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You Asked: Does the Magnetic Laundry System work?

question markMagnets are fascinating. Imagine the amazement of the ancient Greeks who discovered that some naturally occurring stones, later named magnetite because they were found in a region of Greece called Magnesia, attracted iron. The stones also quickly attracted superstitious beliefs. Magnetite was said to have had magical powers, the ability to heal the sick and frighten away evil spirits. Archimedes, in an undoubtedly apocryphal story, is said to have used magnetite to remove nails from enemy ships and sink them. Magnets never sank ships, but they were used to guide them. We are talking about the compass.

Thousands of years ago the Chinese also noted the properties of naturally occurring magnetite. When made into the shape of a needle and floated on water, the magnetite always lined up in a north south direction! By about 1000 AD, the Chinese had developed the compass that became the key to navigation. But magnets have also been used to navigate people away from reality. In the 1800s physician Anton Mesmer had people hold onto magnetized rods to attract disease out of their body. Mesmerism, as his antics came to be called, often worked. The success of the treatment had nothing to do with the magnets, rather it was based on the belief of the patient. Magnets are great placebos. Today, magnetized bracelets can be purchased to energize the gullible. And you can buy magnetic laundry disks for insertion into washing machines to allow laundry to be done without the use of detergents. The claim is that the magnets ionize water and thereby increase its cleaning ability. Nonsense.

Advertising for these products often attacks commercial detergents accusing them of containing cancer causing chemicals and hormone disruptors. The claim is that the magnetic disks reduce health risks by eliminating exposure to these substances while also saving money since there is no need to purchase detergents. Furthermore, use of the disks prevents the release of toxic substances into the environment. That all sounds very “green.” References are given to a patent for the laundry disks, as well as to a study supposedly demonstrating their cleaning efficacy.

It is important to understand that the only requirement for obtaining a patent is novelty. In this case, since nobody before had the idea of putting magnets into a washing machine, the patent was not hard to get. When it comes to the patent, there is no need to show that the magnets actually do anything, just that their use in this context is novel. How about the study carried out by a testing lab that examined the cleaning efficacy? Technicians actually took bundles of clothes, washed them in a magnet equipped washing machine and demonstrated they came out cleaner than they went in. Surprise, surprise! Water is an excellent solvent and cleans remarkably well even without any detergent. The “study” had no control. That is, there was no comparison between laundering with just water and laundering with the magnetized water.

Is there any rationale that the magnets can actually do something? Water is diamagnetic, which means that it will be repelled by a magnet. But the effect is very, very, small. If a vial of water is placed on a piece of floating Styrofoam and a strong magnet is brought close, it will slowly move away from the magnet. An interesting phenomenon, but nothing to do with cleaning ability. But there is something about the advertising for the laundry disks that is not contestable. They are guaranteed to last for fifty years, a guarantee that is indeed safe since magnets do not rot. That is more than what can be said about the claims of their miraculous cleaning properties.

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DEET Me Up: How Best to Repel a Mosquito


When it comes to protection from mosquitoes, opinions are abuzz.  Burn citronella candles.  Wear repellant bracelets.  Douse yourself with Avon’s Skin-So-Soft.  Eat garlic.  Take vitamin B1 supplements.  Use concentrated DEET.  Use dilute DEET.  People are confused.  Needlessly.  There are many questions science cannot readily answer, but the question of what is the most effective mosquito repellant is not one of them.  That’s because it doesn’t take rocket science to design an appropriate study.  You don’t need sophisticated equipment and you don’t have to extrapolate from rat studies.  All you need are some human volunteers who are willing to stick their bare arms into a cage of hungry female mosquitoes.  And that is exactly what researchers had fifteen volunteers do at the University of Florida in a study reported in the New England Journal of Medicine.  And now we know what works and what does not.

This study was very carefully done.  Temperature, humidity, density of the mosquito population and state of hunger of the insects were all controlled.  Sixteen popular products were purchased and tested repeatedly with the time until first bite being accurately measured.  Lets’ start with what doesn’t work.  You can forget about any of the “repellant” wristbands.  They kept mosquitoes away for the stunning time of about twenty seconds.  Avon’s “Skin-So-Soft” may make your skin feel soft but will only keep the bugs away for about twenty minutes.  After that your skin will get pretty bumpy from all the bites. Other citronella preparations fared even worse.  So unless you are willing to walk around constantly spraying yourself, forget the citronella products.  So what works?  N,N-diethyl-m-toluamide or “DEET.”

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Chaotic Seabirds
In August 1961, in Capitola and Santa Cruz, California there was an invasion of what people described as “chaotic seabirds.” These birds were believed to be under the influence of domoic acid, a neurotoxin that is produced by algae and accumulates in shellfish, sardines, and anchovies (aka “filter feeders”) and inspired a scene in Alfred Hitchcock’s feature 1963 film, “The Birds.”

Same Genes, Different Traits
Even though identical (monozygotic) twins may have the exact same gentic make-up, it is possible that they can have different features from one another. This is thanks to differences in the womb (also known as “developmental noise”, where indivudals can develop differences due to noise in signaling and signal interpretation) and differences in environments ancountered after birth. In fact, the genes – albeit identical – can actually be expressed differently, thereby leading to very different drug reactions and susceptibilities to disease. This is one reason why one identical twin may suffer from a disease like Multiple Sclerosis while the other does not.

A Vegas Myth
I’m sure you’ve heard the myth that oxygen is pumped into casinos to give people more energy and keep them awake. This is, in fact, the enduring Vegas myth of all time. There’s no doubt that the casinos keep the air chilly to give that same effect, but there’s no mechanim actually pumping extra oxygen into the system. If this were to be true, a major problem could ensue – since pumping oxygen into a room would increase the flammability of the air.

Babies, C-Sections & Microbes
Babies who are delivered by C-section don’t go through the birth canal, and as a result they don’t get the beneficial microbes that babies born via the birth canal receive. This might help explain why C-section babies are at a higher risk for a variety of diseases. A recent study suggests, however, that this can be mitigated by slathering babies just after birth with a gauze pad that soaked up the microbes in the mothers’ birth canal right before birth. Why? Because it helps restore and normalize the baby’s microbiome.

It Ain’t Over Till The Fat Lady Sings…or is it?
There seems to be a longstanding relationship between the opera and weight. Famous operatic tenor and pasta lover, Luciano Pavarotti, was estimated to have gained and lost more than five thousand pounds in his career and theorized that fat people were happy because their nerves were “well protected.” And then there’s the expression, “it ain’t over until the fat lady sings”, which in today’s day may be no longer applicable. A few years ago, Deborah Voigt, an American soprano, was fired at London’s Covent Garden for being too large to fit into the cocktail dress designed for her character in Strauss’s opera, Ariadne auf Naxos. Voigt later underwent gastric bypass surgery and was then rehired for the same role at the same venue.  Read more

Toxic chemicals in the environment

photosynthesisVirtually no day goes by without an alert from the media about some chemical in the environment that is suspected of harming our health. It may do this by disrupting our hormones, triggering cancer, causing heart disease, affecting brain development, or any combination of these. Among numerous other substances it might be oxybenzone in sunscreens, tetrachloroethylene residue in dry cleaned clothes, caramel colouring in cola drinks, arsenic in rice or phthalates in plastics. The allegations are generally backed up by references to the scientific literature but interpreting the data in practical terms is very challenging. It has been said that our ability to collect data has outstripped our ability to analyze what the data means.

Take endocrine disruptors for example. These are chemicals that can in some way interfere with the chemical messengers we call hormones. Such interference can cause cancer, developmental issues, learning disabilities, attention deficit disorder, obesity and reproduction problems, especially if exposure is during the critical period of development between a fertilized egg and a full formed baby. This is the time when cells multiply quickly and take on their individual characteristics. Exposure to chemicals that would be innocuous in an adult can at this point have serious consequences. It stands to reason that effort should be made to reduce exposure to endocrine disruptors particularly during pregnancy.

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plastic bottles“I hate plastics. We should get rid of them.” So began an email I received. The correspondent went on to talk about how plastics are a plague on the environment, how they contain chemicals that contaminate our food supply, disrupt our hormones, cause autism and ADHD and use up valuable petroleum deposits. What prompted the email was some comments I made about different plastics having different properties and how there were some concerns with some but not with others. The disturbing part of the message was the insinuation that I must be in the pockets of the plastic industry since I did not agree that plastics were substances forged in hell. That allegation is easy to answer. I get zero funding from the petroleum or plastics industries. My allegiance is to the scientific method. Where that path leads, I go.

It is true that plastics can be an environmental plague. But plastic shopping bags don’t jump into rivers or trees by themselves, and empty bottles that should be recycled don’t leap into garbage cans unaided. People are the problem. As far as using up petroleum resources, only about 5% of oil goes towards plastic manufacture, and in North America the prime raw material is actually not petroleum but natural gas. I should add that while plastics are mostly made from fossil fuels, this is not the case exclusively. Polylactic acid, widely used today, is made from corn and there is extensive research in the area of “green chemistry” to produce a variety of polymers from plant products.

What about the bit about contamination of our food supply? Anytime two surfaces come into contact, there is an exchange of chemicals. Indeed, it is possible that trace amounts of plastic chemicals with endocrine disruptive properties may end up in our food supply, but the dose is so small that any sort of harmful effect is very unlikely. Heat increases the release of chemicals, so it is better to use glass or ceramic for warming up food, although plastics labeled as microwave safe contain no easily leached components. As far as ADHD and autism go, the fact is that nobody knows the cause. There is much speculation ranging from genetics and microbiome imbalances to environmental contaminants but plastic ingredients would come way down the list. It is true that we can definitely live without plastic microbeads in cosmetics and even without synthetic fabrics, although resorting to cotton poses a whole range of other problems. But the suggestion to get rid of plastics is simple-minded nonsense that amounts to lack of seeing the forest for the trees.

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You Asked: Is it true that getting angry can affect the heart?

stressAccording to a study in the European Heart Journal, a single angry outburst can have immediate adverse effects. That’s because anger causes an increase in blood pressure and a release of the stress hormones adrenaline and cortisol. Indeed, the risk of a heart attack or angina is nearly five times higher in the two hours following an anger outburst than at other times, and the risk of stroke is four times higher. Let’s not get too carried away with this though, because at any given moment the risk of a heart attack or stroke is very low, so even a five fold increase in risk isn’t that great. To put the numbers into perspective, researchers estimate that if 10,000 healthy people have one anger outburst a month over a year, one of them will suffer a heart attack or a stroke as a result of the outburst. Among people who have other risk factors such as smoking, being overweight, high blood pressure or high cholesterol, there would be four cardiovascular events over a year with one monthly outburst. But among people who get angry more often, which is not an unusual scenario, the risk rises significantly. For example, if 10,000 people who also have other risk factors have five angry outbursts a day, some 600 of them will have a heart attack or stroke.

Small beads can make for a large problem

dangerScience can make for a strange bedfellow. I had just finished recording a video showing off one of my favourite sweaters and expounding on the ingenuity and the environmental benefit of it being made from recycled polyester bottles when an article appeared on one of my newsfeeds about how “your clothes are poisoning our oceans and food supply.” The message was that the very fabric I was so high on may be unravelling the fabric of society.

I must say I was puzzled by the headline, but on glancing through the story, the details of the problem quickly came out in the wash, as it were. Synthetic fabrics are not exactly inert and release microscopic bits of fiber when washed. The particles may be microscopic, but their number is anything but. Researchers at the University of California found that a synthetic fleece jacket releases hundreds of thousands of microscopic fibers, about 2 grams in total, with each wash. Wastewater treatment removes some of this debris, but most of it ends up in rivers, lakes and oceans where it can be consumed by wildlife. The fibers then can bioaccumulate up the aquatic food chain, right up to people consuming fish. Whether this presents a risk is not known, but bits of plastic are not a desirable dietary component. The clothing industry is sensitive to the problem and is working on coatings for fabric that would reduce shedding. Also in the works are washing machines that prevent the release of microfibers by using pressurized carbon dioxide instead of water.

The shedding of microfibers from synthetic fabrics is not the only way tiny pieces of plastic, invisible to the naked eye, end up in water systems.” Microbeads,” introduced into consumer products such as toothpaste and exfoliating skin products as abrasives, are a bigger concern. Six varieties of the tiny beads are used. Those composed of either polyethylene, polypropylene or expanded polystyrene are more likely to float, whereas the ones made of polyvinyl chloride, nylon or polyethylene terephthalate (PET) are more likely to sink. McGill biologist Anthony Ricciardi has found microbeads in significant numbers in sediment at the bottom of the St. Lawrence River, meaning possible contamination of fish that feed on the riverbed.

Microbeads range in size from 10 millionths of a meter to one millimeter. Their round shape makes them much less irritating than irregularly shaped, abrasive exfoliants like apricot kernels or walnut shells that have sharp edges. Also, because the particles are tiny spheres, they act as little ball bearings, allowing for easy spreadability of creams and lotions as well as a smooth texture and silky feel. There’s more. Imperfections in the skin tend to be visible because of the contrast between how they reflect light compared with the surrounding tissue. Microbeads with their ability to scatter and diffuse light can minimize the appearance of fine lines and improve skin tone. When it comes to toothpaste, though, they make a minimal contribution to polishing the teeth and may actually become embedded in gum tissue. Why are they there? Since the microbeads can be produced in various colours they can also increase the visual appeal of a product.

A single container of face wash can contain hundreds of thousands of the microspheres. While the virtually indestructible plastic beads are not themselves toxic, once they enter the water, they attract potentially toxic substances such as PCBs, triclosan and nonylphenols. Like the microfibers, microbeads can then become part of the aquatic food chain, eaten by fish and then by people. Once consumed, the beads may also leach out plastic additives like colourants, plasticizers and ultraviolet light stabilizers.

Researchers have found fish both in the oceans and the Great Lakes contaminated with microbeads. Besides carrying toxins, the beads can cause internal abrasions and can stunt growth of the fish by giving them a false sense of being full. One-third of fish caught off the south-west coast of England have been found to contain microbeads and  Belgian researchers studying seafood from German farms and French supermarkets found that an average portion of mussels can contain about ninety microplastic particles, and an order of oysters about fifty. The beads have also been found to lodge in the guts of crabs as well as in their gills.

The number of microbeads that end up in the environment is staggering. In New York State alone some 19 tons go down the drain every year. Most wastewater plants are not equipped to filter out such fine particles and while they could be retrofitted, the expense would be prohibitive. Drinking water poses less of a problem because municipal water treatment plants can filter out the tiny particles although a sampling of German beers found microbeads in every bottle, with the water used being the likely source. Both Canada and the U.S. have moved to ban microbeads and manufacturers have started the process of phasing them out. Researchers agree that there are still too many unknowns to fully assess the environmental damage caused by microplastics but given that they do not contribute significant benefits they should be eliminated.

But the problem of plastic waste in the oceans is greater than can be accounted for by microfibers and microbeads. Other tiny particles form from the breakdown of plastic bags, bottles and all sorts of containers that get discarded end up in waste streams that empty into the ocean. “Biodegradable” on a label means that the plastic has been shown to degrade under ideal composting conditions, but these do not exist in the natural environment. Estimates are that the ratio of plastics to fish by weight in the oceans is 1:5 and with our current callous attitude towards “reduce, recycle, reuse,” it is set to increase to 1:1 by 2050.

Given these concerns, I don’t think I can wear my “made from a plastic bottle” sweater with the same pride as before. And I may even feel a bit of apprehension tossing it into the laundry basket.


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Vitamin D and Prevention of Disease

vitamin DTo take or not to take, that is the question many people have been asking themselves about vitamin D supplements. As is so often the case in science, there is no concrete answer. This in spite of close to 2000 studies published in the scientific literature. What that means is that if an effect exists, it is likely to be small, because if it were significant it would have revealed itself.

There is no question that a deficiency of vitamin D is responsible for rickets and that vitamin D supplements can help. But beyond that, the situation is quite murky. Given that rickets is a bone weakness problem, it is reasonable to explore whether vitamin D supplements can protect against fractures, particularly among the elderly. There are consistent observational studies showing an association between low vitamin D levels in the blood and greater risk of fractures. However, studies on supplementing the diet with vitamin D have not shown spectacular results. When the studies dealing with fractures are pooled, the evidence that emerges is that taking roughly 1000 IU of vitamin D and 500 mg of calcium can have an effect on fracture reduction, but not a very significant one. The data indicate that roughly fifty people would have to take vitamin D and calcium every day for ten years to prevent one fracture. There is no increased advantage to taking more than 1000 IU a day.

Vitamin D supplements have also been claimed to be of help in multiple sclerosis, depression, rheumatoid arthritis and respiratory tract infections. In the case of MS, it is well known that the incidence increases with latitude, suggesting that decreased exposure to ultraviolet light leading to a reduced formation of vitamin D in the body may play a role. But supplementation with vitamin D has not been shown to have a clinical effect. Neither has benefit been shown for depression or respiratory tract infections.

There has also been much interest in exploring the potential of vitamin D supplements in preventing cancer given that observational studies have consistently shown that people with low blood levels of the vitamin have a greater risk of cancer, especially of the breast. But the question here is whether low levels predispose to cancer, or whether cancer causes vitamin D levels to drop. A few studies, mostly in women, have shown that supplements reduce the incidence of cancer but in general the total number of cancer cases in these trials is too small for sweeping generalizations. Nevertheless, the trend in the cancer studies is towards showing at least a minor protective effect with vitamin D. So, the bottom line is that vitamin D is no panacea, but may play a small role in preventing fractures and possibly some cancers. Given that there is no recorded downside to dosing with 1000 IU a day, and that the supplement is cheap, it seems that taking a 1000 IU vitamin D supplement is not unreasonable, especially for women. The potential benefit is very small, but the risk is essentially zero.

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