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Food Babe Lesson #2

vani hariI’m not sure my chemistry lesson for the Food Babe got through to her but many of you said that I should keep up the effort to teach her some science. Others said that it was like trying to teach an ant to crawl up a Teflon wall. Let’s give it another shot.

Vani, you posted a recipe for a smoothie, which is fine, but it was accompanied by this introduction:

“I include smoothie recipes like this as a regular part of this program because it’s one of the best ways to get greens in your diet, provide your body a rich source of chlorophyll on a daily basis, and ultimately is one of the key actions you can take to keep your body in an alkaline state to avoid disease!”

Chlorophyll is one of the most important compounds in the world because without it plants cannot photosynthesize and without plants there is no life. But humans are not plants; we do not photosynthesize and have no need for chlorophyll. Yes, there are some claims that chlorophyll in the diet can prevent some carcinogens, such as produced by high cooking temperatures, but there is no proper scientific evidence that this is so. But that is a minor point in comparison to your call for keeping the body in an alkaline state.

Alkalizing” the body is a nonsensical concept. The human body carefully maintains the pH of blood at about 7.35, which is slightly alkaline, or basic. This is also the pH of the cells in all our organs that depend on the blood supply for their nourishment. Should the pH drop below 7 or exceed 7.7 we are looking at a potentially catastrophic situation. Luckily, our blood constitutes a buffered system, meaning that any variation of pH is immediately compensated for. Should there be an increase in acids entering the bloodstream, we immediately start exhaling more carbon dioxide, which then reduces acidity. Should the blood start to alkalize, the lungs retain more carbon dioxide, which dissolves to form carbonic acid while the kidneys eliminate basic bicarbonate.

What all this means is that the pH of the blood cannot be altered by changing the diet. A change in diet can certainly alter the acidity of the urine but that is unrelated to the pH of the blood. Breads, cereals, eggs, fish, meat, poultry can acidify the urine while most fruits and vegetables tend to make it more alkaline. The idea of monitoring the pH of the urine to achieve optimal health by “balancing” the body’s acidity is senseless. Is it possible that some people feel better by making their urine more alkaline? That’s possible. If they switch from a heavy meat and cereal diet to one that features more fruits and vegetables they may feel better. But this has nothing to do with balancing the body’s pH.

 

Joe Schwarcz

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!

Joe Schwarcz

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.

Joe Schwarcz

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.

Joe Schwarcz

You Asked: Is fish really brain food?

brain foodIs fish really brain food? P.G. Wodehouse certainly thought so. In his wonderful “Jeeves” stories, Bertie Wooster encourages his brainy butler to eat more fish whenever a particularly challenging problem arises. But to what extent does fiction mirror real life? One can make a theoretical case for fish consumption based on the fact that docosahexaenoic acid, or DHA, the famous omega-3 fat in fish, is the main component of brain cell membranes, and that communication between brain cells is a function of the integrity of these membranes.

There is actually some experimental evidence to support a link between fish consumption and brain health. Infants born to mothers who consumed more fish during pregnancy have been shown to have improved verbal intelligence, better fine motor skills and pro-social behavior. A study has also correlated fish intake during pregnancy with IQ in 8-year old children. It is likely that these effects are due to increased blood levels of DHA in the offspring, but as is generally the case, the scenario is complicated. When blood is drawn from umbilical cords, it turns out that the concentration of the various fatty acids depends on the genetics both of the mother and the baby. In other words, depending on genotypes, an infant may benefit more or less from fish in the mom’s diet.

What about brain function at the other extreme of life, senior citizens? To get some insight here, researchers examined MRI brain scans of 260 individuals over the age of 65 who had normal cognitive function looking for differences associated with fish consumption as determined by dietary surveys. Subjects who ate baked or broiled but not fried fish every week had larger grey matter volumes in the areas of the brain responsible for memory and cognition. Interesting, but there was no determination as to whether these increased volumes translated to any change in brain power.

Curiously, no relationship was found with omega-3 fat intake as calculated from the diet surveys, suggesting that eating fish weekly may prevent brain ageing regardless of omega-3 content. But it may also be that eating fish is a marker for some other effect. People who ate fish were more likely to have a university education than those who didn’t. So perhaps it is mental exercise that was responsible for the changes in brain volume. There is also evidence that eating fish reduces the risk of heart disease. Maybe eating fish makes people smarter and more capable of understanding why they should be following the guidelines designed to reduce the risk of heart disease.

Joe Schwarcz

Green tea extracts and liver disease

green tea extractI think we are safe in saying that green tea doesn’t make taste buds frolic. So why do people drink it? The same reason for which the Chinese have been consuming it for millennia. Its supposed health benefits. Green tea doesn’t contain the flavourful compounds that form when tea leaves are allowed to ferment. During fermentation enzymes are released that convert the naturally occurring polyphenols in the leaves to a host of tasty compounds. Instead of being fermented, green tea is made by steaming or drying fresh tea leaves in order to prevent oxidation of the polyphenols. It is these polyphenols that in laboratory and animal studies show anti-cancer effects as well as increased rates of metabolism.

But how can on benefit from tea’s polyphenols without having to put up with green tea’s unappealing flavor? Supplement manufacturers have found a way. Just extract the catechins, the main class of polyphenols in tea, and plunk them in a pill. Then promote the pill as a cancer-fighting or fat burning supplement. But here we run into a problem. Such dietary supplements are poorly regulated and the amount of catechins they contain can be far greater than that available from drinking tea. The high doses may indeed help to increase metabolism and result in weight loss but possibly at a high cost. Just ask the teenager who walked into the emergency room at Texas Children’s Hospital with his chest, face and eyes bright yellow due to severe liver damage after using a concentrated green tea extract he bought at a nutrition store as a “fat burning” supplement. Doctors feared he may need a liver transplant but luckily his liver, an organ that has regenerative properties, managed to recover. He did, however, have to give up sporting activities and will require regular checkups of his liver function.

Unfortunately this is not an isolated case and such cases are not limited to green tea extracts. Various herbal supplements have been linked with liver damage, some because of undeclared ingredients, such as steroids. These are promoted as bodybuilding supplements and may actually have an effect because of the hidden steroids. People generally assume that herbal products that are sold are tested for safety and efficacy but this is not the case. Until regulations are tightened the incidence of liver damage from dietary supplements is going to continue to increase.

 Joe Schwarcz

Fenugreek and Sotalone

fenugreek and sotaloneIf you have eaten curry, you have probably tasted fenugreek. The seeds of this plant as well as its fresh leaves are commonly used as ingredients in curries. They are added for taste but they also impart a smell that is due to sotalone, a compound that at low concentrations has a distinct maple syrup-like odour. Since sotalone passes through the body unchanged, it can impart a scent both to the urine and sweat. The compound is actually used as one of the flavor components in artificial maple syrup and can be isolated from fenugreek seeds. Facilities that process the seeds often smell strongly of maple syrup and the scent can be carried quite some ways by the wind. Back in 2005 Manhattanites began to complain of a strong maple syrup odour and rumours circulated about it being some sort of chemical warfare. It took a while but eventually the smell was traced to a company in New Jersey that was processing fenugreek seeds. That rumor even made it on to an episode of 30 Rock, the popular sit com.

It is not only curry eaters who can smell of maple syrup. It can be an issue for lactating mothers who take fenugreek supplements to increase milk production. While there is much anecdotal evidence that this works, the few studies that have been carried out have shown mixed results. There is always a question of just how much to take, which is tough to answer because herbal supplements are difficult to standardize and often there is a mismatch between what is indicated on the label and what is actually in the product.

Herbal remedies are drugs and like any drug can have side effects. As a food fenugreek rarely causes problems but as a supplement it can result in loose stools and intestinal discomfort. Allergy to fenugreek is possible especially in people who have allergies to peanuts and chickpeas which are in the same botanical family. Since fenugreek can lower blood glucose, it can in some cases cause hypoglycemia. This is of special concern in diabetics because fenugreek may enhance the effect of antidiabetic drugs. On the other hand, because it can lower blood glucose, fenugreek may be of some benefit to diabetics, but again there is the problem of knowing how much to take because of lack of standardization.

Since fenugreek can cause uterine contractions, it should not be taken during pregnancy.When taken for lactation, the advice that is often offered is to slowly increase the dosage until the sweat or urine begins to smell like maple syrup. Breast fed babies may also smell of maple syrup if the mom has been ingesting fenugreek and that can lead to false diagnosis of “maple syrup urine disease.” This is a serious genetic disorder characterized by a deficiency in enzymes that metabolize the common amino acids valine, leucine and isoleucine. A buildup of these amino acids and their breakdown products can lead to severe neurological damage and eventually death. One of these breakdown products is sotalone, the odour of which was usually a clue to the diagnosis of maple syrup odour disease. Today, should the condition be suspected based on a baby’s failure to thrive, testing of the blood amino acids can detect the condition even before any scent appears. Serious consequences can then be avoided by adhering to a diet that is based on a special formula free of the problematic amino acids.

Some women take “Blessed Thistle” along with fenugreek because this herb also has a reputation as a lactating agent. In this case there is insufficient evidence for efficacy or about the safety of taking this herb during pregnancy or while breast feeding. Blessed thistle is not the same as “milk thistle” which in spite of its name has nothing to do with encouraging milk production. The plant derives its name from the characteristic white streaks on its leaves. An extract of milk thistle, often called “silymarin” is composed of several compounds that have a protective effect on the liver. Some strudies have shown a benefit in cirrhosis as well as fatty liver disease. One study even claimed effective treatment of poisoning caused by Amanita phalloides, one of the most deadly mushrooms known. It contains compounds that attack the liver.

Joe Schwarcz

Gluten-free diets and the mythologies surrounding them

gluten freeThis week’s column is guaranteed to generate controversy. There will be all sorts of anecdotes from people who say they have lost weight, gained energy and just feel better after eliminating wheat. I wouldn’t be surprised to hear claims that Lou Gehrig’s ALS was caused by eating Wheaties. And I’m sure I will be urged to just try a wheat-free diet instead of looking at the scientific literature.

Gluten-free diets and the mythologies surrounding them

You will never see Novak Djokovic’s picture on a box of Wheaties. Djokovic is a super tennis player and is easily in the same league as the athletes who have adorned the Wheaties box since 1934 when Lou Gehrig first urged us to try the Breakfast of Champions: “There’s nothing better than a big bowl of Wheaties with plenty of milk or cream and sugar.” Djokovic would disagree. No Wheaties for this champion. Diagnosed as “gluten intolerant” by his nutritionist, Djokovic has given up all foods that contain gluten, the mixture of proteins found mostly in wheat, barley and rye.

He claims that he feels “fresher, sharper and more energetic.” So how exactly was Djokovic diagnosed, given that there is no known test for gluten intolerance, aside from the variety known as celiac disease, which Djokovic does not have?

Djokovic’s “nutritionist” asked him to stretch out his right arm while placing his left hand on his stomach. He then pushed down on the tennis champion’s right arm and told him to resist the pressure, which he was able to do. Next, Djokovic was asked to hold a slice of bread against his stomach with his left hand while the nutritionist again tried to push down on his outstretched right arm. This time, he was able to push it down easily. The demonstration, Djokovic was told, showed that he was sensitive to gluten, which is why he had suffered so many mid-match collapses in his career.

Such a test, often referred to as “applied kinesiology,” is often used by “alternative” practitioners to diagnose allergies and nutritional deficiencies, as well as to promote the sale of “energizing” bracelets.

It has zero scientific validity, but that doesn’t mean that Djokovic doesn’t suffer from non-celiac gluten sensitivity. The correlation with the test may be accidental, but the condition may be real. Djokovic is convinced that avoiding gluten is a factor in his improved play and is not bashful about recommending that everyone give “gluten-free” a shot. And he is not alone. Others who sing the praises of a gluten-free lifestyle include such icons of science such as Gwyneth Paltrow, Miley Cyrus, Lady Gaga, Russell Crowe and Bill Clinton.

And then there is Dr. William Davis whose book Wheat Belly paints a picture of modern wheat as a satanic grain responsible for diabetes, high cholesterol, osteoporosis, cataracts, wrinkles, rashes, neuropathies, vitiligo, hair loss and schizophrenia — along with “man breasts,” “bagel butt” and of course, “wheat belly.”

If you are scientifically minded, it is worthwhile to read this book, just to see how masterfully Davis blends cherry-picked data, inflammatory hyperbole, misused science, irrelevant references and opinion masquerading as fact into a recipe for a cure-all.

Some of the “science” is just absurd. He talks about how wheat DNA has been mutated by exposure to sodium azide, and then points out that “the poison control people will tell you that if someone accidentally ingests sodium azide, you shouldn’t try to resuscitate the person because you could die, too, giving CPR.” The fact that sodium azide is a toxic chemical has nothing to do with its use in inducing mutations in genes. There is no azide in the product and inducing mutations to achieve beneficial traits is a standard technique used by agronomists.

Davis’s argument for wheat-causing osteoporosis is equally bizarre. He describes how wheat can give rise to sulphuric acid when it is metabolized. This is indeed correct. One of the amino acids in wheat protein, cysteine, does end up releasing some sulphuric acid in the body. And the body does use phosphates from bone to neutralize excess acid. The amount of acid released into the bloodstream from wheat is trivial; yet Davis calls it an “overwhelmingly potent acid” that rapidly overcomes the neutralizing effects of alkaline bases.” Poppycock. (Appropriately, that term originates from the Dutch term for “soft dung”.)

That, though, isn’t the worst of it. Davis panics readers with totally irrelevant statements about sulphuric acid causing burns if spilled on the skin. Get it in your eyes and you will go blind. True, but what does that have to do with traces formed in the blood from cysteine? Sulphuric acid in acid rain erodes monuments, kills trees and plants, Davis informs us. Yes it does. But linking this to eating wheat is an example of mental erosion. Davis also claims that proteins in wheat break down to peptides that have opiate-like activity and lead to wheat addiction. If that were true, we had better avoid spinach, soybeans, meat, dairy and rice, because these also contain the same protein fragments.

Davis also claims substantial weight loss by avoiding wheat. “If three people lost eight pounds, big deal,” he says. “But we’re seeing hundreds of thousands of people losing 30, 80, 150 pounds.” Really? Where is this documented? It isn’t surprising, though, that some people do lose weight on the “Wheat Belly” diet, given that cutting out wheat products results in a reduced caloric intake.

While wheat is not the great devil responsible for the plethora of ailments claimed by Davis, it is not completely innocent either.

“Non-celiac gluten sensitivity,” in which various symptoms resolve when gluten is eliminated from the diet, in spite of negative blood tests and negative biopsies for celiac disease, may affect as much as five to 10 per cent of the population.

Most of the evidence, though, is anecdotal; and similar improvements in health are described by people who avoid artificial sweeteners, shun MSG, eat only raw foods, engage in auto-urine therapy or walk barefoot to soak up the earth’s energy.

There is also accumulating evidence that improvements in health by avoiding gluten have nothing to do with gluten but rather with “fermentable oligosaccharides, disaccharides, monosaccharides and polyols” dubbed FODMAPs. These wheat components are poorly absorbed, and travel through to the colon where they provide a scrumptious meal for the bacteria that live there.

The problem is that these bacteria produce copious amounts of gas that distend the gut and cause pain as they dine on the FODMAPs. Unfortunately, other foods, including many fruits and vegetables, also contain these troublesome sugars, so a low-FODMAP diet is difficult to follow.

In the meantime, Novak Djokovic is winning titles and is winning other athletes over with his gluten-free diet.

Wouldn’t it be interesting to see how he would perform if somebody managed to sneak some gluten into his food?

I also wonder how Lou Gehrig would have done had he traded in his Wheaties for Rice Chex or Cornflakes.

I suspect just as well.

Joe Schwarcz

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