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When protein is not protein

Screen Shot 2015-03-30 at 11.42.01 AMYou need protein to build muscle. We have all heard that, probably as early as elementary school. And it is true. Muscle is mostly made of protein and its source is protein in the diet. But the route is not direct. Proteins are complex molecules composed of hundreds to thousands of amino acids linked together. When consumed, these chains are broken down into smaller fragments called peptides as well as into individual amino acids. Once absorbed into the bloodstream these are reassembled into proteins that include not only the structural parts of muscles but also enzymes and some hormones such as insulin. Of the twenty amino acids found in the body’s proteins, nine have to be supplied by the diet, the others can be made from other food components. The big question about proteins is how much do we need? Consume too little and the body suffers, consume too much and the extra is converted to fat.

It stands to reason that body size matters as well as level of activity. Muscle builders require more protein than couch potatoes. As a rough guide, people need at least half a gram per pound of body weight, recreational athletes need 0.7 grams and serious athletes about 0.9 grams per pound of body weight. Let’s take as an example a 170 pound male who works out quite regularly. His protein intake should be in the ballpark of 120 grams. That’s achievable by diet. A chicken breast has about 60 grams of protein, a hamburger 30, about the same as a serving of salmon, a couple of eggs 12, and two slices of cheese 15. Now, if someone is into serious body building, the needs can go up to 150-160 grams of protein a day. At this point adding some tofu with about 50 grams of protein per 100 grams might be in order. Or, there is always the possibility of using a protein supplement.

Protein supplements are big business, raking in about seven billion dollars a year world wide. They are sourced from milk or soy with a scoop generally containing about 40 grams of protein. But therein lies a problem. And it is a big enough issue to have resulted in law suits against the protein manufacturers. That’s because that protein powder may not be all protein thanks to something called “protein spiking” which involves using cheaper individual amino acids rather than proteins. For example, glycine, taurine and leucine are available at about one fifth the cost of proteins.

Now here is the scoop. A chemical analysis for proteins doesn’t really analyze for proteins but rather for nitrogen content. Since all proteins contain nitrogen, the amount of protein can be calculated from a nitrogen analysis. But the analysis does not distinguish between amino acids linked together in a chain, as in proteins, or individual acids all of which also contain nitrogen. In some cases a supposed 40 gram serving of protein may only deliver 20 grams, the rest being individual amino acids. What that means is that the ratio of amino acids in the supplement is not ideal for supplying what the body needs to build protein. While there is a degree of dishonest marketing here, there is no serious health consequence. Most people who supplement with protein powders, even if these are not everything they are made out to be, are probably taking in more protein than their body can possibly use.

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You Asked: Is there really a “dirty secret” about almonds?

Screen Shot 2015-03-30 at 11.35.07 AMAnytime you see an article that starts off with the heading “The Truth About….,” it’s a pretty safe bet that you will not get the truth. And so it is with an article circulating about almonds. “The Truth About Almonds: Almost No One Knows This Dirty Secret.” What is the “dirty secret?” That the almonds are treated with the fumigant propylene oxide to prevent contamination by salmonella bacteria. Salmonella infection is not pleasant to say the least. But people mostly associate it with contaminated eggs, not almonds. Where do the bacteria come from? Mostly fecal matter. Easy to see how eggs can be contaminated as they are laid. But almonds? Birds and insects can spread the bacterium after contacting fecal matter, but exposure may also be indirect through contaminated irrigation water. Salmonella bacteria can survive a long time even in dry conditions and dry heat treatment is not very effective at killing them. But fumigation with propylene oxide is. The nuts are placed in a chamber with liquid propylene oxide and the pressure is then reduced to allow quick evaporation of the liquid. The vapour destroys bacteria very effectively, preventing the possibility of food poisoning. There is no secret here. And nothing dirty is going on.

So what is the alarm all about? That propylene oxide is an animal carcinogen. That does not mean it is known to cause cancer in humans. And even if a substance is a human carcinogen, dosage still matters. While “carcinogen” is a frightening term, all it means is that the substance is capable of causing cancer in some animal at some dose. But there is a threshold effect. In rats no cancer can be found at any dose less than nine milligrams per kilogram of body weight, which has been established as the No Observed Adverse Effect Level (NOAEL). In other words at that dosage there is absolutely no problem detected.

Canada does not grow almonds so there has not been an application to allow the use of propylene oxide. This is not the same as it having been banned, as some alarmists claim. However, since Canada does import almonds that may have been treated with the chemical, the Pest Management Regulatory Agency has looked at the animal data and concluded that the maximum permissible residue is 300 parts per million. That is way below the NOAEL. And how much are almond eaters actually exposed to? The only way to know is to test for residues. That’s why the Canadian Food Inspection Agency tested over a thousand samples of spices, herbs, cocoa powder and nuts, including almonds. Guess what they found? No residue at all! So there is no reason to be concerned about propylene oxide in almonds because it isn’t there. And that is the truth.

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Want to keep Alzheimer’s disease at bay? Who wouldn’t? So let’s surf the web! Keep in mind that almost every study encountered is riddled with “ifs” and “maybes.”

Screen Shot 2015-03-24 at 9.10.52 PMSticking to the Mediterranean diet – low in meat and dairy products, high in fruits, vegetables, legumes, cereals and fish – would seem to be a good start. A study of close to 500 seniors with mild cognitive impairment showed a reduced risk of developing Alzheimer’s with adherence to the Mediterranean diet. Eating fish is an important feature, with studies showing that people with higher blood levels of omega-3 fatty acids tend to have larger brain volumes in old age. It seems fish oil protects the brain’s hippocampus region, the area where shrinkage is associated with dementia.

But watch how you cook your meals. Grilling, frying or broiling produces “advanced glycation end products,” which have been linked to inflammation, insulin resistance and Alzheimer’s disease. And watch that sugar intake. A study of some 900 subjects with no cognitive problems found that within four years, 200 began to show mild cognitive impairment. Those with the highest sugar intake were 1.5 times more likely to have memory problems than those with the lowest intake. Diets containing walnuts as well as strawberry or blueberry extracts were found to reverse several parameters of brain aging, as well as age-related motor and cognitive deficits. As long as you are an aging rat.

Might not be a bad idea to add a little Indian flavour to the diet in the form of turmeric, a common spice in curry. Curcumin, its major component, has been linked with slower cognitive decline and reduced amyloid beta plaques, one of the major causes of Alzheimer’s disease. Grape seed extract appears to have the same effect, at least in mice. People with Alzheimer’s tend to have lower vitamin D than those without the disease, and better cognitive test results have been linked with higher vitamin D levels. A supplement may be in order.

People who drink three to five cups of coffee a day in their midlife years have a 65-per-cent lower chance of developing dementia and Alzheimer’s disease compared with those who drink little coffee. Green tea will do as well since its epigallocatechin-3-gallate content has been shown to prevent the buildup of beta-amyloid aggregates, at least in lab experiments. In non-smoking women, moderate alcohol consumption reduces the risk of Alzheimer’s. And consider fruit juices. People drinking them three or more times per week were 76 per cent less likely to develop Alzheimer’s than those who drank less than one serving per week. Pomegranate juice may be particularly beneficial.

Instead of thinking about what to eat or drink, perhaps we should think about infusing protective factors directly into our blood. Studies have shown that a transfusion of young mouse blood into older animals can improve cognition. Focus is on a protein in blood plasma called “growth differentiation factor 11 (GDF11)” that declines with age both in mice and in humans. Drinking young blood won’t do.

You want to make sure you breathe clean air. Women who live in areas with the worst quality air score perform more poorly on tests of memory and thinking than those who live in cleaner areas. On the other hand, there is a correlation between strict hygiene and sanitation methods as practiced in wealthy countries and the prevalence of Alzheimer’s disease. The “hygiene hypothesis” is gaining traction when it comes to allergies and asthma, with the theory being that exposure to bacteria, viruses and worms early in life primes the development of a healthy immune system. Some researchers suggest that the deposition of proteins in the nervous system, one of the hallmarks of Alzheimer’s, is a result of an immune system gone astray.

And remember to brush your teeth. A study that looked at 100 sets of twins, one with Alzheimer’s and the other unaffected, found that the twin with dementia was four times more likely to have had mid-life gum disease. Playing chess, reading newspapers and engaging the brain in other tasks can significantly reduce the risk of Alzheimer’s in later life, as can physical exercise. Be conscientious. Subjects who enthusiastically agreed with statements such as: “I work hard to accomplish my goals,” “I strive for excellence in everything I do,” “I keep my belongings clean and neat” and “I’m pretty good about pacing myself so as to get things done on time,” were less likely to develop Alzheimer’s disease.

Finally, I came across a paper I really liked. A brain scan study at the University of California concluded that surfing the web increases brain activity more than reading a book. What can I say? Maybe.

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Fear of Fries

McDonald'sI’ve been repeatedly asked about the “dangers” of McDonald’s fries. First a couple of disclaimers. I am not particularly fond of McDonald’s French fries, and I am a fan of Michael Pollan’s writings on food and nutrition, particularly his classic book “The Omnivore’s Dilemma” in which he summarizes his 400 or so pages with the advice to “eat foods mainly of plant origin and don’t eat too much.” He is also a fan of home cooked meals, which is great, but sometimes his attacks on processed foods are overzealous.

In a widely circulated video Pollan blasts McDonald’s not for any nutritional shortcomings of its fries but for accepting only potatoes of a certain size and shape and shunning any with blemishes caused by aphids. That, Pollan suggests, forces farmers to use pesticides such as Monitor (methamidophos) which he deems to be particularly dangerous. Indeed he points out that this chemical “is so toxic that farmers who grow these potatoes in Idaho won’t venture outside and into their fields for five days after they spray.” He goes on to say that the potatoes have to be stored in giant sheds for six weeks so they have time to off gas all the chemicals in them. The video had quite an impact, triggering headlines like “watch this video and you will never eat McDonald’s French fries again.” The issue needs a closer look.

Yes, McDonald’s likes it’s potatoes to be of a certain size so that the fries are long and reach out in an appealing fashion from their container. It doesn’t mean that other potatoes are wasted. McDonald’s buys its fries from distributors who select the appropriate ones for the company and sell the others elsewhere. It is also true that McDonald’s does not want potatoes that are affected by “net necrosis,” a viral infection spread by aphids. Nobody wants to eat potatoes permeated with black streaks like a net. As far as farmers not wanting to go out into the fields, well, that is standard protocol after spraying with any pesticide. Intervals that have to be respected after spraying any pesticide are established by regulatory agencies such as the U.S. Environmental Protection Agency.

Pollan’s notion about storing the potatoes for sixty days to off gas toxins is pure nonsense. Potatoes are routinely stored in large atmosphere controlled sheds because they have to be available year round. In any case, crops are monitored for pesticide residues and all such found on potatoes are way below established tolerance levels. There may be reasons to stay away from McDonald’s fries, but not because of any highlighted in this unnecessarily alarmist video. The fat content, the high glycemic index, the amount of salt added and maybe some of the compounds formed during high temperature frying are reason enough to make fries an occasional treat. And as a final point, the pesticide being talked about, methamidophos, has not been used since 2009.

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You Asked: Should we worry about arsenic in wine?

wineA story about arsenic-laced wine is panicking a lot of people. It’s all about a lawsuit brought against the producers of some wines claiming they contain unsafe amounts of arsenic. As far as I can tell, the lawsuit is an attempt at money grab by a company that performs analyses for substances such as arsenic in beverages. The idea seems to be to cash in on the public fear generated by the lawsuit. People will clamor for the testing of wines, a service the company provides. Any story about arsenic, the fabled “widow maker,” is guaranteed to trigger publicity. Witness Dr. Oz’s shows on arsenic in apple juice and wine.

According to the lawsuit, some cheaper wines contain up to five times as much arsenic as is allowed in tap water, which is 10 ppb. Anything that grows in soil will have some arsenic because arsenic compounds occur naturally. The 10 ppb limit in water has a large safety factor built in, but more importantly, people do not drink as much wine as water. And if they do, they need to worry about the alcohol content far more than about the arsenic content.

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A cranky homeopath

ADHDThe Toronto Star published a letter from a physician in BC who was critical of my attacks on homeopathy. Below is his letter as well as my response.

Published on Mon Mar 16 2015
Re: Scientists skeptical of study on ADHD care, March 6

As a medical doctor, I use homeopathy on a daily basis to fill in gaps or improve on the conventional therapies I also use in family practice. There is no doubt that homeopathy works – even in children and in skeptical patients that are willing to give it a try (particularly if they have tried everything else without benefit); sometime even in patients’ pets. Sure, good interaction and placebo play a role, just as in any therapeutic encounter, but that does not explain the results I observe.When a group of “top” scientists declare that there is no evidence to support homeopathy, you cannot but wonder at their agenda. In fact, there have been several meta-analyses and governmental assessments that show homeopathy is effective (BMJ 1991, Lancet 1997, Eur J. Clin Pharmacology 2000, Swiss Federal Office for Public Health 2006).

There are numerous positive trials, many of fair to high quality. Medical doctors around the world have accepted homeopathy based on sound evidence and the personal experience that confirms it. In Belgium, for example, 4000 doctors prescribe homeopathic medicines routinely. Homeopathy is inexpensive, convenient, integrates well with conventional medicine, and patient satisfaction and safety are excellent. It is included in the national health schemes of Great Britain, France, Switzerland, Brazil, Mexico, India and many other countries. The recent discovery of nanoparticles in homeopathic ultra-dilutions has undermined the “implausibility argument” or “I can’t understand how it works, therefore it can’t work.” This type of flat-earth thinking is not helpful in promoting better healthcare and has no place in medical practice or research.

The main reason pseudo-scientists become quack-busters and criticize therapies such as homeopathy is fear. Perceived as a threat to their world-view, they use the labels “unscientific” or “implausible” to defend themselves against the barbarians at the gate. It is not really an issue of evidence or science. It’s a subconscious defense mechanism that cannot be overcome, even if the research is piled up to the ceiling. It may be disguised as defending the public, but as Shakespeare says: “The lady doth protest too much.” The potential benefits of homeopathy demand research such as Dr. Heather Boon’s ADHD study at University of Toronto, and we should not let fixed thinkers get in the way of progress in medicine. In fact, the criticism here should be levelled at McGill University for permitting its Office for Science and Society to exist and Dr. Joe Schwarcz to continue to “interpret science for the public.”
Dr. Stephen Malthouse, past president, Canadian Complementary Medical Association, Denman Island, B.C.

Dr. Stephen Malthouse’s ungracious letter requires a response. “There is no doubt that homeopathy works,” he maintains. That may be his opinion but not that of the vast majority of the scientific community. That point was effectively driven home last week by a report from Australia’ s National Health and Medical Research Council that concluded “there is no good quality evidence to support the claim that homeopathy is effective in treating health conditions.” It was the most damning analysis of homeopathy ever compiled.

Dr. Malthouse trots out the tired old refrain that a discovery of some anomalous property of water undermines the argument that homeopathy is implausible. Nobody has ever maintained that homeopathy is implausible because water cannot have anomalous properties. That is a straw man argument if there ever were one. Homeopathy is implausible because it is based on the precept of ghostly images supposedly imparted to water by sequential dilutions and succusions having a healing effect.

Dr. Malthouse goes on to suggest that “it is not really an issue of evidence or science.” It most assuredly is. The science of homeopathy is non-existent, just like the molecules it is supposedly based upon. And the evidence is in for anyone who cares to look at the 225 well-designed studies that formed the basis of the Australian report. As far as Dr. Malthouse’s boorish remark that the McGill Office for Science and Society should not exist, his letter is a shining example of why there is a continuing need to interpret science for the public in an evidence-based fashion, which is exactly why the Office was established.

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The Food Babe doesn’t take well to criticism

vani hariOur pal the Food Babe seems to have a very thin skin. She responded on her website to the article about her in the New York Times in which I was quoted along with a number of her other critics. It is true that I said she gets on talk shows because she is pleasant to look at. Isn’t that a compliment? She says that is “sexist.” And this is from a woman who calls herself “The Food Babe.” Is she serious?

Yes I am on the editorial board of ACCN, the magazine of the Canadian Chemical Society and in fact write a regular column for the magazine. Vani thinks that the Society is some sort of industrial lobby. It is nothing of the sort. It is the academic voice of Canadian chemistry. Just another example of her being totally out of touch with how the scientific world functions. Her comment that I never met a chemical I didn’t like is so silly that it is unworthy of a rebuttal. I never called her “that stupid woman,” in public, but she has said many things that could invite such a comment. Here is a winner: “There is just no acceptable level of any chemical to ingest, ever.” As far as funding from the Council of Biotechnology Information goes, twelve years ago we did receive support for student interns, none of whose work had anything to do with biotechnology. Funny that a funding issue should be brought up by someone who profits greatly from items she pushes.

Yes, I did bring to students’ attention the fact that Vani blocks anyone from her Facebook page who asks about her credentials. They found this such an affront to science that they checked it out themselves and ended up being blocked. Isn’t it ridiculous that someone whose knowledge about chemistry goes no further than advising people that if they can’t pronounce it, they shouldn’t be eating it, ends up being interviewed by USA Today about the difference between sugar and high fructose corn syrup?

It is also true that I have questioned her mental abilities. How could I not when she wrote a piece about believing that the properties of water were affected by a label on the bottle that had either loving or hateful words written on it. Let me also mention that on numerous occasions I invited her to be a guest on my radio show to air her views and she refused. I stand by my opinion of her. She is a possibly well-meaning, scientifically illiterate publicity hound who bullies companies to conform to her mostly ignorant demands. As far as being addicted goes, the only thing I’m addicted to is proper evidence-based science. And the Food Babe most assuredly does not fall into that category.

Unfortunately I can’t put these comments on her Facebook page from where I have been banned. Neither can I put them on her website where comments have been closed. It seems the Babe can dish it out but can’t take it.

 NY Times:

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VegeGreens products’ unfounded claims hide behind great marketing

vegegreenI 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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