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There are no fish genes in tomatoes

tomatoesDuring a public lecture on genetic modification I described an experiment that involved enriching soybeans with the amino acid methionine. Soybeans are widely used to raise animals but are low in this essential amino acid often necessitating the use of methionine supplements. Brazil nuts produce a protein that is particularly rich in methionine so the idea was to isolate and clone the gene that codes for the production of the methionine-rich protein and insert it into the genome of the soybean.

This raised an obvious concern. Although the modified soybeans were to be used mostly for poultry, the possibility that they could somehow end up in human food had to be considered. What if a person allergic to Brazil nuts happened to consume these soybeans, possibly triggering a life threatening reaction? Testing of blood drawn from people allergic to Brazil nuts revealed that the antibodies they had produced in response to ingesting Brazil nut proteins also latched on to proteins in the engineered soybeans, indicating the potential for an allergic reaction. As a result the research was abandoned and the modified soybeans were never produced.

The first comment after my talk picked up on the allergen issue. “If genetically modified foods were properly labeled, I could still eat tomatoes,” was the angry remark. I was puzzled by this, but the gentleman went on to clarify. “I have a fish allergy,” he said, “and I have no way of knowing which tomatoes have been modified with fish genes, so I just don’t eat any tomato products.” He need not have worried. There are no fish genes in tomatoes, and if there were, the tomatoes would have to be so labeled according to existing regulations. What we have here is fear generated by misinformation.

The Arctic flounder lives happily in the ice cold waters of the Arctic Ocean, its blood prevented from freezing by an “antifreeze protein.” Since tomato growers live under the threat of a sudden freeze destroying their crop, researchers wondered about the possibility of inserting the flounder gene that codes for the antifreeze protein into the genome of the tomato. Preliminary experiments showed that in plants this protein was not effective in preventing ice crystal formation and the project was dropped. But on the Internet, no story ever dies. The “fish genes in tomatoes” myth lives on, often illustrated with syringes plunged into tomatoes, or drawings of tomatoes shaped like fish. Had the technology proved promising, it would have required extensive testing of the specific fish protein used to determine if it was involved in producing an allergic reaction.

Such testing is not required when novel conventionally produced foods are introduced into the market place. Kiwis are an interesting example. Allergy to the fruit did not exist in North America until some thirty years ago for the simple reason that kiwis were not eaten. With the expansion of global marketing kiwis are now found in every supermarket and correspondingly, allergies have increased. Introducing a novel fruit, like the kiwi, introduces hundreds of novel proteins, many with allergenic potential. On the other hand, genetic modification commonly introduces only one specific protein, meaning a reduced chance of an allergic reaction. This suggests that as far as allergies go, it is more important to focus on new foods, not on genetically modified ones. As people eat a wider variety of foods they will develop a wider variety of allergies, but this problem doesn’t get nearly as much attention as the potential reaction to a single protein in genetically modified food.

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Does Hydroquinone Have a Dark Side?

hydroquinoneThey were once mistakenly thought to be caused by a disease of the liver, so they are called “liver spots.” Actually these skin blemishes are caused by a buildup of the skin pigment melanin and are associated with aging and long-term exposure to ultraviolet light. Technically referred to as “Lentigo senilis,” these hyperpigmented spots usually just present a cosmetic problem unless they develop irregular borders and undergo a colour change, in which case they need to be evaluated by a physician. People bothered by such “senile freckles” can look to hydroquinone for help.

When applied as an ingredient in a skin cream, this chemical inhibits the activity of tyrosinase, an enzyme that is necessary for the formation of melanin. This brings up three questions. How well does hydroquinone work, what concentration is needed, and what risks, if any, does its use present? Hydroquinone does work, and its efficacy, as is to be expected, is dose related. Need a minimum of 1% in a cream to see any result, and really significant effects kick in at 4%. In the U.S., hydroquinone is available in over the counter products at concentrations up to 2%, anything more than that requires a prescription. In Europe and in Canada all hydroquinone products require a prescription. Why the difference?

Different regulatory agencies arrive at decisions in different ways. In this case, Europe and Canada look at worst case scenarios while the U.S. evaluates hydroquinone based on its actual use in cosmetics. Rat feeding studies have suggested that hydroquinone may be carcinogenic, although this is contentious. In humans, in rare cases, accidental ingestion of photographic developer fluid containing hydroquinone has resulted in toxic reactions, but in a controlled trial with human volunteers, ingestion of 300-500 mgs daily for months produced no observable effects. As far as topical application goes, no systemic reaction has ever been noted, and no link to skin cancer has ever been found. But there is a chance of skin irritation, especially if sun protection is not used after application, as well as a rarely seen blue discoloration known as “ochronosis.” With higher concentrations there is the possibility of losing too much pigment resulting in white spots. It is mainly for the latter reasons, and some concern that hydroquinone has not been studied with enough rigour, that Canada and Europe are concerned about over-the-counter availability.

But aside from hydroquinone products that have been adulterated with mercury compounds, which has happened in Africa, no significant problems with 2% solutions have cropped up. Hydroquinone also occurs in nature, found in the bearberry, madder and mulberry plants, extracts of which are touted as “natural skin lightening agents.” These do work, but whatever issues arise with hydroquinone apply to these preparations as well. The fact that the hydroquinone comes from a natural source is irrelevant. Basically, 2% hydroquinone preparations, no matter what the source, can reduce age spots effectively and the alarm sounded by some activist organizations about such products is not backed up by evidence.

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VegeGreens products’ unfounded claims hide behind great marketing

vegegreensI opened the door to pick up my morning Gazette and found a package with an anonymous note. “Can you please discuss in a column whether this is good to take?” Inside was a bottle of “VegeGreens.” Although I had not previously encountered this specific product, I have looked into other such concentrated powders that claim to deliver the nutritional benefits of fruits, vegetables and grains, eliminating the need to track the recommended daily servings of these foods.

VegeGreens contains components from just about every vegetable, fruit, grain, oil and herb for which health claims have been made in the pages of health food magazines or on various websites. Consider, for example, oat bran powder. There actually is some evidence that beta-glucan found in oat bran can reduce cholesterol, but you need about 3000 mg a day. How much does a serving of VegeGreens contain? Thirty mgs! An inconsequential amount. The label on the bottle features a banner “blueberry medley,” an obvious attempt to capitalize on research showing the benefits of blueberry consumption. How many blueberries have made it into this wondrous powder? Not even one! The total amount of blueberry concentrate is 50 mg. How about resveratrol, the supposed healthy ingredient in red wine? That’s in here as well, to the extent of 2.5 mg. Any potential benefit requires hundreds of milligrams. And so it goes. The amount of green tea extract is not even equivalent to one sip of tea, and the amount of ginkgo biloba is 20 mgs, which is less than one tenth of the dose used in studies that have claimed to improve memory.

While each component of VegeGreens is present in doses that are much smaller than those used in studies, most of which are less than compelling in any case, there is still the possibility that this curious blend of some sixty ingredients provides a benefit. Is there any evidence provided? All we are told is that the company “takes the holistic approach of selecting and testing every ingredient to ensure they are in balance with each other and with your body.” Really? Where are the studies to show such balance, whatever that means?

We are also comforted with the info that this supplement is professionally formulated and “energetically tested.” The professional involved seems to be a naturopath whose claim to fame is that he is a recognized authority in the field of “auriculotherapy” and “therapeutic drainage.” Auriculotherapy is based on the idea that the ear is a microsystem of the entire body and that stimulation of certain points on its outer portion can treat disease. Needless to say, there is absolutely no scientific evidence for this. Therapeutic drainage “is the process of detoxifying the body by opening the elimination channels in the excretory organs and releasing toxic accumulations.” This is achieved by administering homeopathic remedies, which by definition are so dilute as to essentially contain nothing. So much for the “professional design.” How about energetically tested? Perhaps that refers to the energy that has gone into marketing.

Now, for some of the direct claims made on behalf of VegeGreens. “Restores a healthy pH.” Our blood is a buffer system that automatically controls pH. “Detoxifies the body.” Really? What toxins are removed and how were these identified? “Renews mental clarity.” Studies please! “Promotes clear, healthy skin.” How about some before and after pictures? “Balances blood sugar.” Blood sugar is easy to measure. Where is the data to show that this product balances it? “Strengthens the immune system.” What does that mean? The immune system is very complex and involves organs, white blood cells, antibodies, enzymes, complement proteins, interferon and lymphokines. Which of these has been shown to be affected by VegeGreens? If any such studies exist, they are certainly not referenced. Instead we get the usual anecdotal accounts. “VegeGreens are amazing! I feel so energized and clear-headed when taking it,” one satisfied customer opines. And a sports trainer chimes in with “trust me, I have tried every vitamin company out there and this one makes the purest and most researched supplements available.” Not exactly the scientific method, is it?

I don’t think there is any harm in VegeGreens or any of the numerous similar products out there. They may even provide some benefits for people who have a low fruit and vegetable intake. But we don’t know because there are no studies. There are just unsubstantiated claims made by promoters who have a homeopathic knowledge of nutrition. I would have been happier to find a basket of fruits and vegetables on my doorstep.

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But it’s natural…

jimsonweedThe first British settlement in North America was established in 1607 and was named Jamestown, after King James I.  It was a little tobacco growing colony located on the east coast, in the region which was eventually to become the state of Virginia.  One of the constant debates among the settlers was whether or not to expand the colony.  There was great profit to be had in tobacco growing, especially since labor was cheap; the settlers of Jamestown had brought the first African slaves to North America.  On the other hand, the settlement was surrounded by unfriendly natives who, of course, opposed expansion.

Nathaniel Bacon, a member of the Governor’s Council, was one of the greatest advocates of expansion.  In 1676 he took the law into his own hands and organized an expedition against the Indians.  Governor William Berkley, fearing a large scale war, denounced these activities and sent his soldiers to quell what history has recorded as the “Bacon Rebellion.”  The soldiers began to mobilize for the expected battle which never took place.

Camped out in a field, the soldiers cooked up a stew which they flavored with what they thought was an edible plant.  A most remarkable picture began to unfold minutes after they had downed the food.  All thoughts of battle disappeared as soldiers began to run around laughing, giggling, yelling at each other with slurred speech.  The delirium continued for eleven days.  The Governor’s army had been defeated not by Bacon’s men, but by atropine,a naturally occurring chemical  found in a lowly weed, known to this day as Jamestown weed, or in a corrupted form, jimsonweed.

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You Asked: Can the much advertised Lipozene lead to weight loss?

lipozeneThe “active” ingredient in Lipozene is glucomannan, a form of dietary fiber that is extracted from the root of the konjac plant. Fiber, by definition, is any type of food component that cannot be digested and consequently makes its way to the large intestine or colon, where bacteria may break it down into smaller compounds. Most of these, along with intact fiber, are excreted. Glucomannan is made of glucose and mannose molecules joined together in long chains, but unlike digestible carbohydrates like starch, it is resistant to breakdown by our salivary or pancreatic enzymes.

As the indigestible glucomannan sits in the stomach or small bowel before passing on to the colon, it absorbs a great deal of water. This bulky mélange of water and fiber makes for a feeling of fullness and curbs the appetite. There have actually been a few short term studies indicating more efficient weight loss on a low calorie diet when it was combined with about 4 grams of glucomannan per day.
Marketers take such studies and inflate them with hype about easy weight loss. They promise weight loss without the need to diet or exercise. Of course this is a promise that cannot be fulfilled, which is the reason that an American company called Obesity Research Institute was taken to task by the Federal Trade Commission and was made to return 1.5 million dollars to customers who had been victimized by unsubstantiated claims. Two physicians who appeared as “expert endorsers” on infomercials produced by the company were also reprimanded. Seems that money can blur scientific vision.

This is not to say that glucomannan in combination with a low calorie diet and exercise cannot aid in weight loss. It can. But it is not a long term answer to the problem of weight control. This fiber does, however, provide some other possible benefits. It slows the absorption of other carbohydrates into the bloodstream and provides better control of blood glucose. Glucomannan also interferes with cholesterol uptake, so it can lead to lower blood cholesterol. For those in need, it can also be an effective laxative. And if you pop a couple of glucomannan pills before grocery shopping you will feel more full and buy less!

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You Asked: Is it true that some baloney is made with ground-up earthworms?

baloneyAbsolutely not. But here is the question I got: “A friend told me that that ground up earthworms are being used as fillers in many meat products like wieners and bologna. The name on the package is sodium erythorbate. I’ve checked packages at stores here and have found only one brand without this ingredient. My little boy loves hot dogs and I hate to think how many I’ve fed him over the past several years with earthworms in them.”

Hard to know how such silly stories arise. Maybe it is the similar sounds of “erythorbate” and “earthworm bait.” Sodium erythorbate is just a form of Vitamin C and is used as a preservative. It also prevents the formation of potentially carcinogenic nitrosamines is meats processed with nitrite.

Erythorbate is a perfectly safe substance and has absolutely nothing to do with earthworms. It makes a lot more sense to minimize hot dog and baloney consumption because of their high fat and salt content than because they contain sodium erythorbate. There is more baloney in the sodium erythorbate story than there is sodium erythorbate in the baloney.

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Leave the donkey milk to donkeys

cleopatraCleopatra supposedly took a daily bath in milk supplied by a herd of some 700 lactating donkeys. How she hit upon this idea isn’t known, but the legendary beauty may have been familiar Hippocrates’ recommendation that donkey milk was an effective treatment for fever, liver problems, joint pain and poisoning. If it was good for the inside, maybe it was good for the outside as well! Since donkeys don’t produce much milk, lots of lactating females are needed to fill a bathtub.

Should you contemplate following in Cleopatra’s footsteps and plunking yourself in a leisurely bath of donkey milk, you would need the riches of an Egyptian queen. Donkey milk goes for about forty dollars a liter! And you’ll have to travel quite a distance to find it. Specialty shops in Cyprus sell it for its supposed health benefits with scant evidence.
A researcher at the Cyprus University of Technology did follow people who drank donkey milk for months and found they reported improvement with asthma, coughs, eczema and psoriasis. Not exactly a clinical trial, but interesting, given that of any mammal, donkey milk is the closest in composition to human milk which is known to help build an infant’s immune system. Like humans, and unlike cows, donkeys have only one stomach and don’t rely on as large a variety of bacteria to digest their food as do cows with their complex four-stomach fermentation process. Initial studies also point to more active anti-bacterial agents in donkey milk.

Such bits of anecdotal evidence often excite marketers who are on the lookout for a product that can be promoted as the newest miracle elixir. They got unexpected support from of all people, Pope Francis, who revealed that he was fed donkey milk as a baby. Still, donkey milk itself is not likely to take off due to its cost, but donkey milk products may get a boost. Cosmetics that contain the milk and soaps made from the fat in the milk are available. And they have their fans with people claiming that beard itchiness and eczema on hands clear up with the use of donkey milk soap.

While taking baths in donkey milk is far-fetched, in Australia, “bath milk” can be purchased, usually in health food stores. It is actually raw cow’s milk and isn’t really intended to be used for bathing. Rather this seems to be an attempt to get around the ban of selling unpasteurized milk. Raw milk enthusiasts claim that pasteurization destroys nutrients in milk, leads to lactose intolerance, allergic reactions and destruction of beneficial bacteria. They furnish anecdotes about raw milk miraculously clearing up asthma, eczema and tooth decay. Interestingly enough, a study that followed almost a thousand infants in Europe found a roughly 30% reduced incidence of colds, respiratory tract and ear infections associated with drinking raw milk. The researchers conclude that “if the health hazards of raw milk could be overcome, the public health impact of minimally processed but pathogen-free milk might be enormous, given the high prevalence of respiratory infections in the first year of life.” That “but,” though is a big one. Milk needs to be heated to 72 degrees C for 15 seconds to destroy pathogens such as Salmonella, Listeria, and E. coli O157:H7.

A tragic case highlighting the importance of pasteurization occurred in Australia last year with five children falling ill and one dying after drinking raw milk that had been sold as “bath milk.” Such products are sold there in containers similar to regular milk and are often placed near regular milk in stores. Even though, as required by law, the label states that the milk is not for human consumption, it is clear that people who buy bath milk are not using it to fill their bathtubs. To remedy the situation, Australia has now passed a law stipulating that “bath milk” must either be pasteurized or be treated with a bittering agent that makes it unsuitable for drinking.

The law is predictably opposed by raw milk advocates who say that “you are allowed to smoke cigarettes and eat junk foods but you are not allowed to drink raw milk.” They say there should be a freedom of choice. Canada offers no such freedom, all sales of raw milk are banned. In the U.S., milk sales are under state jurisdiction and some, like California, allow retail sales. Supposedly raw milk there comes from farms where farmers somehow assure their animals do not produce contaminated milk. Presumably they would also be allowed to sell unpasteurized donkey milk. And in California there would probably be a market.

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The Death of Smallpox

smallpoxEdward Jenner, an English country doctor is usually credited with introducing the idea of vaccination because of his landmark publication in 1798 in which he described inoculating 23 people with pus from smallpox postules. Normally they would have been expected to come down with the disease. But none did!  Why? Because Jenner had previously exposed them to a disease that was well-known among milkmaids, known as cowpox. Somehow this exposure conferred immunity to the far more serious smallpox.

Actually, Jenner did not come up with the idea of vaccination. That honor should really go to some unidentified Turkish whiz in the 16th century. But if we must connect a name with the discovery, how about Lady Mary Wortley Montagu, the wife of Britain’s ambassador to Turkey in the 16th century. It was the gentle lady’s habit to put on disguises and roam the streets of Constantinople. During one of these incognito capers she came upon an old woman who had a reputation for protecting children against smallpox. Her technique must have seemed absurd. She would scratch a vein in a child’s arm and introduce some liquid from a smallpox postule. The story that Lady Montagu heard was that these children might get mildly ill, but never got smallpox!

This apparently bizarre approach did seem to make sense. It was well known at the time that someone who survived smallpox, would never get the disease again. So why not give the disease to the young and healthy who had the best chance of recovery? Lady Montagu, upon her return to England, suggested that the practice of inoculating children in this fashion should be introduced but was roundly condemned for proposing such a preposterous idea. How dare anyone suggest that the youth of the nation should be purposely made ill? The Church also put in its two bits. God’s laws must not be interfered with! Seemingly only a layman, Robert Sutton, showed any real vision, perhaps prompted by the chance to cash in on the discovery. He opened a vaccination center in Essex and inoculated more than 17,000 people with smallpox extract only five of whom died.

In 1774, farmer Benjamin Jesty followed in Sutton’s footsteps. He had noted that milkmaids sometimes came down with a disease that resulted in postules on their body. These looked to him to be very similar to smallpox postules, and using a darning needle, he inoculated his wife and two sons with pus he had withdrawn from a victim. Then sometime later, he exposed them to smallpox and found they were unaffected. Edward Jenner heard about this story and it sparked his interest because he himself had been inoculated with smallpox when he was a boy. Now, for the next twenty years Jenner observed milkmaids who had come down with cowpox and found that they never contracted smallpox. So finally in 1776 he inoculated eight year old James Phipps with cowpox and then exposed him to smallpox. The boy did not get the disease. This prompted further trials and resulted in the publication of Jenner’s paper in 1798. By 1801 about 100,000 people in Britain had been vaccinated.  Jenner was knighted and got a prize of ten thousand pounds. The term vaccination?  Of course it comes from the Latin word for cow!  Now you know why.

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