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Turning White Wine into Red

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YOU ASKED: Why do we refrigerate our eggs?

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The Right Chemistry: Sugar research left a bitter taste

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“Is it true that putting a piece of garlic in the rectum at night can cleanse the body?”

And with that single question posed by an audience member back in 1975, my chemical focus shifted to food and nutrition. The question came after one of my first public talks on chemistry at a local library, where I had described the role chemistry plays in our daily lives, mostly using dyes, drugs, plastics and cosmetics as examples.

I was sort of taken aback by the question, but managed to stammer something like “where did you hear that?”

Back came the answer, “from Panic in the Pantry.” After mentioning that my only experience with garlic had been with rubbing it on toast with some very satisfying results to the palate, I promised to check out the reference.

It wasn’t hard to track down Panic in the Pantry in a local bookstore. The title had suggested some sort of attack on our food system, but this turned out not to be the case. At least not in the way I had thought. Flipping through the book I came across terms like “chemophobia,” “carcinogen,” “additives,” “chemical-free” and “health foods.” I was intrigued, especially on noting that the book had had been written by Frederick Stare, a physician with a previous degree in chemistry who had founded the Department of Nutrition at Harvard’s School of Public Health, and co-author Elizabeth Whelan. Within a day I had read Panic in the Pantry from cover to cover and was so captivated that I dove into the turbid waters of nutrition and food chemistry with great enthusiasm. Ever since then, I have been trying to keep my head above water, buffeted by the growing waves of information and misinformation.

Panic in the Pantry focused on what the authors believed were unrealistic worries about our food supply, vigorously attacking the popular lay notion that “if you can’t pronounce it, it must be harmful.” Yes, that daft message was around long before the Food Babe made it her anthem. In truth, the risks and benefits of a chemical are a consequence of its molecular structure, and are determined by appropriate studies, not by the number of syllables in its name. Stare and Whelan also challenged the “Delaney Clause,” a piece of U.S. legislation stating that no additive shall be deemed safe if it has been shown to cause cancer in any species upon any type of exposure. They pointed at studies that showed very different effects of chemicals in rodents and humans and maintained that it was unrealistic to condemn additives if exposure was not taken into account. “Too much sun can cause skin cancer, but does that mean we should stay indoors all the time?” they asked.

What about the curious case of the clove of garlic in the rectum? An excellent example of a misinterpretation of information, something that I have seen much too often. In a discussion of food faddism through the ages, the authors introduced the antics of one Adolphus Hohensee, who had forged a career as a “health food” advocate after his real estate business had landed him in jail for mail fraud. The dietary guru told his audiences that the sex act should last an hour, and if they did not measure up to this level of sexual adequacy it was because they had a diet laden with additives.

Hohensee’s answer to the chemical onslaught was a clove of garlic in the rectum at night, with proof of its efficacy being the scent of garlic on the breath in the morning. Obviously, the garlic had worked its way from bottom to top, cleansing everything in-between. Far from promoting this regimen, Stare and Whelan had used it to highlight the extent of nutritional quackery.

I found most of the arguments in Panic in the Pantry highly palatable, but there was a discussion of one chemical that left a somewhat bitter taste. That chemical was sugar. I had been quite taken by Pure, White and Deadly, a 1972 book by British physiologist John Yudkin, who made a compelling case linking sugar to heart disease, cavities, diabetes, obesity and possibly some cancers. Stare dismissed sugar as a culprit, implicating saturated fats as the cause of coronary disease. That to me seemed not to meet the standard of evidence that was applied to other issues in Panic in the Pantry.

As it turns out, there was a reason for Stare’s dismissal of sugar as a health problem. In 1965, the Sugar Research Foundation (SRF), the industry’s trade association, asked Stare to sit on its advisory board because of his expertise in the dietary causes of heart disease. The sugar industry was extremely worried about Yudkin’s growing influence and decided to embark on a major program to take the focus off sugar and direct it toward fats. Stare’s defence of sugar as a quick energy food that should be put in coffee or tea several times a day and calling Coca Cola a healthy between meals snack was welcomed by the industry.

As we have now learned from historical documents brought to light in a paper in the Journal of the American Medical Association, the SRF paid members of Stare’s department to carry out a literature review, overseen by Stare, designed to point a finger at fats while expressing skepticism about sugar’s supposed criminality. That review was published in the New England Journal of Medicine without any disclosure of sugar industry funding and successfully steered readers away from associating sugar with heart disease. While Stare, who died in 2002, was correct about many aspects of unfounded chemophobia, his reputation has now been tarnished by the undeclared payments received by his department from the sugar industry.

Sugar, as we now know, is not as innocent as Stare had claimed. But at least he never did suggest garlic in the rectum to cleanse toxins. As far as I know, neither has the Food Babe.

 

Dr. Joe Schwarcz  PhD

Critter Cuisine

entomophagyWe hear a lot about food these days. Whether it is about healthy choices, food security and feeding the planet, environmental impacts of food production or the science of GMO biotechnologies, hardly a day goes by without food appearing in our headlines.

Curiously, the most readily available source of low-fat animal protein found just about anywhere in the world (outside of Antarctica) is largely ignored by most food cultures. It might be time we start talking about eating insects, or entomophagy.

Putting our icky aversions aside for a moment, there are many good reasons to consider eating insects. Apart from their widespread availability in the wild, they can easily be raised indoors, with a fraction of the footprint (both in terms of land use and carbon emissions) of domestic livestock such as cattle or pork. Also, insect is a lean meat, with up to three times the protein content and with a fraction of the fat, with crickets compared to beef for example. Also, it is a versatile food, which can be eaten raw, cooked or processed, such as being dried and ground into a flour for baking.

Entomophagy is not new or strange to many people around the world, to be sure. One can easily find bulk crickets or woodworms in the markets of Singapore, or termites and grubs in the Ghanaian markets in Accra. Eating insects is also commonplace in cuisines from Brazil, Australia, Japan, China and more. So why is it that entomophagy still carries a taboo in Canadian/American cultures?

The answer may be partly psychological in nature, partly economic and the two are surprisingly linked. Clearly, our western culture carries with it a strongly ingrained entomophobia, or fear of insects, and we don’t tolerate them in our homes, on our lawns, in our crops or even in our thoughts. There is such a widespread phobia of creepy crawlies of any kind that billions of dollars are spent annually on the propaganda of their evil ways and on chemical pesticide solutions to their eradication from every corner of our lives.

This fanatical intolerance of insects was very deliberately fostered and nurtured by post-WWII chemical pesticide companies looking to promote the magical properties of their pesticides (like DDT) and bolstered by an imaginative TV and film media industry that created blockbuster entertainment about killer cockroaches, an attack of the giant ants or tales of mutant wasps that attack human brains via the ear canal. Ouch, scary stuff!

The net effect of this anti-insect campaign has been one in which most of us would rather squish a bug than pop it into our mouths. I am confident, however, that because this is a learned behaviour, it can be unlearned… or better yet, prevented in the first place by reaching out to children and teaching them about the joy and wonders of our critter cousins, before it is stamped out of them by society. Children are naturally curious about all aspects of nature and are particularly intrigued by bugs.

A few weeks ago, I was invited by the teachers at my 3-year old son’s Montessori school to give an insect-related show-and-tell. I managed to borrow several specimen of Stick Insects and Madagascar Cockroaches to bring in for the kids and I was thrilled to see the glee and eagerness from every child who wanted to touch and hold and play with these exotic insects. I kept thinking that the response would have been very different from an adult audience. What a shame it is that this joy of nature is bred out of us as a whole eventually.

Around 15 years ago, back when I was a keen Graduate student in an entomology lab at Laval University in Quebec City, I visited the Insectarium in Montreal for an insect-tasting event. In the foyer of the museum, a dozen chefs were set up behind linen-clothed tables and were preparing gastronomic cuisine of one kind or another, all of which involved insect ingredients. I eagerly ate a multi-course meal consisting in part of ginger-glazed scorpions, garlic-fried crickets, beetle flour cookies and angel-food cake garnished with zesty ants.

At some point during my entomological smorgasbord I noticed that I was being observed by a cautious and curious 8-year old boy, who seemed to take delight in the sight of a grown-up (sort-of) hungrily gobbling down some fried crickets, when I offered him a little taste. The boy reached out his hand to try one when he was noticed by his mother, who was standing just a few feet away.

In the blink of an eye, the poor boy was yanked by the arm, with a shriek from his mother, so brusquely that you could almost hear the socket pop! I mistakenly thought that they were here for an insect-tasting event…. apparently not.

Unfortunately, the boy was so traumatized by his mother’s reaction that it is most likely that his interest in insects was cut short on that very day, one in which a trip to the insectarium could have otherwise promoted a long-term fascination. Too often, our developed entomophobia is inherited directly from our parents, passed down from generation to generation.

We’ve got a long way to go as a society before we are collectively comfortable with all that insects may have to offer us in our lives and maybe even more to consider eating them as regular food.

So whether our conversation about food is related to the challenges of feeding 8 billion+ humans with a smaller ecological footprint or simply to explore the diversity of foodstuffs from the almost 1 million species of insects that exist, we need to start by shifting the flavour of the conversation first, from entomophobia to entomophagy.

Obviously, if we are to have any kind of positive conversation about bugs at all, we need to start with the children and to build pro-actively towards a society that can work with insects and not just against them. Maybe there would be a place for a new “Dickie Dee”-style street vending delivery cart for insect foods…. I can see it now: “Doc Brown’s Bugs ‘n Bites” will be the next food craze coming to a neighbourhood near you. Listen for the chimes as they come around the corner, playing something by The Beatles, of course.

Dr. Adam Oliver Brown

Here is a link to my Facebook page, where you can see some pics and videos of the insect visit with the school children: https://www.facebook.com/DrAdamOliverBrown/

A Holistic Nutritional Rockstar’s Rocky Science

margarineSometimes you can evaluate a person’s scientific acumen by a single comment they utter. This is the case with Catherine Sugrue who labels herself a “holistic nutritionist rockstar.” Of course suspicion about her knowledge is immediately raised when we learn that it was gained at the “Institute of Holistic Nutrition,” which isn’t exactly Harvard. But the giveaway of the rockstar’s untrustworthiness is her reiteration of the absurd statement that “margarine is about one molecule away from plastic.” This isn’t about coming to the rescue of margarine. I don’t like it and I don’t eat it. I much prefer butter. But I am piqued by the shoddy pseudo scientific exhortations of self-proclaimed experts. In this case I’m further annoyed that this particular pseudoexpert was interviewed for an article about fats that appeared not in the National Enquirer, but in the National Post. When there are Canadians like Yoni Freedhoff, Chris Labos and Tim Caulfield who actually are experts when it comes to nutritional issues and would never confuse the public with ludicrous analogies between margarine and plastic.

Margarine being “one molecule away from plastic” is just plain nonsense. Plastics are composed polymers while margarine is a blend of fats and water. There is no chemical similarity between the two. In any case, being “one molecule away” is a totally meaningless expression. Substances are made of molecules, which in turn are composed of atoms joined together is a specific pattern. I suppose one might say that hydrogen peroxide, H2O2, is one atom away from water, H2O, but even this is meaningless. That extra oxygen atom changes the properties of the substance dramatically. Sticking a finger into a bottle of pure hydrogen peroxide quickly reveals the effect of that extra oxygen.

So, even if margarine had some chemical similarity to plastic, which it does not, its properties could still be dramatically different. Slight alterations in molecular structure can account for very significant changes in properties.

It is true that saturated fats have been vilified beyond the scientific evidence but the pendulum is swinging too far in the other direction. Kourtney Kardashian attributing her 5 pound weight loss to drinking clarified butter every morning is without scientific merit. Catherine Sugrue correctly warns that “getting your nutritional advice from celebrities is a dangerous game.” But so is getting it from a self-proclaimed “holistic nutritional rockstar” who is a graduate of an institution where you can take continuing education courses in “energy medicine,” “clinical detoxification,” and “applied iridology.”

Joe Schwarcz PhD

Chemistry Lesson for The Food Babe…and everyone else #24

vani hariSince the late 1940s, so-called “subtherapeutic” doses of antibiotics have been routinely added to animal feed to prevent disease and to increase feed efficiency.  Exactly why animals put on weight more readily when exposed to small doses of antibiotics isn’t clear, but it may have to do with reducing the competition for nutrients by cutting down on the natural bacterial population in the animals’ gut.  Some studies also suggest that antibiotic use thins the intestinal wall and increases nutrient absorption.  What has become clear, however, is that such subtherapeutic use of antibiotics leads to the flourishing of antibiotic resistant bacteria in animals and that such bacteria can infect humans.  Chickens, for example, will begin to excrete antibiotic-resistant E. coli in their feces just 36 hours after being given tetracycline-laced feed.  Within a short time these bacteria also show up in the feces of farmers.  And a truly frightening prospect is that bacteria can pass genes between each other, including the ones that make them resistant to antibiotics.  This means that bacteria that have never been exposed to an antibiotic can acquire resistance just by encountering resistant ones.  Then consider that animals shed bacteria in their feces and that manure is used as fertilizer, and fertilizer gets into ground water, and it quickly becomes evident how the bacterial resistance problem can mushroom.

Thorough cooking of course kills bacteria, but the widespread incidence of food poisoning demonstrates that poor food handling and undercooking is common.  True, most people who come down with bacterial food poisoning just experience some unpleasant cramps and diarrhea and recover without the need for antibiotic treatment.  In this case resistance is not an issue.  But there are numerous cases of children, the elderly, or people whose immune system is compromised, who need antibiotic treatment for food poisoning.  And now if the bacteria are resistant to antibiotics, these patients can face a dire situation.  Take for example the case of an unfortunate Danish woman who died in 1998 after eating Salmonella-infected pork.  She failed to respond to ciprofloxacin (Cipro), the usual antibiotic of choice, because of bacterial resistance.  In a piece of elegant research, Danish scientists succeeded in genetically matching the Salmonella-resistant strain to a specific pig farm.  Surprisingly, these pigs had not been treated with ciprofloxacin, but the pigs on neighbouring farms had been, and the resistant bacteria had moved between farms!

In North America antibiotics known as quinolones have been used since 1995 to treat infections in poultry.  While this was great for the chickens’ health, it turned out not to be so good for humans.  The most common cause of bacterial gastroenteritis in people is Campylobacter jejuni, and poultry is often responsible.  If an antibiotic is needed, ciprofloxacin is the usual choice.  But since the introduction of quinolones to farm animals, Campylobacter strains resistant to the drug have emerged.  The Food and Drug Administration in the U.S. has recognized this as such a serious problem that it has made Baytril, a quinolone, the first veterinary drug to be banned because of the emergence of resistant bacteria.  While this is the first action of its kind in North America , Europeans have been phasing out antibiotics in animal feed since the 1980s.  Sweden banned the use of antibiotics as growth promoters in 1986 and Swedish farmers responded by improving hygiene on farms and by altering feed composition.  They showed that meat can be produced for the consumer at virtually the same cost as with antibiotics.  And without a cost to consumers’ health!  The European Union has followed suit and on January 1, 2006 banned the use of antibiotics as growth promoters in animal feed. That actually hasn’t resulted in a huge reduction in antibiotic use. While the prophylactic use has decreased, there has been an increase in the therapeutic use of antibiotics in animals because there has been an increase in illness that apparently was being prevented by antibiotics added to feed.

Antibiotics are wonderful drugs and we must do all we can to protect their efficacy.  While certain uses of antibiotics to treat sick animals are justified, as one scientist who studies antibiotic resistance opined, “Cipro is an essential antibiotic, and we cannot allow its effectiveness to be compromised by squandering it on poultry.”

Joe Schwarcz PhD

Chemistry Lesson for The Food Babe…and everyone else #20

vani hariOrganic farmers are allowed to use a number of pesticides as long as they come from a natural source. Pyrethrum, an extract of chrysanthemum flowers, has long been used to control insects. The Environmental Protection Agency in the U.S. classifies it as a likely human carcinogen. There you go then, a “carcinogen” used on organic produce! Does it matter? Of course not. Just because huge doses of a chemical, be it natural or synthetic, cause cancer in test animals, does not mean that trace amounts in humans do the same. Furthermore, pyrethrum biodegrades quickly and residues are trivial. But that is the case for most modern synthetic pesticides as well! And how about rotenone? This compound was discovered in the 1800s in the extracts of the root of the derris plant. Primitive tribes had learned that the ground root spread over water would paralyze fish which then floated to the surface. Rotenone is highly toxic to humans and causes Parkinson’s disease in rats. It has been used by organic farmers to control aphids, thrips, and other insects on fruit although it is being phased out. Residues probably pose little risk to humans, but synthetic pesticides with the same sort of toxicological profile have been vilified.

Organic farmers are also free to spray their crops with spores of the Bacillus thuringiensis (Bt) bacterium which release an insecticidal protein. Yet, organic agriculture opposes the use of crops that are genetically modified to produce the same protein. Isn’t it curious that exposing the crop to the whole genome of the bacterium is perceived to be safe, whereas the production of one specific protein is looked at warily? The truth is that the protein is innocuous to humans, whether it comes from spores sprayed on an organic crop or from genetically modified crops. True, organic produce will have lower levels of pesticide residues but the significance of this is highly debatable.

A far bigger concern than pesticide residues is bacterial contamination, especially by potentially lethal E. coli 0157:H7.  The source is manure used as a fertilizer. Composted manure reduces the risk, but anytime manure is used, as of course is common for organic produce, there is concern. That’s why produce should be thoroughly washed, whether conventional or organic. Insect damage to crops not protected by pesticides often leads to an invasion by fungi. Some fungi, like fusarium, produce compounds which are highly toxic. Two varieties of organic corn meal once had to be withdrawn in Britain because of unacceptable levels of fumonisin, a natural toxin.

Are organic foods more nutritious? Maybe, marginally. When they are not protected by pesticides, crops produce their own chemical weapons. Some of these, various flavonoids, are antioxidants which may contribute to human health. Organic pears and peaches are richer in these compounds and organic tomatoes have more vitamin C and lycopene. But again, this has little practical relevance. When subjects consumed organic tomato puree every day for three weeks, their plasma levels of lycopene and vitamin C were no different from that seen in subjects consuming conventional puree. In any case, we simply are not going to feed 7 billion people organically.

Joe Schwarcz

Love it or Hate it

cilantroWhen it comes to food, everyone has likes and dislikes. Chocolate generally gets favourable comments, spinach less so. But no flavour seems to elicit the degree of polarizing comments as that of cilantro. There are websites and Facebook groups dedicated to demonizing cilantro, likening its aroma to soap or curiously, to dead bugs.

The seeds of the cilantro plant are known as coriander and are even mentioned in the book of Exodus. Archeologists found some in King Tutankhamen’s tomb, perhaps placed there with hopes of adding some spice to the afterlife. The ancient Chinese believed there would be no need to worry about the afterlife if you consumed cilantro because the herb conferred immortality. Hippocrates used it as medicine and even today some people ascribe health benefits to the herb based on its content of antioxidants, anti-bacterial compounds and minerals. These, though, are not unique to cilantro, all plants contain varying quantities of these substances.

Another supposed benefit is cilantro’s ability to chelate heavy metals. The term “chelate” comes from the Greek meaning “claw” and refers to compounds that have the ability to remove harmful metal ions from solution by gripping them like a claw. Some bloggers even push cilantro as an ingredient in a “detox” salad, claiming it rids the body of heavy metals. As usual, there is a kernel of truth to the claim, but that kernel is inflated with nonsense until it pops.

A few studies have shown that cilantro leaves can produce a chelating effect in water spiked with heavy metals and that cilantro can reduce absorption of lead when food tainted with it is fed to mice. But these effects are light years from a salad with cilantro accomplishing any sort of heavy metal “detoxing” in people. Such a claim would require a demonstration of there being a heavy metal problem in the first place and its reduction with cilantro. A PubMed search for “cilantro detox” yields zero entries. Similarly, there is no basis to some food faddists’ claim that “cilantro can reduce water weight, is a cancer fighter and can improve memory with its brain protecting vitamins and minerals.”

While the scientific literature provides no evidence for health benefits, it does provide clues when it comes to cilantro’s polarizing flavour. What we refer to as flavour is the sensation triggered when molecules in food encounter receptors on our taste buds and in our nasal passage. Indeed, scent is an integral part of the sensation as evidenced by cilantro haters not being bothered if they consume the herb while holding their nose.

Some forty compounds have been isolated from cilantro including a number in the aldehyde family that are mainly responsible for the aroma and taste. The composition of the seeds is somewhat different, having linalool, also found in lavender and cannabis, as a major component. It has a pleasant floral scent accounting for its use in cleaning agents, detergents and shampoos. When inhaled it can reduce stress. At least in lab rats. Rats that inhaled linalool saw a reduction in the elevated levels of white blood cells induced by stress.

It is the aldehydes in cilantro that cause some people to liken the scent to soaps and lotions because these compounds are indeed found in those products. But why only some people? One theory is that the cilantrophobes are “supertasters” and can taste compounds that others can’t. Supertasters do exist, but they react to very specific bitter compounds such as propylthiouracil, while most people taste nothing. However, there are no such compounds in cilantro and “supertasters” are no more likely to be cilantro haters than anyone else.

It seems, though, that people ho abhor cilantro may have some sort of genetic connection, if we go by an interesting study carried out by Dr. Charles Wysocki of the Monell Chemical Senses Center in Philadelphia. Taking advantage of the annual twins festival in Twinsburg, Ohio, Wysocki had identical and fraternal twins rate the scent of chopped cilantro. There were definitely lovers and haters, with identical twins almost always agreeing with their sibling, which was not the case for fraternal twins. Experiments at Monell have also separated the components of cilantro using gas chromatography and showed that while everyone can smell the “soapy” aldehydes, cilantro haters cannot smell the compounds that make the herb so attractive to its fans.

Interestingly, there is also an ethnocultural connection. A study at the University of Toronto surveyed 1639 young adults and had them rate their preference for cilantro on a 9 point scale. East Asians were the most likely to dislike cilantro with roughly 21% expressing their distaste. Caucasians were not far behind at 17%. Only 14% of those of African descent disliked the taste, followed by South Asians at 7%, Hispanics at 4% and Middle Eastern subjects at 3%. These stats roughly parallel the use of cilantro in the cuisine of these areas suggesting that there is a connection between liking cilantro and frequency of exposure.

While cilantro’s enemies would rather stick rusty needles into their eyeballs than eat the fresh herb, they normally don’t object to cilantro in cooked foods such as pesto. That’s because the herb’s flavor changes as the volatile aldehydes escape into the air when it is crushed, cooked or pureed. Cilantro fans of course crave fresh cilantro and when cooking add the herb at the end stage. As for me, I’m with Julia Child on this one. Back in 2002 she told Larry King in an interview that if she found cilantro in a dish she was served she would pick it out and throw it on the floor. I recognize, though, that there are people who would jump to catch it before it hit the ground because they just love the smell and taste of this herb that has pleased some and irritated others since biblical times.

Joe Schwarcz PhD

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