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Charcoal is one of the most important substances ever discovered

charcoalIt’s a killer. It’s a saviour. It’s also a trickster. It’s one of the most important substances ever discovered. It’s charcoal!

Burn any animal or vegetable matter with a limited supply of air, as is the case inside a wood pile, and you are left with charcoal, essentially carbon mixed with some mineral ash. The fact that charcoal burns better than wood was probably noted soon after man learned to control fire over a million years ago. The first use of charcoal for purposes other than providing heat was around 30,000 BC when cavemen used it as a pigment for drawing on the walls of caves.

Then around 4000 BC came a monumental discovery, probably by accident, when a piece of ore fell into a charcoal fire and began to ooze metal. When naturally occurring ores of copper, zinc and tin oxides are heated with charcoal, the carbon strips away the oxygen, leaving the pure metal behind. Alloying copper with tin forms bronze. The Bronze Age was followed by the Iron Age, characterized by the smelting of iron from iron oxide with charcoal. That same technology is still used today. But it wasn’t only through the smelting of metals that charcoal had an impact on history.

Sometime in the 9th century a Chinese alchemist discovered that blending charcoal with saltpeter (potassium nitrate) and sulphur resulted in a mixture that would combust readily. “Gunpowder” would eventually be used to create explosives that gave access to coal and minerals, making huge engineering achievements possible. Of course gunpowder also made possible the easier destruction of life, casting a dark shadow on charcoal.

Around 1500 BC, Egyptian papyri recorded the use of charcoal to eliminate bad smells from wounds, the first mention of a medical application of charcoal. By 400 BC, the Phoenicians were storing water in charred barrels on trading ships to improve its taste. It seems they had hit upon one of charcoal’s most important properties, the ability to bind substances to its surface, a phenomenon known as “adsorption.” That application lay more or less dormant until the late 18th century, when Europeans developed a taste for sugar. Raw sugar from sugar cane or sugar beets is tainted by coloured impurities that can be removed by passing sugar extract through beds of charcoal.

The rapid growth of the sugar refining industry led to a search for charcoal with improved adsorption properties and resulted in the development of “activated” charcoal, also referred to as “activated carbon.” In this process, carbonaceous matter such as wood, coal or nutshells is first heated in the absence of air, followed by exposure to carbon dioxide, oxygen or steam. This has the effect of increasing the surface area and establishing a network of submicroscopic pores where adsorption takes place. Later, it was determined that impregnation with chemicals like zinc chloride or phosphoric acid prior to heating improved the adsorption properties. Today, a variety of activated carbon products are available for use in various applications.

Activated charcoal is used in water filters, air purification systems, gas masks and even underwear. Yes, flatulence filtering undergarment for people suffering from various gastric problems really works. But in order to avoid flatulence escaping around the filter, the patient is recommended to stand with legs together and let the wind out slowly.

Because of its amazing adsorptive properties, activated carbon is a staple in emergency rooms. In cases of suspected drug overdose or poisoning, it is administered orally to bind the toxins before they have a chance to be absorbed into the bloodstream. It isn’t surprising that inventive marketers have absorbed this information and have started to roll out various foods and beverages containing activated carbon with promises of “detoxing.” “Black Magic Activated Charcoal” a “zesty lemon detox and purification elixir,” invites you to “come over to the dark side.” A very apropos invitation. Just what sorts of toxins are this beverage supposed to remove? And since activated carbon isn’t very specific in what it adsorbs, it is as likely to remove vitamins, polyphenols and medications as those unnamed toxins. Of course it is made with “alkaline water,” catering to the nonsense that cancer is caused by an acidic pH. Any alkaline water is of course immediately neutralized by stomach acid. Believe it or not, you can also get “activated carbon ramen noodles.” The only thing these will eliminate is your appetite.

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Food Babe Lesson #2

vani hariI’m not sure my chemistry lesson for the Food Babe got through to her but many of you said that I should keep up the effort to teach her some science. Others said that it was like trying to teach an ant to crawl up a Teflon wall. Let’s give it another shot.

Vani, you posted a recipe for a smoothie, which is fine, but it was accompanied by this introduction:

“I include smoothie recipes like this as a regular part of this program because it’s one of the best ways to get greens in your diet, provide your body a rich source of chlorophyll on a daily basis, and ultimately is one of the key actions you can take to keep your body in an alkaline state to avoid disease!”

Chlorophyll is one of the most important compounds in the world because without it plants cannot photosynthesize and without plants there is no life. But humans are not plants; we do not photosynthesize and have no need for chlorophyll. Yes, there are some claims that chlorophyll in the diet can prevent some carcinogens, such as produced by high cooking temperatures, but there is no proper scientific evidence that this is so. But that is a minor point in comparison to your call for keeping the body in an alkaline state.

Alkalizing” the body is a nonsensical concept. The human body carefully maintains the pH of blood at about 7.35, which is slightly alkaline, or basic. This is also the pH of the cells in all our organs that depend on the blood supply for their nourishment. Should the pH drop below 7 or exceed 7.7 we are looking at a potentially catastrophic situation. Luckily, our blood constitutes a buffered system, meaning that any variation of pH is immediately compensated for. Should there be an increase in acids entering the bloodstream, we immediately start exhaling more carbon dioxide, which then reduces acidity. Should the blood start to alkalize, the lungs retain more carbon dioxide, which dissolves to form carbonic acid while the kidneys eliminate basic bicarbonate.

What all this means is that the pH of the blood cannot be altered by changing the diet. A change in diet can certainly alter the acidity of the urine but that is unrelated to the pH of the blood. Breads, cereals, eggs, fish, meat, poultry can acidify the urine while most fruits and vegetables tend to make it more alkaline. The idea of monitoring the pH of the urine to achieve optimal health by “balancing” the body’s acidity is senseless. Is it possible that some people feel better by making their urine more alkaline? That’s possible. If they switch from a heavy meat and cereal diet to one that features more fruits and vegetables they may feel better. But this has nothing to do with balancing the body’s pH.

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Food Babe Lesson #1

vani hariI think instead of criticizing the Food Babe on a regular basis, which could easily become a second career, it is time to take a different approach. Maybe we can be pro-active here and attempt to teach her some of the chemistry she so sorely lacks.

Vani, in your attack on polydimethylsiloxane, a chemical used to prevent foaming in frying oils, you make the following claim: “The FDA allows dimethylpolysiloxane to be preserved by several different chemicals that don’t have to be listed on the label either, including formaldehyde!”

First of all polydimethylsiloxane is a polymer (that’s a giant molecule made of repeating units) that does not require a preservative. There is no formaldehyde added to this polymer! Your confusion probably comes from having seen polydimethylsiloxane and formaldehyde appear in the same sentence somewhere. That’s because at temperatures above 200 degrees C, the methyl groups (those are groupings made of three hydrogen atoms attached to a carbon atom) on the silicone polymer react with oxygen from the air, and through a complex series of reactions can produce trace amounts of formaldehyde.

Now for some numbers..the crux of science. Polydimethylsiloxane is used at a concentration of 0.2-0.3 parts per million in commercial cooking oil. If this released the maximum amount of formaldehyde, it would be way less than the formaldehyde that occurs naturally in a glass of apple juice. But frying is done at 185-190 degrees C, and at that temperature essentially no formaldehyde is produced. Furthermore, the addition of polydimethylsiloxane to oil reduces the formation of oxidation products. I realize that there are words here you don’t understand, but maybe you get the gist of the argument. Maybe.

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“Oh… Those nasty chemicals!”

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Click here to see video.

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Catching some rays could help your heart

exposure to lightLife comes down to a struggle between risk and benefit. Although not always consciously, we evaluate our diet, our cosmetics, our medications, household chemicals and activity levels on the basis of whether they are good or bad for us. Mention sun exposure, and the conflict comes down to the “bad,” namely skin cancer, and the “good,” usually ascribed to the enhanced production of vitamin D. Skin cancer is bad, but why is vitamin D good? For one, it is required for the proper absorption of calcium and a lack can lead to soft bones, in extreme cases to the characteristic bow legs of rickets. But there may be more to vitamin D.

Epidemiological investigations have shown that people with high blood levels are generally healthier, particularly when it comes to cardiovascular disease. It is interesting to note that the heart disease rate in Australia is lower than in northern climates, and that in Britain the risk increases as one travels north even when lifestyle factors are taken in to account. But here is a curiosity. Numerous studies have been carried out with vitamin D supplements without noting an effect on cardiovascular disease. Could it be that high blood levels of vitamin D are just a marker for sun exposure and that the cardiovascular benefits are actually due to some other feature of sunlight? British dermatologist Richard Weller makes a case for nitric oxide, a chemical that can be released by the action of ultraviolet light on substances such as nitrates that are stored in the skin.

Nitric oxide is a gas, and lasts only a few seconds after it is produced in the inner lining of blood vessels by the action of enzymes on the amino acid arginine. During its brief existence, though, it acts as an important signalling molecule causing smooth muscles around blood vessels to relax. This results in an increased blood flow and a lowering of blood pressure. Indeed, the classic drug to treat angina, nitroglycerine, works by releasing nitric oxide, and Viagra’s performance is due to its ability to increase signalling and improve blood flow through the nitric oxide pathway.

It was back in 1996 that Weller discovered that sunlight had the ability to convert nitrates in the skin to nitric oxide, a discovery that took on greater meaning with the awarding of the 1998 Nobel Prize in Physiology or Medicine to Robert F. Furchgott, Louis J. Ignarro and Ferid Murad “for their discoveries concerning nitric oxide as a signalling molecule in the cardiovascular system.” Weller began to wonder whether nitric oxide produced by sun exposure might explain the lower blood pressure in populations living closer to the equator and why the average blood pressure in the U.K. is lower in summer than in winter.

To investigate, Weller exposed volunteers to ultraviolet light and measured blood pressure and nitric oxide levels. To eliminate the possibility of vitamin D playing a role, he used long wavelength UVA that does not produce vitamin D. Nitric oxide levels increased and blood pressure decreased with an exposure equivalent to about thirty minutes of sunshine in Edinburgh in the summer. The effect wasn’t dramatic, but could be significant in a large population. Just heating the skin had no effect, so UVA is needed to produce nitric oxide.

In another experiment, the performance of cyclists was enhanced in response to irradiation with UVA but only if they took nitrate supplements. The theory is that increased nitric oxide release dilates blood vessels and allows more oxygen to reach the muscles. Nitrates occur naturally, and are particularly high in celery, red beet root, lettuce and spinach, vegetables that have been associated with lower blood pressure. In light of Weller’s studies, this may be a consequence of the combination of nitrates and exposure to sunlight. He also identifies studies that showed Scandinavian women who spent more time sunbathing lived longer. Of course that may also have been due to less stress, different diets or activity levels. And then there is a Danish study that showed that people with non-melanoma skin cancer were much less likely to have a heart attack. Could skin cancer be a marker for a longer life?

As I said, life is a struggle between the good and the bad, but it isn’t easy to identify what is good and what is bad. Maybe someone should investigate if nudists live longer.

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You Asked: Why does a barber’s pole has a red stripe?

barber poleIt represents the colour of blood. During the Middle Ages monks were required to shave the crown of their head, a function commonly performed by itinerant barbers. Also, under ecclesiastic law, monks had to be periodically bled. This was supposedly a symbol of piousness, of devotion to God.
Barbers began to attend to this duty as well. They would travel with a “flag” of a white cloth dipped in blood to indicate that they would attend to anyone who needed to be bled. This early mode of advertisement eventually was transformed into the barber’s pole. And the pole began to symbolize more than haircuts and bleeding. Barbers began to expand their role and became quasi surgeons, specializing in sewing up wounds and extracting teeth. They also dabbled in the whitening of teeth by dabbing them with nitric acid. This did produce an immediate whitening, but destroyed the teeth in the long run by wearing away the protective enamel.
But at least one 16th-century barber surgeon, Ambroise Pare, made an important contribution to medicine. Barbers in those days worked under the guidance of physicians, who thought themselves above menial jobs like cutting and scalding. Why scalding? Because physicians thought that gunpowder was poisonous and therefore gunshot wounds had to be treated with boiling oil to destroy the poison. Unfortunately, if the bullet didn’t kill the victim, the scalding often did.
During the siege of Turin in 1537 Pare ran out of oil and for some reason substituted a cold mixture of egg yolks, oil of roses, and turpentine. To his surprise, the soldiers treated with this mixture fared better than those who had been scalded. And thus ended the brutal practice of pouring hot oil into bullet wounds. The French-trained Pare was a religious sort, and thought he had had help in making his observation. That’s why he introduced the oft-repeated phrase, “I dressed the wound, but God healed him.”

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A Question of Evidence

Alzheimer'sWhen we take a medication, we trust there is evidence that it will work. When we apply a cosmetic, we trust there is evidence that it is safe. When we put on a sunscreen, we trust there is evidence that it filters ultraviolet light. But evidence is not white or black; it runs the gamut from anecdotal to incontrovertible.

Some people claim that placing a bar of soap under the sheet when they sleep solves the problem of restless leg syndrome. That’s what we call anecdotal evidence, and it remains so until it is confirmed or dismissed by proper randomized double-blind controlled trials. On the other hand, evidence that gold conducts electricity is ironclad. There are no ifs or buts about it. Often, though, the use of the term “evidence” is open to interpretation. An interesting example is a recent paper published in Nature, one of the world’s foremost scientific journals, intriguingly titled: “Evidence for human transmission of amyloid-beta pathology and cerebral amyloid angiopathy.”

Let’s dissect this title. Amyloid-beta proteins are one of the hallmarks of Alzheimer’s disease, so the title implies that evidence has been found that the disease can be transmitted from person to person. Little wonder that the paper generated headlines in the lay press ranging from “Alzheimer’s may be a transmissible infection” and “You can catch Alzheimer’s” to “Alzheimer’s bombshell.” All of these are highly misleading because the paper, in spite of its provocative title, does not provide evidence for the transmission of Alzheimer’s disease between humans.

So what did the researchers, led by Dr. John Collinge of University College London, actually find? They investigated the brains of eight people who had been injected with human growth hormone as children due to stunted growth back when this hormone was extracted from the pituitary glands of dead donors. Unfortunately, the donors from whom the hormone was extracted for these children had been harbouring proteins known as “prions” that cause Creutzfeldt-Jakob disease, a terminal neurological affliction. The recipients ended up dying from the disease they had contracted via the hormone.

Collinge found that six of the eight people also had amyloid plaques typical of Alzheimer’s disease. But none of 116 people who had died of Creutzfeldt-Jakob disease who had not received contaminated growth hormone showed any sign of amyloid protein deposits. Dr. Collinge therefore suggests that molecules that lead to amyloid plaque formation were passed to the recipients along with the growth hormone.

A very interesting hypothesis to be sure. But the study did not show that the patients would actually have developed Alzheimer’s had they lived longer. A more appropriate title for the paper would have been “Possibility for human transmission of amyloid-beta pathology via contaminated growth hormone.” The word “evidence” should not have appeared in the title. The authors point out clearly that “there is no suggestion that Alzheimer’s disease is a contagious disease and no supportive evidence from epidemiological studies that Alzheimer’s disease is transmissible.” Nevertheless it was the term “evidence” that caught journalists’ eye and created undue public alarm with the suggestion that Alzheimer’s disease can be “caught.”

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Phthalates and microwave ovens

phthalateIt always pays to read the study! It really does, because popular accounts often misinterpret what researchers actually found and end up raising undue alarm. Of course it is raising the red flag of alarm that gets attention, and these days, with all sorts of bloggers scooting around to popularize their websites hoping to recruit advertisers, getting attention is what it is all about. Let’s get down to a study that generated the headline: “Don’t Microwave Those Vegetables; It Could Lead to Diabetes.” As one would expect, that headline ricocheted around the Internet spawning all sorts of comments about the evils of microwave ovens and plastic dishes. First of all, the study referred to was not about microwaving leftovers, and second, the word diabetes was never mentioned. What researches did was to take some data about phthalate metabolites found in urine as measured on a single occasion to see if there was any association with blood pressure. They did find an association, albeit a weak one. There was a difference of 1-2 mm Hg in systolic blood pressure between low and high levels of phthalate metabolites, which is essentially insignificant for an individual but could have significance across a population.
Where do the phthalates come from? These chemicals are used extensively as “plasticizers” to soften hard plastics such as polyvinyl chloride (PVC) which is commonly used in food production equipment, floor tiles, blinds, furniture and packaging. So given the ubiquitous nature of PVC, it isn’t surprising that trace amounts of phthalates end up in the urine. But microwave containers are not made of PVC; they are made of polyethylene or polypropylene which contain no phthalates. While some commercial plastic wraps are made of PVC, home plastic wraps and sandwich bags are usually made of polyethylene with no phthalates in sight.
There are other issues here too. Associations cannot prove cause and effect. Indeed, there may actually be reverse causation. People may have higher blood pressure because they eat a lot of processed foods which may harbour phthalates, but the increase in blood pressure may be due to other components such as salt or fat. Phthalates may be just a marker for processed food consumption. Furthermore, there are many kinds of phthalates and they have very different properties. Also, single measurements of substances in urine are always a problem because they may not be reflective of average values.
The bottom line here is that this study has nothing to do with microwave dishes or with diabetes. The only way any connection can be made to diabetes is through suggesting that high blood pressure can increase the risk of diabetes. But most assuredly, in spite of the headlines it generated, this study does not show that using plastics in a microwave oven could lead to diabetes.

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