as important for the overall architecture of the shells, said lead study author Oscar Branson. The finding means we can better account for these two elements when investigating paleoclimate from foram shells.

Why does that even matter?

Well, together with ice core samples, foram shells are the only medium we have that records climate conditions throughout the Earth’s past. They’ve been around for some 200 million years (surviving even asteroid impacts), raining down layers of shells on the ocean floor when they die. As the shells grow, they absorb minerals from the surrounding seawater, such as calcium, magnesium, sodium, so on. How much of each is available in the water, and how much of each is absorbed, depends directly on environmental conditions. The warmer the water was where the shell grew, the more magnesium it will contain, for example.

So by analyzing the shells’ chemical makeup, we can determine how climate conditions changed over this 200m years period.

“Finding out how much magnesium there is in a shell can allow us to find out the temperature of seawater going back up to 150 million years,” Branson said.

But each shell is composed of countless nanometer-scale bands — similar to how trees have growth rings. Element concentrations vary between these bands as well, not just between shells.

“We know that shell formation processes are important for shell chemistry, but we don’t know much about these processes or how they might have changed through time,” he said. “This adds considerable uncertainty to climate reconstructions.”

The new findings will hopefully allow us to better tune our investigations in the future, so we can create more accurate climate records of the past.

The full paper “Atom-by-atom growth chart for shells helps decode past climate” has been published in the journal Nature.


Neither vitamin D3 or calcium were found to aid respiratory illnesses. Photo credit: my.opera.com

Vitamin D and calcium supplements don’t ease winter coughs, study finds

To improve health and ease drowsy coughs during winter time, you’ll find that some sources, including physicians, advise that you add supplements to your diet in order to boost your immune system. A team of researchers report, however, after performing a randomized study that taking vitamin D, calcium or both altogether doesn’t offer any significant respiratory improvement.

Neither vitamin D3 or calcium were found to aid respiratory illnesses. Photo credit: my.opera.com

Neither vitamin D3 or calcium were found to aid respiratory illnesses. Photo credit: my.opera.com

The scientists sought to see if there was any connection between taking vitamin D   and upper respiratory tract infection (URTI). In order to become relevant, the researchers chose to survey 2259 trial participants, of general health,  aged 45–75 who were administered  vitamin D3 (1000 IU/day), calcium (1200 mg/day), both, or placebo. Of these, 759 participants completed daily symptom diaries throughout the duration of the four-year long study.

[RELATED] Four causes of winter blues and what can you do about them

During winters, those who took vitamin D experienced on average 1.8 days of respiratory-related illness, versus  1.6 days among the placebo group, an insignificant difference by the authors’ account. Regarding the calcium supplements, there was no observable difference  either. It was not associated with the incidence, duration or severity of symptoms, and was equally ineffective when taken with vitamin D.

“Of course there are observational studies that show that vitamin D has various benefits,” said the lead author, Judy R. Rees, an assistant professor of community and family medicine at Dartmouth. “But those studies can’t eliminate the effects of lifestyle from causing bias. A randomized trial is designed to avoid those problems, and that’s what I think we did.”

These results were reported in a paper published in the journal Clinical Infectious Diseases,

Alright, so it’s not the best news for those already having to deal with mid-winter coughs. Here are some tips you may want to consider though: stay well hydrated (8 glasses of water per day), be sure to get plenty of sunlight exposure (I know it’s cold outside, but at least be sure to keep your window shutters open), avoid eating sugary foods as much as possible, add honey and lemon to a glass of water and sip throughout the day and, of course, be sure to consult with your local physician.


Shorties: Adding more calcium to your diet won’t reduce fracture risk

The benefits of calcium in your diet are numerous, but according to a study conducted by University of Sweden researchers. Their study concludes that increasing calcium intake beyond a moderate amount does little to nothing in preventing osteoporosis later in life, or reduce fracture risk.

The study, published online Tuesday on the British Medical Journal website, intended to shed some light on the long standing debate of how much calcium is enough. They found that increasing consumption beyond 700 mg – equivalent to 3 oz (85 g) of sardines, bones-in and and an 8 oz pot (227 g) of yogurt has a negligible impact.