bite my words

Dispelling nutrition myths, ranting, and occasionally, raving


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Throwing the fish out with the oil

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For the most part I love Fooducate; however, I was a little surprised by this recent blog post on their site. The post referenced a recently published study that suggested our touting fish oil supplements (or even the recommendation to consume fatty fish twice a week) is faulty. They did not offer any thoughts or critique on the new “study”.

The study was actually an analysis of previously published research. They claimed that our recommendation to consume fish (or fish oil) was based solely on a research study of Icelandic Eskimos conducted in the 1970s. They assert that the findings of this study were misinterpreted and that the researchers did not even look at the prevalence of cardiovascular disease in the population they studied. They then looked at the other research on diet and CVD in Eskimo and Inuit populations. They only found one study that performed direct measurements on the Greenland Eskimo
population for assessing the presence of CAD or CAD risk factors”
. They state that this study, conducted before the Eskimo population had adopted a Western diet, found no difference between incidence of CAD in the Inuit population in comparison to American and European populations. Interestingly, I took a look at the original research study and the researchers actually found a lower risk of CVD in the Inuit population as compared to the Western population. Essentially the opposite of what the current researchers are claiming.

So… “What the heck does this all mean??” you may be wondering. Should you be eating fish twice a week? Should you be taking fish oil supplements? Well, unless you are a Greenlandic Inuit then this research may not apply to you at all. We can’t say that what’s healthy for the Inuit population is healthy for other populations. We also can’t be certain that it’s the consumption of fatty fish that reduced their risk of heart disease. It may be any of  number of other lifestyle factors that placed them at lower risk for CVD. Recent research into the benefits of fish oil has yielded mixed results. Some studies show benefits of fish oil consumption, others show negative effects of its consumption. As always, the best advice is that variety is the spice of life and it’s best to obtain your nutrients from whole foods. Yes, eat fish (limit the larger saltwater fish you consume though as it can be high in mercury), choose a variety. If you don’t eat fish, you might want to consider consuming a fish oil supplement. There may be benefits other than lower CVD risk associated with consuming omega-3s from fish/fish oil (such as mental and cognitive well-being, bone and joint health). Research is ongoing and you might want to wait before you turf your fish oil supplement or grilled salmon.


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Dr Oz gets schooled and says: #sorrynotsorry

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I’m sure that the whole Dr-Oz-goes-to-the-senate-and-gets-scolded thing is going to be all over all of the blogs for at least the next few days. Despite this, I still feel the need to throw my voice into the fray. I’ve ranted about Dr Oz and his ridiculous supplement (and dietary) proclamations many a time (too many for me to be bothered to even give you a link right now, feel free to search my blog for my scorn). It’s not just weight loss that’s a problem. It’s pretty much every dietary and supplement recommendation that he’s made. Eat a papaya every day? Come on, are we made of money (perhaps Dr Oz should read yesterdays post)? And what happened to variety is the spice of life. Any dietitian worthy of the “RD” after their name will tell you that variety is a key component of a healthy diet.

But that’s all history now, right? Dr Oz, the great and powerful Oz, has (gasp!) apologised for his role in the popularization of useless weight loss supplements. Does this really sound like the words of someone who is truly sorry: “For years I felt that because I did not sell any products that I could be enthusiastic in my coverage and I believe the research surrounding the products I cover has value.”? What I see here is Oz saying that by not putting his name on any product labels that he thought it was okay to tout each and every one of them as the next great MIRACLE weight loss cure on his show. Even more importantly, I see that Oz still believes in the “research” conducted on the products he promotes. Never mind that most of them have little to no scientific research to support their use as weight loss supplements. Never mind that those that do have research invariably have weak biased research. Never mind that he conducted his own “research” into the efficacy of green coffee bean extract using audience members.

Do I think that we’ll see any meaningful change as a result of this hearing? I doubt it. Dr Oz doesn’t believe that he’s done anything sincerely wrong and what he does is popular. Horrifyingly popular. Just a taste of some of the comments on his facebook “apology”:

Dr.Oz, you are amazing. You get people excited about living healthier and happier lives! You show is interesting, lively and is very enjoyable as well as more importantly very informative to watch. Thank you!!!

You have done far more good in your career than any other public medical professional, helping people take responsibility for their health and promoting preventive care and wellness. Don’t listen to the politicians, who are the MOST self-serving of our population and sell out every day to lobbying money. You owe no apologies.

You are a good doctor, and you have done nothing wrong. I am glad you stood up for what is right. Keep on doing what you do best Dr. Oz…
They go on and on in that vein. People want miracle cures. They don’t want to hear that losing weight (and keeping it off) is hard work. That’s why Dr Oz has 4.6 million likes on FB and a syndicated television show and dietitians (like yours truly) are tapping away writing unpaid blogs about nutrition in their spare time. As long as Dr Oz is being given a platform, as long as the network is getting the ratings, and as long as the public are swallowing every pill he proffers he is going to keep dishing them out.

 


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Why the home test for vitamin quality is crap

 

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I’ve had a number of people mention to me about testing vitamin quality by attempting to dissolve them. While this seems like a good idea, initially, upon further consideration, I can think of a number of flaws with attempting this at home.

The Consumer Lab provides a step-by-step guide to testing the disintegration of vitamins at home. They recommend putting the pill in water warmed to body temperature and then stirring continuously for 30 minutes, maintaining the water temperature. Unless the pill is chewable, enteric coated, or timed-released, it should break down. The implication is, if it doesn’t, it’s not breaking down when you ingest it and your body isn’t getting the nutrients from it. But, there are some problems with this premise.

First, your stomach is a highly acidic environment. Stomach acid usually has a pH of 1.5-3.5. Water, on the other hand, has a pH of about 7 (i.e. neutral). If you wanted to mimic the conditions of the stomach, you would need to use warmed lemon juice, or a similar acid.

Second, creating a warm, acidic environment isn’t enough. Most vitamins are recommended to be consumed with food. During digestion, the stomach releases a whole host of digestive enzymes which work to break down your food, and some of them would likely also have an impact on breaking down any vitamin and mineral supplements. Together the stomach secretions and jumbled-up food forms “chyme” which is generally ready to leave the stomach after 1 to 4 hours. That time-frame gives your vitamin a whole lot longer to break-down than the 30 minute warm water home test does. The stomach also secretes “intrinsic factor” which essential for the absorption of vitamin B-12 (don’t forget to add that to your cup of body temperature lemon juice).

Third, digestion doesn’t end in the stomach. After the chyme moves from the stomach to the small intestine which is actually where most digestion takes place over 3 to 10 hours.

Fourth, as the Consumer Lab test notes, a number of vitamins are designed to take long periods to break-down (i.e. timed-released). Others (i.e. enteric coated) are designed not to break-down until after exiting the acidic environment of the stomach and entering the neutral environment of the small intestine.

Fifth, have you ever shat out an intact vitamin pill? Unless your body’s stashing whole pills somewhere along your digestive tract, it’s probably safe to say that it’s being broken-down along the way.

Sixth, just because a supplement is breaking-down in your body doesn’t necessarily mean that it’s being absorbed. Determining that it dissolves in a cup of warm water won’t tell you if you’re obtaining any nutrients from it.


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The vitamin D debate: Won’t someone please think of the children?!

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The latest “study” on vitamin D reached the conclusion that vitamin D does nothing to prevent myriad medical conditions. You may be wondering why I placed study in quotation marks. That’s because it’s not actually a new study. It’s an analysis of the results from a number of randomized controlled trials of vitamin D supplements.

Of course, there are the usual issues with meta-analyses. We don’t know for certain if the authors cherry-picked the studies they chose to look at. We don’t know (without spending substantial amounts of our own time, and probably money) if the original studies were flawed. It’s a good thing that it’s good that this analysis looked at studies using a randomized control model. This avoids the obvious potential confounding factors seen with observational studies. However, I have some doubts that these studies would have been conducted over long enough time-spans to accurately assess the use of vitamin D supplements. After all, they were looking at the effects of vitamin D supplementation on myocardial infarction or ischaemic heart disease, stroke or cerebrovascular disease, cancer, total fracture, hip fracture, and mortality. To truly determine the effects of vitamin D supplementation on these conditions supplementation would have had to begin in childhood and continue until death (or at least very old age).

The authors found that vitamin D did not affect outcomes by more than 15% for any of the above conditions, aside from hip fractures in institutionalized seniors.

I’m inclined to think that we may be expecting far too much from vitamins and minerals. Just because vitamin D probably doesn’t prevent cancer or heart disease doesn’t mean that there aren’t any benefits to be obtained from taking it as a supplement. Perhaps it may prove to be beneficial in mood regulation, cold prevention, or something else less earth shattering than these studies looked at.

Perhaps there is no benefit to taking vitamin D supplements. However, I’m not quite ready to toss my bottle. I know that I can’t meet the currently recommended amount of vitamin D through diet alone. And I’m certainly not getting any from sun exposure this time of year. I don’t think that we should dispose of the current vitamin D recommendations on the basis of one meta-analysis. I’m certainly open to changing my mind but for now I’d like to hedge my bets. I’d rather risk taking a “useless” vitamin D supplement than risk experiencing adverse health consequences from not consuming sufficient vitamin D.

In addition, I worry that research such as this may lead to new parents neglecting to supplement their infants with vitamin D and causing a resurgence in rickets. Just because there’s uncertainty about the long-term outcomes of vitamin D supplementation doesn’t mean that we don’t know the benefits in early childhood.


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Vitamin supplements: deadly or life saving?

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Last week everyone was getting worked up because an editorial in the Annals of Internal Medicine advised against taking vitamin supplements. I wish that I could unequivocally state that they were correct (or incorrect) in this assessment. Unfortunately, this is a complicated issue and I don’t think that we have all of the answers yet.

We know that there are problems with the supplement industry. It’s not well-regulated. Some herbal supplements were recently found to contain ingredients other than those stated on the label, some even contained none of the sole ingredient they claimed to contain. It’s not a stretch to presume that this issue extends to supplements beyond the herbal variety. Last year researchers found that vitamin D supplement often contained hugely variable quantities of vitamin D, even within the same bottle.

An issue unique to multivitamins is that some minerals impede absorption of other minerals when consumed together (for example, zinc and copper). Other vitamins and minerals actually work better together (think calcium, magnesium, and vitamin D). When we’re taking a multivitamin we’re almost certainly not absorbing many of the vitamins and minerals listed on the label (assuming the label is correct in the first place). Does this mean that we should give up on supplements altogether? Possibly not.

The editorial refers to three specific studies. The important thing to note if that these studies looked at people who were not nutrient deficient. The problem with this is that many of us are nutrient deficient. Canadians have difficulty meeting their nutrient needs for calcium, magnesium, and vitamin D through food alone. We also tend to fall short in consumption of potassium as well as EPA and DHA (essential omega-3 fatty acids). There is also the fact that individual nutrient needs vary and that increased nutrients are needed during specific life stages. For example, folic acid is needed early in pregnancy to prevent neural tube defects in infants (1) and many nutrient needs are increased during pregnancy and lactation. Smokers have increased vitamin C needs and athletes have increased needs for nearly everything. Infants require vitamin D supplementation to avoid rickets. Vegans and seniors need vitamin B12 supplements. Etc.

Another problem with the basis on which the authors of the anti-supplement editorial made their recommendation is that they were looking at extremes. They asked: Do multivitamins prevent cancer? Cognitive decline? Heart attacks? Just because vitamin supplements don’t seem to prevent these conditions doesn’t mean that there aren’t other potential benefits to supplementation. More “minor” aliments may be ameliorated by consumption of supplements. We also may have been simply too late to see benefit from supplementation in those involved in those studies. As with osteoporosis which is a pediatric disease with geriatric consequences, these diseases are likely a result of exposures and lifestyles starting in utero.

So, should we take vitamin and mineral supplements or not? I think that it’s a bit of a gamble either way. On one hand you may not be getting what you bargained for in a supplement. On the other hand, you might be risking nutrient deficiency by avoiding all supplements.

Obviously it’s best to try to meet your nutrient needs through food. Realistically, most of us do not do this. If you’re able to determine what specific nutrients you’re lacking in your diet then it’s best to supplement with only those nutrients. Try to select supplements that have an NHP number on them to ensure a minimal level of regulation. And, of course, too much of anything can be a bad thing. Unless advised by your MD or nurse practitioner to take a high dose (and even then, you might want to question them) of any supplement avoid reaching or surpassing the upper limit.