bite my words

Dispelling nutrition myths, ranting, and occasionally, raving


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Insane in the Grain Brain

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My library hold finally came in! No way was I paying to read Grain Brain. I like to financially support quacks as little as possible.

First thought: Including a quote from Dr. Oz on the front cover of your book does little for your credibility.

Second thought: I really like the font used for the Contents page.

Introduction“I’m also a founding member and fellow of the American Board of Integrative and Holistic Medicine.” Cue alarm bells! He said the “H-word”! I promptly googled the organization to learn more. Hmm… While I like the general notion of treating the patient as a whole I’m not sure about this principle: “Integrative holistic physicians strive to relate to patients with grace, kindness and acceptance, emanating from the attitude of unconditional love as life’s most powerful healer.” Love as the most powerful healer?? Call me crazy but I’m not going to my doc for love to heal me when I have an injury or infection. For more about the ABIH check out this post on Science-Based Medicine. Which confirms my fear that this certification has essentially zero meaning. Okay… So the author, David Perlmutter, is the founder of a quack organization. Still, just for fun, I’ll keep reading and see what his “proof” regarding the toxicity of grains is.

Modern wheat is not the same as the wheat of our ancestors. Yeah, yeah. We’ve heard this all before.

“Why is precious little information made available about how we can keep our brains healthy and stave off brain diseases?” I do like this question. Also, I suspect the answer is the same for the brain as for other organs: get plenty of exercise, avoid being sedentary, cook for yourself, and eat more veg. Oh, wait. Not according to Perlmutter, “it’s pointless to consume antioxidants.” Forget the veg, apparently we should all be eating more fat and cholesterol.

Self-Assessment: Ooh! This should be fun! I got 7 out of 20. Zero is optimal but at least I’m not in the “hazard zone” which is anything over 10.

Chapter 1“As many as 40 percent of us can’t properly process gluten”. Reference please. Where did this figure come from and what precisely does inability to properly process gluten mean?

Yes, cholesterol is essential in our bodies. However, a dietary source of cholesterol is not essential. Our bodies can make it. Also, what does this have to do with grains being the cause of brain degeneration and diseases?

Chapter 2: I wonder what this “test for gluten sensitivity” he’s ordering for his patients is. I can’t dispute these tales of improvement in patients following elimination of gluten. However, it’s important to note that we don’t have all of the details and elimination of gluten may not have been the “cure” for migraines and bipolar disorder Perlmutter wants us to believe it is.

A lovely image of a brain scan of a “gluten sensitive” patient versus one of a “normal” patient shows extensive damage in the GS brain. Obviously, this is proof that gluten causes brain damage. Or is it? Remember, correlation does not equal causation. And one brain scan image does not mean gluten will destroy your brain.

In the chapter about gluten Perlmutter says, “one of the main reasons why consuming so many grains and carbs can be so harmful is that they raise blood sugar”. Huh? So the cause of brain disorders is gluten, which is a protein, which would not impact blood sugar. So why are we now talking about carbs?

Chapter 3: “I’ll explain why consuming excess carbohydrates – even those that don’t contain gluten – can be just as harmful as eating a gluten-laden diet.” Sigh. Carbs are evil, fat is good. This is just Wheat Belly redux. Also, while I’m in agreement that all fats (with the exception of man-made trans-fats) can be part of a healthy diet and some of us need more (or less) than others, I think we also need to remember that fats contain more calories per gram than other macronutrients. Thus, if weight control is a concern, we must be careful not to consume overly large portions of calorie-dense high-fat foods.

Perlmutter argues that elevated cholesterol is not only not a risk factor for cardiovascular disease, it’s actually protective against CVD, ALS, and other diseases. The primary basis for this claim was a large study in Norway. The researchers found that there was a U-shaped association between total cholesterol and mortality from CVD. This would suggest that cholesterol has an optimal level (between 5.0 and 7.0 mmol L -1). People below 5.0, or at 7.0 or above, were more likely to die from CVD during the course of the study. Interesting indeed. However, those who had CVD at the start of the study were excluded and the researchers didn’t look at the difference between HDL and LDL profiles. I can’t help but wonder if examining these things would have made any difference to the findings. Even assuming their findings are accurate, they still don’t suggest that high levels of serum cholesterol are protective. They merely suggest that both high and low cholesterol may be associated with CVD.

Perlmutter moves on to argue that the use of statins increases the risk of developing Type 2 Diabetes (remind me again how this pertains to grains and gluten being toxic?). He cites a 2012 study that found a 48% increased risk of developing diabetes for women who took statin medications in contrast to women who did not. That sounds huge but it’s actually not as big as it sounds; 9.93% of statin users were diagnosed with DM2 versus 6.41% of non-statin users. This was also an observational study so causal claims cannot be made. While researchers did control for some confounders it’s entirely possible that there was another reason for the relatively greater risk experienced by the statin users, like, oh, say elevated LDL or another related health condition. There was also a large difference in the sample sizes for each group (10, 834 statin users and 143, 006 non-statin users) which makes me leery about drawing precise comparisons.

Chapter 4: Near the end of this chapter Perlmutter cites a 2012 study of weight loss maintenance (he fails to make the maintenance part very clear) as proof positive that a low-carb, high-fat diet is “the best diet for maintaining weight loss.” To be clear, the study had participants lose weight and then put them on one of three possible weight-loss maintenance diets for 4 weeks. They did find that the low-carb diet “produced the greatest improvements in most metabolic syndrome components examined herein” with a couple of caveats: 1. participants also experienced elevated urinary cortisol excretion 2. C-reative protein was found to be higher in this group. So, while some areas, such as resting metabolic rate, were better for participants on this diet, there were also negative effects. In addition, it’s important to note that the sample size was very small, only 21 people. Also, four weeks is not the same as a lifetime. It’s impossible to extrapolate from this experiment that a low-carb, high-fat diet is the optimal diet for health. Nor can we tell if it’s a realistic diet. Even if it does prove to be optimal for health it doesn’t really matter if nearly no one finds it possible to adhere to. I think that Perlmutter is taking it a little too far (yes, I’m being kind) to draw the conclusion that we should all switch from carbs to fats on the basis of this study.

Chapter 5: Perlmutter is making the argument for neurogenesis and discussing the benefits of exercise (I fully support this) as well as caloric restriction (I think the jury’s still out on this one). I do find it interesting that he’s advocating for a high-fat, low-calorie diet. I would think that this would be very difficult to follow; eating small amounts (Perlmutter recommends reducing caloric intake by 30%) of calorie-dense foods likely wouldn’t be very satiating. Just me speculating though.

I can’t help but think that Perlmutter is cherry picking research that supports his hypothesis. Grain Brain reminds me of how I used to write research papers in high school. I would develop an outline, start writing, and find sources that supported my hypothesis to use as citations.

Chapter 6: In this chapter, Perlmutter discusses the possible connection between gluten sensitivity and various mental illnesses; including: depression, autism, tourette’s, and ADHD. Complete with compelling tales of curing patients by placing them on gluten-free diets. While there may be some connection to gluten sensitivity in some of these illnesses (a recent study found a correlation between autism spectrum disorders and positive serologic celiac disease – but not for gut mucosa – test results) I think that without the corresponding evidence that Perlmutter is providing many individuals with false hope. Anecdotal evidence is not the same as scientific evidence and it’s important to note that, in most cases, no link (correlational or causal) has been drawn between gluten and mental illness. That’s not to say that gluten-elimination isn’t worth trying but in the majority of cases it’s unlikely to alleviate symptoms.

I’m reading about how a study of children with celiac disease found an increased risk of headaches of 833% in comparison to the general population. I decided to take a look at the original research Perlmutter cited with the hope of going on a little rant about relative risk (after all, it was 5% of the children in the study with celiac disease who experienced “headache”, versus 0.6% in the general population, still a small minority of children). However, the article that I found that matches the citation by Perlmutter doesn’t contain any such information. In fact, it contains zero mention of celiac disease or gluten whatsoever. Perhaps the citation is mismatched? (Let’s give Perlmutter the benefit of the doubt here). Regardless, it makes it that much more difficult to dispute (or support) his claims when the claims and the citations don’t correspond.

Chapter 7: In this chapter Permutter states, ” many of today’s physicians… don’t have a firm grasp of nutrition and its effects upon your health.” Hear hear! Cue the opportunity to promote the services of registered dietitians. Oh, wait. Perlmutter simply says that he hopes this will change with the next generation of doctors. Sigh. He then goes on to list a number of supplements that apparently we should all be taking.

DHA – Yes, along with EPA in fish oil, this may provide some neurological and cardiovascular benefits (1). Resveratrol – The jury’s still out on this one but more recent research has put a damper on earlier studies praising it as a life-extender (2). Turmeric – This spice is still being researched, and while promising, no conclusions have been reached regarding its benefits. The study Perlmutter cites was epidemiological research which asked residents of Singapore how often they ate curry. Those who ate curry occasionally, often, or very often, performed better on a test of cognitive ability. Of course, there’s potential for missed confounding variables, as well as the possibility that the difference could be attributed to some other component of curry. Probiotics – Again, we are still in the early stages of research linking gut microbiota and brain health. Perlmutter advises against consuming some probiotic foods as they often come with too much sugar. Instead he suggests taking a supplement. As a dietitian, I always think that it’s best to obtain your nutrients from foods whenever possible. Add foods like plain yoghurt, kefir, sauerkraut, miso, and kimchi to your diet to obtain probiotics. Coconut oil – There is some interesting research underway investigating the effects of coconut oil on Alzheimer’s patients (3). I certainly think that it’s a good idea to incorporate a variety of fats in our diets. However, I don’t think that we should go overboard with any one food. Alpha-lipoic Acid – May have some neurological benefits but the research thus far is not strong (4). Vitamin D – It seems like for every positive study regarding vitamin D there’s another study claiming that it’s useless, or even harmful. In our Northern climate, until research shows otherwise, it is still prudent to supplement with Vitamin D during the winter months.

Chapter 8: Shocker: I wholeheartedly agree with everything Perlmutter has to say in this chapter. He is emphasizing the importance of exercise for brain health. Nothing about grains or carbs.

Chapter 9: Another chapter without mention of grains and carbs. Another chapter I actually agree with Perlmutter. Sleep is vitally important for health.

Chapter 10: We’re just getting into general healthy living tips now and recommendations for how to implement the Grain Brain diet. Most of them are perfectly reasonable. Following this, there are some recipes.

As I sat eating birthday cake (it’s birthday season in my family) and contemplating how to conclude this post I commented to my boyfriend, “Who knows, maybe eating cake will give me Alzheimer’s one day.” Considering how few people develop Alzheimer’s disease (14.9% of Canadians over 65 have some form of dementia) and how many people consume grains (statistics unavailable but I’m assuming it’s roughly 100%) based on the current lack of robust evidence it’s a risk I’m willing to take. I hope to celebrate my birthday tomorrow with some cake.


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What the WHO sugar recommendations look like

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It was all over the news last week: the World Health Organization has released draft guidelines on sugar intake. These guidelines recommend a further reduction in added sugar intake from less than 10% of total daily calories to less than 5% of total daily calories. They state that this would be roughly 6 teaspoons of sugar a day for the average person. But what does this really look like?

Let’s look at the “average” person first. The “average” sedentary Canadian woman (31-50 years of age) needs roughly 1, 800 calories per day (1). Honestly, that sounds like rather a lot to me. I’m shorter than the average Canadian woman but far more active; my job is very physical and I’m currently training for the Boston Marathon and that’s about all I need in a day. Anyway… Let’s pretend that Health Canada isn’t over estimating our caloric needs. That would mean that the average Canadian woman should aim to have no more than 90 calories a day from added sugars. Knowing that one gram of sugar contains about 4 calories that means that this Average Woman would be permitted 22.5 grams of added sugar a day, or 5.63 teaspoons.

The Average Man (same age range) needs about 2, 350 calories a day. That would mean that he could have 117.5 of those calories from added sugar, or 29.38 grams, or 7.34 teaspoons.

Now, just to be clear, even though your body doesn’t distinguish between added sugar, refined sugar, unrefined sugar, naturally occurring sugar, yada yada, the WHO is only referring to added sugars. Lest you think that the food industry can get tricky and use pureed fruit or fruit juice concentrate to sweeten foods and get around these counting as “added sugars” these have been included in the definition of added sugar.

Just as most of the sodium in our diets is hidden in processed and packaged foods, so is much of the sugar. It’s not going to be as simple as eliminating the teaspoon of sugar in your cup of tea. Although, if you’re one of those people who adds two sugars to your coffee, once you’ve had two cups you’re creeping up on that limit.

How easy is it to reach that limit? Here are a few common “foods” and their respective sugar contents:

A small (16oz) Coke contains 41.4 g of sugar or 10.35 teaspoons (2).

A medium DQ Blizzard contains 74 g of sugar or 18.5 teaspoons (3).

A vanilla latte at Starbucks has 35 g of sugar or 8.75 teaspoons (4).

A 3/4 cup serving of Liberte 2% Coconut Greek Yoghourt contains 19 g of sugar or 4.75 teaspoons (reference: the tub in my fridge).

Two slices of Dempster’s 12 Grain Bread contain 6 g of sugar or 1.5 teaspoons (5).

Check out this infographic for more.

To be fair, some of these sugars will be naturally occurring. But… How are we as consumers to know how much of the sugar is naturally occurring and how much is added? And does it really matter? Unless we are eating diets that consist solely of unprocessed foods it’s going to be damn near impossible for any of us to know precisely how much sugar in a food is added and how much is naturally occurring. Unless food labels start changing to indicated added and naturally occurring sugars it’s going to be a bit of a guessing game. Personally, I think it would be better if we focussed less on individual nutrients and focussed more on overall diet. Recommending limits on processed and fast food and encouraging increasing consumption of home cooked meals and minimally processed foods would be easier to follow. The way these recommendations are framed they just steer people in developed countries toward foods sweetened with non-nutritive sweeteners and allow the food industry to market nutritionally-void foods as healthy choices by replacing sugar with other things. They also make things like fruit juice perfectly acceptable even though they are essentially just liquid candy.

If you’re interested in contributing to the draft guidelines you can download the complete document here and send your comments in by March 31st.


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Sugar: Not such a sweet heart

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A study was published in JAMA Internal Medicine last week that got everyone all worked up! In case you somehow missed it, sugar is the latest white food to be blamed for obesity. While this study didn’t look at obesity it still added a whole whack (that’s a real unit of measurement, right?) of fuel to the fire of those railing against sugar.

The study looked at the data from NHANES a huge long-term US health and nutrition study and concluded that those who are consuming diets with more than 25% of calories from added sugars are significantly more likely to perish from heart disease than are those who are consuming less than 25% of their daily calories from added sugars.

Of course, there are the usual caveats with this sort of research. They relied on food frequency questionnaires which are notoriously inaccurate and put much of the research based on them in question. A little aside: I used to work as an interviewer for a large Canadian statistical agency and I wouldn’t trust any of the nutrition information we collected. I mean, vegetable intake was determined by asking questions such as “how often do you eat carrots?”. I think we asked about consumption of three kinds of vegetables (including potatoes which were meant to exclude fried and potato chips) and “other vegetables” to determine total vegetable intake. People could answer on a daily, weekly, or monthly basis. Interviewees often seemed confused about hot to answer the questions and I often wondered to myself what people were eating when, based on their answers, they seemed to eat one carrot a month and a slice of bread everyday. Anyway… let’s put aside the fact that these studies are flawed. Let’s pretend that we do actually know how many calories people are consuming every day from sugar. Can we be sure that the increase in heart disease is attributable to sugar consumption? Perhaps it’s due to displacement of other foods. If someone is consuming 25% of their daily calories from sugar that either means that they’re consuming an excessive number of calories and obtaining adequate quantities of required nutrients, they’re consuming excess calories but not meeting nutrient requirements, or they’re consuming reasonable amounts of calories and not meeting nutrient requirements. Odds are, if they’re getting too much sugar, they’re getting too little of a number of essential vitamins and minerals.

I don’t think that we should be obtaining 25% of our daily calories from added sugar. While the “safe” amount of sugar is still up for debate, the previously suggested maximum of 10% of daily calories from the WHO seems reasonable and achievable. I don’t think that we should be rushing out and lobbying the food industry for sugar to be removed from everything. I certainly don’t think that this research lends any support to the case for sugar causing obesity. I think that we should take it as a caution and aim to be more conscious of the sugars we’re consuming on a daily basis.


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Low-fat vs low-carb

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There’s a lot to unpack from this Daily Mail article a friend alerted me to. The premise: a couple of identical twin doctors decide they need to lose weight. In order to determine which fad diet is better, one goes low-carb, the other goes low-fat. The fact that they are genetically identical and maintained similar levels of physical activity means that they assumed any differences observed would be due to diet. While there is merit to using identical twins in research studies it’s important to note that this was not a scientific experiment. One subject in each group doesn’t lead to robust findings. Other issues: obviously both men knew which diet they were on and there was no control group. So, this wasn’t good science but it’s still possible that we could learn something interesting from their little “experiment”.

Before we look at what they “learned” from the experiment there are a few things in the article that I want to touch on. Firstly, the headline states that “one twin gave up sugar”. Well, yes, but this twin also restricted all forms of carbohydrate, not just sugar. The twin who went on the low-carb diet thought that it would be effective because of the insulin hypothesis of weight gain.

Because these carbohydrates are highly refined, they tend to raise blood sugars and blood insulin levels quickly.  This will tend to cause weight gain and obesity.  This is known as the Carbohydrate-Insulin Hypothesis (CIH), and is the basis of the Atkins diet and many other low carbohydrate (Dukan) and very-low-carbohydrate diets (ketogenic diet). (1)

While it sounds convincing, we know this hypothesis to be incorrect. For one thing, there are many people/populations who consume high-carbohydrate diets and never develop obesity. For another, insulin on its own does not cause obesity (2). Minor quibble, really, but as doctors discussing weight loss they should have their facts straight. Obesity is complicated and there’s no smoking gun out there.

An important point that they make is:

…despite being doctors – I also have a degree in public health – neither of us knew much about losing weight and eating healthily. 

These topics fall between the cracks at medical school. Yes, we understood biochemistry and food metabolism, and knew a lot about the consequences of being overweight. But which diets work, why we eat too much and why losing weight is so hard don’t sit within any medical speciality.

Pity that they didn’t take the opportunity at this stage to point out that this means that assuming your family doctor will tell you if your weight is a health concern or that they are a good resource for weight loss are dangerous assumptions. If you are concerned about your weight being a health issue you need to speak up and voice those concerns. Ask for a referral to a dietitian who specialises in weight management or to a reputable weight management clinic. I really wish they would have mentioned the great resource that we dietitians can be for all things diet and nutrition.

As you may have guessed, both doctors lost weight during the course of their experiment. I hope that they were the only ones who were surprised by this outcome. Naturally they lost weight; they were both on highly restrictive diets, they were both active males, and this was done over a very short period of time (one month). Imagine trying to sustain a diet with the barest minimum of fat or no carbohydrates for the rest of your life!

Fortunately, the doctors reached a conclusion that I actually agree with! That: “For any diet to work you have to be able to keep it up for the rest of your life.”  As I’ve said many times before: to see sustainable weight loss you need to make sustainable changes.


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Is sugar the “new tobacco”?

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The headline reads “Why are health experts calling sugar the new tobacco?” Because it’s catchy and makes for great headlines, duh!

I know that a lot of people are going to be pissed off with me for not taking up the cause and demonizing sugar. Sorry guys. I agree that most of us consume too much sugar (and too much of anything is a bad thing). I agree that excess sugar can cause cavities. I agree that the vast majority of us like sweet foods. However, I don’t believe that sugar is truly addictive… There is a difference between addiction and desire. Just because rats like oreos and sugar “lights up pleasure centres” in our brains doesn’t make it addictive.

I keep seeing claims that our bodies process calories from white sugar differently than calories from other foods. This makes no sense. The common definition of a calorie (technically a kilocalorie) is: the amount of heat required to raise the temperature of one kilogram of water one degree Celsius (1). There is no way for your body to differentiate between “types” of calories. There is only one type! Your body also can’t distinguish between sucrose in white sugar and sucrose in an apple. It is a chemical compound. It is what it is.

Calling on the food industry to reduce sugar content of foods is a dangerous proposition, in my opinion. Remember when we asked food manufacturers to reduce fat content? They added salt and sugar. Remember when we asked food manufacturers to reduce sodium? Not that much ever came of this. Point being, when they take something out they put something else in to replace it. We now know that fat is not inherently bad for us, nor is sodium, nor is sugar. No one of these things alone is causing obesity. Rather than asking food manufacturers to reduce the sugar content of their foods we should be calling for less heavily processed foods.

Sugar is not the new tobacco. It’s the new scapegoat in the obesity wars.

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