bite my words

Dispelling nutrition myths, ranting, and occasionally, raving


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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.


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I don’t think you’re ready for this gelatin

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Apparently gelatin is the latest “superfood”. Yep, the stuff in jello. Of course, you have to take away the added sugar, colour, and flavour for it to ascend to “superfood” status. You all know how I feel about “superfoods”. They’re a super scam. Sure, many of them are nutritious (think avocados and blueberries) but there’s nothing about them that makes them superior to other fruits and vegetables.

Okay, even if gelatin isn’t a “superfood” is it exceptionally good for you? Should we all be eating plain jello or taking gelatin capsules? Let’s take a look at the specific claims in the article…

Improved digestion - According to pretty much every wellness blog and self-proclaimed nutritionist gelatin improves digestion. However, as far as I can tell there is no scientific basis for this claim. I can’t find any research on the topic. This isn’t to say that gelatin doesn’t help digestion, but we don’t currently have any reason to believe that it does. 

Reduced food intolerance and allergy - This is a frightening claim. It would be lovely if it were true; people with peanut allergies could eat some gelatin and then chow down on some peanuts. And what about those people who suffer from gelatin allergy?

Strong bones and flexible joints - Because gelatin is made from animal cartilage (unless it’s the vegetarian variety which is made from seaweed) it’s easy to see how people draw the connection between gelatin and joint and bone health. However, despite this widespread belief, there’s no evidence to support the use of gelatin for bone and joint health. The same applies for Thick hair, strong nails and healthy teeth. Just because a substance (e.g. collagen) acts to strengthen our hair doesn’t mean that it will do so if we consume it orally. Otherwise, we would be able to improve our eye sight by eating eyeballs. A bit of an exaggeration, but you get the point.

Ageless skin - See the last point above. I’d also like to add that skin ages! Sorry, no matter what supplements we take, and what lotions and potions we apply we are all going to get wrinkles. Want to retain your youthful complexion for as long as possible? Eat a healthy diet with a variety of fruits and vegetables and fluids, get enough sleep, exercise, avoid tanning and sunburns.

Improved sleep - I was able to find one study that suggested that 2 grams of glycine ingested at bedtime improved subjective sleep quality. There’s 1.3 g of glycine in one serving of gelatin so it’s possible that you might obtain some benefit from it. However, this quantity may not be present in capsules so before you go running out to buy them before bed you might want to make sure that you’re getting what you’re paying for.


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Grocery Store Lessons: Protein powder

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As with all foods/supplements, all protein powders are not created equal. Protein powder isn’t something that I consume much of. I find it’s often gritty and overly sweet and I’m confident that I can get adequate protein from consuming whole foods. However, for the sake of product knowledge, I do occasionally try a protein shake as part of my breakfast.

I always look at the protein content of each protein powder. As an aside, most tend to be about 24 grams per serving, although, some, such as hemp protein powder, can be considerably lower (8-15 g). Something I never considered looking at was the sodium content until one day I just happened to notice it on the package shown on the above left. I was shocked that a serving of protein powder would contain half a day’s worth of sodium. It is a “sport” protein so maybe that’s why; to replace electrolytes lost during an exceptionally sweaty workout. Still, I’m sure that most people wouldn’t expect to be getting so much sodium from a protein shake and I imagine that there are others out there like me who never even thought about looking at this information. I started looking at the nutrition information labels on other protein powders in the store. Most were similar to the much more reasonable 130 grams seen in the whey protein powder (pictured above right).

If you do consume protein powder regularly you might want to check the label to ensure that you’re not getting more sodium than you bargained for.

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