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The Fat Conundrum

fatButter or margarine? Olive oil or canola oil? Low fat diets or high fat diets? You would think that after literally thousands of studies we would have some straight forward answers about the effect of fat on our health. But such is not the case. There is pretty solid evidence that saturated fats raise blood cholesterol. There is also solid evidence that high levels of blood cholesterol are a risk factor for heart disease. But then there is the conundrum. Studies have not been able to show that saturated fats raise the risk of heart disease. How is that to be explained?

There are several ways that the relationship between fat intake and health can be studied. Animals, rodents mostly, can be fed diets containing different fats and their health can be monitored. This is close to useless. The natural diet of these animals is very different from that of humans, as is their physiology. Also the manipulated dietary changes are much greater than that seen in human diets. Of greater significance are observational studies in which people are asked to fill out food frequency questionnaires from which the fat components of the diet are calculated. But people are notoriously unreliable in remembering what they have eaten and in judging amounts. Somewhat better are studies that actually measure blood levels of fatty acids which are a reflection of diet, but these do not determine the source of the fats. For example, saturated fats from meat may not have the same effect on health as those from dairy because both meat and dairy contains numerous other compounds that can have an impact. Then there is the issue that not all saturated fats are created equal and their effect may depend on the number of carbon atoms in the molecule. So-called medium chain fats, as found in coconut fat, may have a different impact than the longer chain saturated fats in chocolate, which may yet be different from those found in meat or dairy. Add to this the fact that diets also contain a variety of monounsaturated and polyunsaturated fats, which again can have a different effect on health than saturated fats, and we have an increasingly complex picture. Of course, fats are not eaten in isolation, they are part of a diet. If someone cuts down on fatty foods, they have to be replaced with something. Unfortunately, the replacement often turns out to be loaded with refined carbohydrates, particularly sugar, which pose a cardiovascular risk themselves. So in such a case, cutting back on saturated fats would not lead to a reduction in cardiovascular risk.

Where does this leave us? While studies examining saturated fats in isolation have not been able to link them to heart disease, there is plenty of evidence that replacing saturated fats with polyunsaturated ones leads to lower cholesterol levels and a reduction in the risk of cardiovascular disease. So if saturated fats are to be replaced, they should be replaced by unsaturated fats rather than by carbohydrates. As they are in the Mediterranean diet, which is heart healthy despite being high in fat. But the fat comes mostly from nuts, seeds and olive oil, not meat or butter.

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Hormones in cattle

A&WThose ads from A&W claiming that their beef is raised without hormones or steroids are popping up on TV with annoying frequency. The intent obviously is to suggest that this meat is somehow safer than competitors’ brands. There is absolutely no evidence for this. The growth promoters used in cattle, usually released from capsules implanted in the ear, are regulated just like drugs intended for human use and residues are carefully monitored. The use of growth promoters results in better conversion of feed to muscle, meaning that meat can be produced more economically. Six such substances are approved. Three are natural hormones (testosterone, estradiol, and progesterone) and three are chemically similar synthetic hormones (melengestrol acetate, trenbolone acetate and zeranol). All of these, except for zeranol, are chemically classified as steroids. Zeranol is extracted from a mould found on corn. That should please the “natural” crowd who assume that natural substances are always better than syhthetics. Zeranol is mildly estrogenic, with 25% of the estrogenic activity of natural estrogens at the same dose level. The fact is that hormonal activity in treated beef sold for consumption is indistinguishable from that in non-treated beef. And remember that meat contains hormones naturally produced by the animal in far greater amounts than any residue from growth promoters. Furthermore, far, far more natural estrogen is produced by the human body on a daily basis than that consumed in meat from treated cattle. For example, a woman produces about 500,000 nanograms of estrogen a day (40 times that much when pregnant) while the amount in a quarter pound hamburger is about 2 nanograms! The estrogenic activity of milk, butter or eggs is much greater than that of meat from implanted cattle and soy products are millions of times more estrogenic. A&W’s suggestion that their beef is healthier than other beef is not supported by science. It is a marketing gimmick. Eating an A&W burger is no better in terms of health than any other burger. Another way of putting this is that burgers made from cattle raised without hormone implants are just as suspect nutritionally as any other burger. And that suspicion involves an increased risk of cancer in carnivore populations when compared with vegetarians. Of course that doesn’t mean hamburgers can’t be a part of a healthy diet, but they shouldn’t be a staple. I do occasionally eat an A&W burger, when I can’t find an open Harvey’s. And I certainly do not give any consideration to whether the meat comes from implanted cattle or not.

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Whole grains and protein, part of a complete breakfast

oatmeal“Eat Your Oatmeal! Study Finds That A Bowl A Day May Keep The Grim Reaper Away,” screams a headline reporting on a study by researchers at Harvard University.

Somewhat overly optimistic, given that there is pretty good evidence that the Reaper eventually gets us no matter what we have for breakfast. But according to this study, we may be able to put off his inevitable visit, even without oatmeal. The study did not investigate oatmeal per se, rather it dealt with the consumption of whole grains.

The Nurses Health Study and the Health Professionals Follow-Up study that followed over 110,000 subjects for 25 years have provided Walter Willett and colleagues at Harvard with a wealth of information. Initially free of heart disease, the participants filled out periodic questionnaires about diet and various lifestyle factors. Close to 27,000 died during the study, and after adjusting for confounders such as age, smoking, physical activity and body mass index, the researchers concluded that higher whole grain intake was associated with lower mortality. And the effect wasn’t marginal.

Total mortality was reduced by 5 per cent and deaths from heart disease by 9 per cent during the 25 years spanned by the study. Since bran intake had a similar protective effect and cereal germ intake did not, the results imply that the benefits seen can be attributed to whole grains. And how much do we have to eat to see a reduction in mortality? About 30 grams, which is not a lot. That’s roughly the common serving size for whole grain cereals.

So how does oatmeal fit into this? It’s just an example of a whole grain, perhaps the reporter’s favourite. Although this study did not look at oats in particular, many others have, because oats contain beta-glucan, a form of soluble fibre that has been shown to lower cholesterol. Indeed, when Chinese researchers gave subjects with moderately elevated cholesterol either 100 grams of instant oat cereal or 100 grams of wheat flour-based noodles for six weeks, they found that total cholesterol and LDL cholesterol decreased by seven and nine per cent respectively, which is significant. An added benefit was a decrease in waist circumference of about 1.3 centimetres (half an inch), while the noodle eaters slightly increased their waist circumference. The researchers concluded that increased consumption of whole grains, including oats, should be encouraged.

I’m all for that. Steel-cut oatmeal, or oat bran, with berries or other fruits, along with some Greek yogurt is my favourite for starting off the day. Indeed, the adage that breakfast is the most important meal of the day actually has some traction. It turns out that what is eaten for breakfast has an effect on the ups and downs of blood glucose for the rest of the day. And that is important because fluctuations in blood glucose stress the pancreas and increase the chance of developing diabetes. Furthermore, a skimpy breakfast not only reduces energy levels throughout the morning, it increases the chance of overeating at lunch.

Unfortunately, some people think that skipping breakfast is helpful for weight loss. After all, no breakfast means no calories. But studies show that this is not an effective strategy. Breakfast skippers are more prone to “Night Eating Syndrome,” and moderately overweight women have been shown to lose more weight when they consume 70 per cent of their daily calories before noon instead of the afternoon or evening. To further boost the arguments for a good breakfast, we can look at studies that show people who do not eat breakfast have a higher risk of developing heart disease and diabetes. They also may be less creative and slower at processing information in the morning.

Now that we know how important breakfast is, we can get down to the nuts and bolts of what it should be. I like oatmeal, fruit and yogurt, but there’s no magic formula. First, breakfast should not be meagre: 400-500 calories is a ballpark figure. But what we don’t want is a lot of sugar. No more than about 10 grams. What we do want is whole grains and some protein. Roughly 25-35 grams of protein in the morning stabilizes blood glucose, increases satiety and reduces calorie consumption during the rest of the day.

While cereals that are low in sugar are available, they generally contain only a few grams of protein. Plain Greek yogurt is a good choice for increasing protein intake because a serving has 20-25 grams and generally less than 10 grams of sugar. It is available in a no-fat version. Some whole grain toast with almond butter, and you’ve got a breakfast that nutritional scientists would drool over.

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Pills for the Brain

Screen Shot 2015-01-15 at 9.11.26 AMPop this pill and improve your memory. Swallow that one and reduce your cognitive decline. We see ads for such products all the time and I suspect they will increase as the baby boomers reach senior citizenhood. The most popular brain boosting supplements are fish oil pills and they are also probably the best studied ones. The results are not encouraging. When all the studies are pooled, we are left with the possibility of a barely significant improvement in recalling lists of words soon after they have been learned, but the effect does not last. Extracts of the ginkgo biloba tree are also popular, and here the prospects are even dimmer. There is no impact on memory, despite claims of increased circulation in the brain. And ginkgo can interfere with the action of anticoagulants and has also been shown to be an animal carcinogen.

B vitamins are also sold with claims of enhancing memory, usually rationalized by their reduction of homocysteine, a chemical in the blood that may affect circulation in the brain. No benefits from B vitamin intake have been demonstrated when it comes to memory or cognitive function except in the case of people who have high homocysteine levels due to a diet that is very low in B vitamins. There is some concern that folic acid, one of the B vitamins, may spur the growth of polyps in the colon at doses greater than 800 micrograms a day. Phosphatidyl serine is a natural component of nerve cell membranes and its promoters argue that a deficiency leads to impaired communication between nerve cells which in turn impairs cognitive function. Sounds reasonable, except that proper controlled trials have come up empty. The same goes for vinpocetine, a compound originally isolated from the lesser periwinkle plant by Hungarian chemist Csaba Szantay in 1975. It is widely used in Europe to treat strokes and memory problems with claims of increased circulation to the brain. It does indeed increase circulation, much like ginkgo, but there is no compelling evidence for memory improvement.

People with failing memory and worried about Alzheimer’s disease are sometimes seduced by advertisements for Huperzine A, extracted from a type of moss. Some studies have shown that it increases levels of acetylcholine in the brain, a chemical that is in short supply in Alzheimer’s. But despite increasing acetylcholine, aside from a few questionable studies in China, there is no evidence that it improves memory. Unfortunately when it comes to memory pills, they are best forgotten. There is, however, hope that a nasal spray containing insulin can increase the absorption of glucose into brain cells and improve cognitive function. But in the meantime, the best bet to maintain good brain function is to monitor blood glucose and blood pressure, eat a diet rich in fruits, vegetables and whole grains, and low in simple carbs and saturated fat. And don’t forget that physical exercise also exercises your brain.

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Snake Bitten

boomslangNot many people have heard of boomslang. That’s not surprising because these venomous tree snakes are a super shy and non-aggressive species native to Sub-Saharan Africa. These snakes exhibit sexual dimorphism therefore it is easy to distinguish between genders. One of the most obvious morphological differences between genders is that females are brown in color while males are usually bright colors such as green, yellow or pinkish red. Boomslang snakes have strikingly large eyes and juvenile boomslangs are known for their beautiful iridescent green eyes.

Because boomslang snakes are ‘rear-fanged’ it is extremely unlikely to be bitten by this snake.  One has to be very unlucky! In order for the boomslang snake to inject its venom on its prey, it would have to open its mouth extremely wide, scientifically speaking, to at least 170 degrees. Because of this, boomslang snakes have been dubbed “harmless.” But it wasn’t until 1957 that this was proved not to be the case.

In 1957, a juvenile boomslang snake raised in captivity at Chicago’s Lincoln Park Zoo bit well-known herpetologist Karl Schmidt.  The bite was minor, just a single fang on his thumb! But that was enough to kill Karl Schmidt.

Karl Schmidt’s death revolutionized the scientific world. The venom of the boomslang snake was analyzed and it was revealed that boomslang venom is highly potent and primarily is a hemotoxin.

Hemotoxins are toxins that destroy red blood cells, disrupt blood clotting and can also cause organ and tissue damage. Because boomslang venom is a hemotoxin it’s not surprising that it can lead to major brain and muscle hemorrhage. But the venom also causes other symptoms like nausea, headaches and sleepiness. Perhaps what is most surprising is that this venom has the ability to make the victim bleed from every possible orifice. It is not uncommon for blood to seep out of the victim from the gums, nostrils, urine, saliva, stools, vomit and even through the tiniest of cuts. This is extremely unfortunate because the victim will continue to bleed until death and death from internal bleeding is a slow and lingering process that can take anywhere from three to five days.

One of the issues with boomslang venom is that symptoms emerge only several hours after being bitten. Because the venom is not fast acting, victims may not realize that they are at serious risk and require immediate medical assistance. Although records show that less than ten people have died from boomslang bites worldwide, this ought to not be taken lightly.  Death came swiftly for Karl Schmidt, as he was found dead 24 hours later in his home from respiratory arrest and severe brain hemorrhaging. If Schmidt had known about the anti-venom his life might have been spared. It is imperative to act quickly otherwise Africa’s most venomous snake might have the last laugh.

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Dr. Oz’s “Two Day Holiday Detox” should be flushed

OScreen Shot 2015-01-07 at 5.50.08 PMne would think that producers of the Dr. Oz show would pay at least a little attention to the widely publicized study that appeared in the British Medical Journal examining the health recommendations made on medical talk shows. The researchers looked at eighty recommendations made on the Oz Show and found that evidence supported 46%, contradicted 15%, and no evidence was found for 39%. Not exactly a stellar performance. Yet on the heels of the stinging paper, what does the Dr. Oz Show come up with? A segment that has no supportive evidence whatsoever.

“Dr. Oz’s Two Day Holiday Detox” promises a “quick fix to offset the damage from holiday eating.” “It can’t miss,” quips Oz. Oh yes it can. The whole notion of “detox” is nonsense and the idea that you can eat whatever you want and then repair the damage with two days of feasting on melon juice, coconut water, oatmeal, lentil soup, cabbage salad and chocolate tea is absurd. But according to Oz, this diet will release retained water, rebalance blood sugar, remove “fat promoting toxins” and recharge your metabolism. What evidence is provided? A couple of meaningless but entertaining demonstrations. To show how the melon juice and oatmeal reduce bloating, Oz and a guest spray water at a TV screen showing a bloated silhouette which then magically transforms into a svelte figure. If only it were that easy. As far as oatmeal goes, I think it does make for a great breakfast. But there is not a single reference listed in PubMed for oatmeal having a diuretic effect.

Next, Oz presents a long rope and begins to make waves with it to explain how blood sugar can fluctuate during holiday feasts. Then pulling the rope taut supposedly indicates how lentil soup, being of low glycemic index, straightens out blood sugar fluctuations. Eating low glycemic index foods does result in less fluctuation of blood glucose, but it doesn’t undo any previous damage that such fluctuations may have caused by having gorged on eggnog. What about cabbage salad removing “fat promoting toxins,” that according to Oz are found in high sugar junk food? I would like to know what these unnamed fat-promoting toxins are. The only info we are given is a graphic with some sort of muck stuck in the colon, supposedly the “toxins.” Cabbage, because of its fiber content, acts as a laxative, which is the argument used for it “flushing out the toxins.” Nothing wrong with eating cabbage, but the idea that it flushes out toxins deserves to be flushed.

Finally, for people who have overindulged in marshmallow cookies, Oz recommends chocolate tea for “boosting metabolism,” but curiously points out that it has very little caffeine, a substance that may actually boost metabolism. There is nothing in the scientific literature that lends any significant support to specific foods or beverages boosting metabolism in any practical fashion. Aside from making recommendations without any evidential basis, Oz’s real crime here is to offer a magical solution to overindulgence instead of emphasizing the need for a proper well-balanced diet and exercise year-round.

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When “Mayo” isn’t “mayonnaise”

Screen Shot 2014-12-30 at 6.07.59 PMSo, when is mayonnaise not mayonnaise? If you ask Unilever, producers of “Hellman’s Real Mayonnaise”, which is the market leader in the 11.3 billion dollar a year global mayonnaise industry, it’s when the product contains no eggs. The Federal Food and Drug Administration agrees, defining “mayonnaise” as a condiment that must contain a specific amount of vegetable oil and egg yolk. But what if you just shorten the name and call it “Just Mayo?” Does it still have to contain eggs? No, says Josh Tetrick of Hampton Creek, maker of a new-fangled spread that advertises itself as being healthier, more environmentally friendly and more humane than “real mayonnaise” The term “mayo” is not defined, Tetrick maintains, and he says he does not sell his product as mayonnaise. “It’s Just Mayo.” Apparently though, consumers do not see the difference. A marketing professor hired by Unilever to survey consumers found in an online survey that more than half thought Just Mayo was mayonnaise judging by the label.

What about the promotional claims that Hampton Creek makes? The “more humane” refers to the way egg-laying chickens are raised in small cages. True, the peas that are grown to produce the extract used to emulsify the oil and vinegar in Just Mayo have a peaceful life, and presumably do not suffer when their pods are torn limb from limb. The environmental friendliness is based on the ratio of energy input to food energy output for eggs being about 39-to-1, whereas Just mayo’s plant ingredients that replace eggs weigh in at a ratio 2-to-1. That saving seems to have been enough to convince Bill Gates to lend his support to “Just Mayo.”

Hampton Creek may be on firm footing when it comes to promoting the benefits of “no eggs” in terms of environmental foot print, but there is also the implication of health benefits. Here they are trampling in mud. The calorie count in Just Mayo is identical to that in Hellman’s “real mayonnaise,” both containing 90 calories per serving, all of which comes from the 10 grams of fat found in each serving. The 5 milligrams of cholesterol in the real mayo is inconsequential. Curiously, Just Mayo lists its protein content as zero, yet its promotional material describes how the company’s biochemists have investigated numerous plants to come up with a protein that can rival egg yolk as an emulsifier. Obviously not much of this protein is needed in the product since it is not listed on the label.

Another curiosity is the presence of organic sugar in the list of ingredients, yet the carbohydrate count on the label is given as zero. Hampton Creek also makes a big deal out of its non-GMO certification, a reference to the canola oil, its main ingredient. This is a marketing gimmick aimed to please the “organic” crowd. There is no chemical difference between conventional canola oil and that extracted from plants containing a gene that makes them resistant to herbicides. Eventually the success or failure of Just Mayo will rest on its taste. People may talk environmental stewardship, but they eat taste. Whether Just Mayo will turn out to be just as tasty as real mayo remains to be determined. But keep in mind that any food that derives all its calories from fat should be consumed in a limited fashion.

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You Asked: Can the “Smart Drinking Pill” reduce the risk of drinking alcohol?

Screen Shot 2014-12-30 at 6.05.47 PMThe jury is out on whether drinking small amounts of alcohol is beneficial or detrimental. Some studies suggest a drink a day may be good for the heart. On the other hand, alcohol is a known carcinogen linked to cancers of the mouth, esophagus and breast. But when it comes to consuming excessive amounts of alcohol, the verdict is in. Liver damage, hypertension, neuropathies, seizures, gout, pancreatitis and dementia are all possible consequences of too much alcohol. And then of course there is the problem of impaired driving and life destruction due to addiction.
Liver damage is a major concern and one that is addressed by the makers of the “Smart Drinking Pill.” They claim that the mixture of plant extracts, vitamins and minerals in the pill can prevent liver damage and present an “option other than to quit drinking.” Milk thistle, artichoke extract and dandelion root are backed by some evidence in terms of offering liver protection, and the vitamins may be of some help given that people who drink a lot tend to have depleted levels. Liver function is generally determined by measuring blood levels of two enzymes, namely aspartate transaminase (AST) and alanine transaminase (ALT) that are produced by the liver as it detoxifies foreign substances. High levels indicate the liver has to work excessively and is prone to damage.
The single piece of evidence provided by makers of “The Smart Drinking Pill” is a blood test of a single individual whose AST and ALT went from high to normal after two months on the pill with no change in alcohol consumption. And what was this individual’s consumption? Thirty to forty drinks a week! Suggesting that reduction of the liver enzymes means that you can “responsibly enjoy alcohol without having to suffer the negative health consequences” is absolutely foolish. At that level of consumption there are many other risks than liver damage. If someone is drinking that quantity of alcohol the only smart thing to do is to cut back. The Smart Drinking Pill just encourages unhealthy behaviour.

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