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Seedy business in grape seed extracts

grapesA modest amount of red wine reduces the risk of heart disease, possibly because of the polyphenols it contains. Grape seed extract contains the same polyphenols as found in wine and has therefore been widely marketed as a dietary supplement with claims of having a beneficial effect on the human cardiovascular system. The problem here, though, is that the studies that have explored the effects of grape seed extract on human subjects have shown either none or minimal benefits. One study showed a slight increase in the resting diameter of the brachial artery in the arm, a finding of unknown clinical significance.

A meta analysis of nine randomized controlled trials concluded that grape seed extract had no effect on blood cholesterol, inflammation as determined by C-reactive protein levels, or triglycerides. There was a slight decrease of 1.5 mm Hg in systolic blood pressure, which is minimal when compared with what can be achieved with medication.

Overall there does not seem to be much evidence for taking grape seed extract supplements, although given that there is a great variety in supplement composition, it is possible that some specific supplements may be more effective than others. Unfortunately there are no quality control standards, as is clearly demonstrated by a recent analysis of 21 extracts purchased from a variety of outlets. Compared with authentic grape seed extract, there was great variability in chemical composition of the commercial extracts, but on average they all contained significantly less polyphenols than the authentic samples.

That, though, was not the only problem. Six of the samples contained no detectable quantities of grape seed extract, but were instead composed of peanut skin extract. Peanut skin does contain a variety of polyphenols similar to that found in grape seeds but the presence of peanut extract raises the issue of allergenicity. It is certainly possible that people with a peanut allergy may react to the adulterated extract. The motivation for such adulteration is financial, since peanut skin extract is much cheaper than authentic grape seed extract. Adulteration and lack of reliable data about composition is not the only problem. Let’s remember that even with authentic grape seed extract there is no compelling evidence of health benefits. And what about that glass of red wine with dinner? Drink it because you like it, not because of the polyphenols it contains. And we won’t even mention that ethanol is a carcinogen.

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Strange Treatments

Today we have a pretty good grasp of what causes illness. We know about infections, carcinogens, pollution, genetics, anatomical abnormalities and the consequences of a poor diet. We also have effective pharmaceutical and surgical treatments, albeit not always as effective as we would like. But at least they are based upon science. But that has only been the case since we’ve had a good grasp on how the body functions, which is basically the last hundred or so years. Before that desperate people resorted to some pretty wacky treatments, at least wacky in retrospect. At the time I suppose they seemed rational. The ancient Greeks introduced the idea of “like cures like,” later adopted by homeopaths. A poisonous snake was unaffected by its own poison, so Greek physicians believed snakebite should be treated by applying the flesh of a snake, or a concoction made by boiling a snake, to the wound.

This same principle was used in the fourteenth century when Europe was struck by the Black Death. This plague which killed about a million and a half people in Britain alone was believed to be spread by bad smells. That of course was not the case. The plague is a bacterial infection that is spread by fleas which live on rodents such as rats. Rodents are more likely to inhabit filthy areas which smell so there may actually be an association between the plague and smells but the smell does not cause the disease. Nevertheless, the belief was that the disease was caused by deadly vapors, and in the spirit of like cures like, the foul vapors could be warded off by other evil smells. Some physicians even recommended keeping goats inside homes to produce a therapeutic stink. Even more bizarre was the suggestion of using human flatus which was supposed to be stored in a jar and inhaled when the plague struck. How people were supposed to make the collection isn’t clear.

The flatus treatment sounds just about as crazy as a doctor’s recommendation in 1728 for curing coughs with snail syrup. Take garden snails, early in the morning while the dew is upon them, he said, take off their shells; slit them; and with half a pound of sugar, put them in a bag and hang them in a cellar and the syrup will melt and drop through, ready to be swallowed when a cough appears. That recommendation is about as hard to swallow as the snail juice. Modern science hasn’t wiped out all outlandish therapies. In Hong Kong snake soup remains the remedy for a cold with venomous snakes like the king cobra being the most highly prized ingredient. Sometimes a living snake is skinned and the gall bladder removed to be used as a cure-all. The treatment does have a dangerous side effect. Escape of snakes from shops is a problem.

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You Asked: Blueberries and Milk

blueberries and milk“I put blueberries and milk on my cereal in the morning. Which one should I give up?” That was the question I received via email. A reference was included to a study about the antioxidant activity of blueberries being impaired when consumed with milk, as well as one about milk consumption being linked to greater risk of bone fractures and to earlier mortality. While both these studies appeared in the peer-reviewed literature and are interesting, their practical significance is questionable.
The milk study focused on people drinking more than three glasses of milk a day and could not rule out “reverse causation,” namely that some subjects were drinking more milk because they already had risk factors for osteoporosis. As far as earlier mortality goes, the authors suggest it may be linked to an inflammatory effect attributed the galactose, a breakdown product of lactose, the sugar found in milk. But this is pure conjecture. It is also possible that people who drink a lot of milk have a higher calorie intake or a lower vegetable intake, or exercise less, all of which can be confounding factors. Milk may not be as important a dietary component as Canada’s Food Guide suggests, but there is no need to avoid it. Moderation is the key.

Blueberries are widely perceived as “healthy” based upon their content of antioxidants. These naturally occurring substances are found in numerous fruits and vegetables and are thought to be responsible for the benefits attributed to a diet that contains lots of plant products. Laboratory investigation can determine the antioxidants present in food but to what extent they are absorbed into the bloodstream is a more difficult question. We don’t eat single food components, we eat food. Studies have shown, for example, that polyphenols, a family of antioxidants found in tea, are more poorly absorbed when milk is added to tea because proteins in milk bind to the polyphenols. The blueberry study aimed to investigate the fate of two particular antioxidants, namely caffeic and ferulic acid when consumed with or without milk. Eleven subjects, a very small number in terms of scientific studies, consumed 200 grams of blueberries either with 200 mL of whole milk or 200 mL of water. For two days prior, the subjects were asked to abstain from foods containing antioxidants including all fresh fruits and vegetables as well as tea, coffee, juices, wine and chocolate. This unrealistic eating pattern already adds confusion to the study.

In any case, analysis of the subjects’ plasma indicated a somewhat reduced antioxidant content when the blueberries were consumed with milk. This has little relevance to health. Blueberries are not commonly consumed with milk, except perhaps when they are eaten together with cereal. And there is no compelling evidence that the antioxidant content of plasma is a determinant of health. Furthermore, the plasma’s antioxidant potential is determined by the overall content of the diet and is not going to be affected to any significant extent by the handful of blueberries added to cereal whether consumed with or without milk.

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Let’s preserve rational thinking when it comes to preservatives

preservativesOpen a box of old crackers or potato chips and a smell emerges. It isn’t pleasant. The same goes for that bottle of oil that’s been sitting in the cupboard for months. It’s the smell of rancid fat. Technically speaking, the smell, which consists of numerous compounds, is the result of oxidation. Simply put, that means fats have reacted with oxygen in the air causing them to break down into smaller molecules. Not only are these malodorous, detectable at an unbelievably low concentration of 1.5 picograms per liter of oil, they can have nasty health consequences. It is not a good idea to eat foods in which the fat has gone rancid. Annoyingly, it is the healthier, polyunsaturated fats, that are more prone to rancidity. These fats have multiple double bonds in their molecular structure, a feature that enhances reaction with oxygen. Initially the fats are converted to hydroperoxides which are unstable and decompose to yield compounds like vinyl ketone, nonadienal and malondialdehyde. On top of having very low odour thresholds, some of these, malondialdehyde specifically, can cross-link proteins and DNA molecules and that is bad news. Such an affront to DNA can trigger cancer.

Knowledge of the mechanism of such oxidation reactions has led to the use of “antioxidants” that react with hydroproxides and prevent their breakdown. The most effective ones have the tongue twisting names of butylated hydroxytoluene (BHT) and butylated hydroxyl anisole (BHA) which are added to foods containing solid fats or oils such as shortenings, baked goods and cereals. These chemicals are not just randomly added, like all other food additives, their use is strictly regulated. Manufacturers can add BHA or BHT up to 0.02% of the weight of the fat in a food which is an amount determined by extensive studies on animals.

Of course if you give enough of any chemical to a test animal something will eventually happen. For example, BHA can cause carcinomas in the forestomach of rodents at a dose of 230 mg per kg per day. Internet bloggers can parlay that into scaring consumers who are unaware of the principles of toxicology and species differences. Humans do not have a forestomach and human exposures are actually less than 0.1 mg/kg/day. So while BHA can indeed be declared to be an animal carcinogen, this has no relevance to humans. On the contrary, studies have shown that at concentrations of 125 ppm which is close to food additive levels, both BHA and BHT have anticarcinogenic properties. Not only have there been no studies correlating these additives with human cancer, rates of stomach cancer have ben significantly decreasing possibly due to the use of preservatives.

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A Hot Potato

friesThe poor potato is being mashed by criticism.Too high a glycemic index, critics say, which means more sugar in the bloodstream for anyone concerned about diabetes. Forget about eating potatoes, say the proponents of low carb diets. French fries? Forget it. Loaded with fat. And supporters of California’s Proposition 65, which stipulates that any substance that has been linked to cancer must be clearly identified, clamor for potato chips to sport a label stating that they contain acrylamide, which is “known to the State of California to cause cancer.” Acrylamide forms when heat causes asparagine, an amino acid present in numerous foods, to react with starch. Potatoes have asparagine and starch, and when it comes to baking or frying, can indeed form acrylamide.

Technically this is a carcinogen because it can cause cancer in animals albeit only when they are treated with doses far greater than human exposure. No epidemiological studies have demonstrated that the traces of acrylamide to which we may be exposed in baked goods, coffee, cereals or potatoes play a role in human cancer. But California politicians argue that less exposure to a carcinogen is always better, and that people should know where such substances are found so they can take appropriate measures. This argument does not fly with most toxicologists who maintain that even with carcinogens there is a threshold effect below which there is no risk.

No matter whether the risk is real or not, reducing the possibility of acrylamide formation can be an effective marketing tool. So along comes the “Innate” potato, developed by the J.R. Simplot Company in the U.S. With its reduced asparagine content it will have less acrylamide when baked or fried. But there is an issue here that may not play so well in the marketplace. The new-fangled potato is a product of genetic engineering. The gene that codes for the production of asparagine, as well as one responsible for the browning of potatoes, has been silenced through a process known as “RNA interference.” This does involve the incorporation of novel genes into the Innate potato, but those genes come from other varieties of cultivated and wild potatoes. No genes from any other species are introduced.

Stll, there are critics who contend that RNA interference technology has not been studied well enough, and that asparagine may also play a role in defending the potato against disease causing organisms. And then there is the issue of implying that a “safer” potato has been engineered which can lead to less vigilance about eating fried potatoes. Realistically, the health concern about French fries is the amount of fat they harbour, not their acrylamide content. It is extremely unlikely that there is any health risk arising from consuming this genetically engineered potato, about as unlikely as there being any risk associated with the traces of acrylamide in foods we eat. Basically, though, this new potato is a solution to a problem that never existed.

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Seeds of Hope

seeds of hopeWhy would anyone oppose a technology that dramatically increases crop yields and protects farmers from excessive exposure to pesticides? Because of irrational fears about the technology involved, which is of course genetic modification. A battle is now brewing in India and Bangladesh over the planting of eggplant that has been genetically modified to resist attack by insects. Eggplant is a staple in many dishes in India and Bangladesh but unfortunately the plant is susceptible to attack by the fruit and shoot borer and farmers have to spray to prevent infestation on a regular basis.

Most farmers are poor and are not well trained in pesticide use and put themselves at risk. But a gene from the soil bacterium Bacillus thuringiensis can be incorporated into the eggplant’s genome and the plant will then secrete a protein that kills insects but is harmless to humans. Activists have organized protests with people dressed up like giant eggplants carrying placards about Indians being lab rats and companies putting poison into the food supply. Their cause is championed by environmentalist Vandana Shiva who suggests that GMO means God Move Over. She also claims that with genetically modified seeds giant corporations are trying to control all of agriculture. In fact the genetically modified eggplant seed is being donated for free by Monsanto and farmers will be allowed to propagate Bt eggplant using seeds from plants they have grown without having to pay any royalties. It is estimated that the technology could raise yields by about a third through controlling pests and go a long way towards solving the malnutriton and hunger problems that plague India and Bangladesh.

Of course hunger isn’t limited to these countries. In Africa cassava is a staple crop for some 250 million people. But two viruses can ravage the crop. One destroys leaves, the other, called brown streak virus, destroys the roots, something that isn’t evident until harvest time. These viruses are transmitted by the whitefly whose range is expanding due to climate change. Researchers are working on developing genetically modified strains of cassava that are immune to the brown streak virus. Of course, nobody is suggesting that genetic modification is the only answer to the whitefly problem. Planting rows of Tithonia diversifolia, a wild sunflower that whiteflies prefer, can also draw these pests away from cassava. Modern farming technology should be based on using the best combination of practices and in many cases that means the appropriate use of genetically modified seeds. Why deter farmers from using methods based on sound facts by promoting mythical fears?

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Climate Change

climate changeAs we get ready for winter here and watch news reports of unseasonable plummeting temperatures in some parts of North America, it is hard to be concerned about global warming. But climate change is here and it comes with baggage. Yes, there are some scientists who argue that humans are not responsible, and claim that we have experienced natural warming and cooling trends throughout history. They, however, are in the minority. The vast majority of climate change experts are convinced that the release of carbon dioxide and other greenhouse gases like methane and nitrous oxide are driving temperatures up with potentially a huge impact on wildlife, food production and the weather. Furthermore, when carbon dioxide dissolves in the oceans it forms carbonic acid which is detrimental to aquatic life.

The United Nations Intergovernmental Panel on Climate Change has just released its final report, summarizing 13 months of work, not by a handful of scientists, but by more than 800 experts. Natural forces have virtually nothing to do with the rising temperatures, they say. And those temperatures are rising with the chance that 2014 may turn out to be the warmest year on record. Where is all the carbon dioxide coming from? Burning of fossil fuels is the number one cause, followed by cement manufacture and “flaring,” the burning of gases that are byproducts of oil and gas production. Methane emissions, mostly from natural gas and animal agriculture are also having a large impact with further contribution from nitrous oxide released from nitrogen based fertilizer.

The Panel noted that glaciers are melting, Arctic sea ice is disappearing, sea level is rising, permafrost is thawing and that the number of hot days and nights are increasing. They warn that most plants, small mammals and ocean organisms cannot adapt fast enough to keep up with changes, and that a global temperature rise greater than 2 degrees Celsius will compromise food supplies everywhere. If nothing is done, they warn, the temperature is likely to rise by 4 degrees C by 2100.

The situation though, is not hopeless. Keeping greenhouse gases in the atmosphere below the equivalent of 450 parts per million of CO2 can prevent excessive warming. But how do we do this? There is no single measure that will solve the problem, but there are many possibilities. They include low-carbon electricity sources such as solar, tidal and wind power. Nuclear energy will have to play a role. Technical solutions for storing carbon dioxide need to be found. And there are small things we can all do. Change to low energy LED lights. Improve insulation. Turn down the heat and AC a notch. Car pool. Eat less. That’s right. Food has a huge environmental footprint. That chicken was raised in henhouses that were lit and climate controlled with electricity, was fed on corn grown with the aid of fertilizers and pesticides and ended up being packaged and trucked to stores. All of that requires energy input. And while you are at it, consider giving up bottled water and soft drinks. The energy expenditure to produce these is horrendous. Think about this as we wait for the first snowstorm to strike. It may be cold outside but climate change is still a hot topic.

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The oPhone

ophoneYour cell phone wakes you up in the morning. No big deal. You reach over to turn off the alarm, touch another button, and suddenly the smell of freshly brewed coffee wafts into your nose. But no point reaching for the cup, there isn’t one. The scent is drifting out from the phone! If you would rather wake up to the odour frying bacon and toast, that’s possible too. Welcome to the wonderful world of the “oPhone.” And we are not talking science fiction here; the oPhone already exists and will be hitting the market soon. Not only will you be able to entertain your nasal passages with a multitude of fragrances, you will also be able to send scent messages. Imagine irritating your friends back home with the scent of tropical fruit along with a picture of yourself swinging in a hammock and sipping a pina colada somewhere in the tropics. Of course your friends will have to be equipped with an oPhone.

So what makes this magic happen? A set of eight replaceable chips, each containing four “building-block scents” that can be dispensed in response to an electronic signal. The 32 basic smells can be combined to dispense a fantastic array of aromas. Select “meaty,” “cheesy” and “grilled toast,” and you’ll conjure up the odour of a cheeseburger. And of course you can experiment. Who knows what sort of a whiff you’ll get by pushing the “cocoa beans” and “meaty” buttons?

It sounds like the oPhone could be a lot of fun, but can this technology be put to some useful purpose? Maybe. You just finished dinner and there is that delectable dessert staring you in the face. You know you shouldn’t indulge, but it looks so good. Perhaps you’ll whip out your oPhone, push a button and the unpleasant smell of rotting meat will kill your appetite. There is even the possibility of diagnosing early Alzheimer’s disease. The inability to recognize certain scents has been linked with the early stage of this disease. And maybe the oPhone can even deal with the situation by helping with memory. Studies have shown that reading something while being exposed to a scent can lead to improved recall in the presence of the same scent. Trigger a smell from your phone as you put down your keys. When you want to find them again, push the button for the same scent and you’ll remember where you put them. Maybe. Of course this method won’t work to find a lost oPhone.

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