Dispelling nutrition myths, ranting, and occasionally, raving

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Strong bones

Last week a US government advisory group announced that there is no benefit for healthy “older” women to take low-dose calcium or vitamin D supplements. These conclusions were based on findings that these supplements do not appear to reduce the risk of broken bones.

There are a few important things to note about this pronouncement: 1. This message applies only to healthy older women. Women who are suffering from certain illnesses may require more of some nutrients and should consult with their doctor before stopping (or starting) any supplement regimen. 2. The advisory group did not look at higher supplement doses. There may be benefits (or risks) to consuming higher supplemental doses. 3. The announcement was based on risk of broken bones in comparison to risk of kidney stones. The advisory group did not look at any benefits of supplementation other than bone health. There may be additional benefits to vitamin D supplementation (again, or risks) we just don’t have sufficient research to advise on this basis yet.

I think that the most important lesson we can take away from this study is that many illnesses that befall us when we’re elderly are a result of exposures and lifestyle during our youth. As I remember learning in school: osteoporosis is a pediatric disease with geriatric consequences. We can’t mistreat or neglect our bodies when we’re young and then expect to make up for it when we’re elderly. To ensure strong healthy bones as seniors we need to ensure that children and young adults consume healthy balanced diets; including adequate vitamin D (which may require supplementation) and calcium. Children also need to engage in regular physical activity and we need to continue to exercise throughout our lives to maintain muscle mass and strong bones.

While it’s never too late to start leading a healthy life, it’s also never too early.


The many faces of calcium

A few people commented on a post last week regarding calcium. I thought that I’d write a little bit more about calcium to clear up a few questions.

The first is calcium in foods. While certain foods such as spinach are a good source of calcium (about 31 mg per raw cup) they may also contain other components (in the case of spinach, oxalic acid) which bind to the calcium and inhibit absorption. Foods that are high in oxalic acid include: sweet potatoes, rhubarb, and beans. Foods that are high in phytic acid include: high fibre foods and grains, beans, nuts, and seeds. Studies have not been able to determine the full extent to which these inhibitors actually affect absorption; however, if calcium is a nutrient that you may not be getting enough of it is worth considering consuming calcium-rich foods in meals separate from these foods. You may have also heard that coffee and tea can lower calcium absorption. They do increase calcium excretion due to the caffeine but the amount is insignificant (about 2-3 mg) so you can continue to drink your lattes to get your calcium if that’s your thing.

The amount of calcium consumed in a sitting can affect absorption. Absorption rates are highest at amounts of 500 mg or less. Thus, taking lower dose supplements spread throughout the day is likely to be of more benefit than taking one large dose a day. The type of calcium supplement you take makes a difference as well. Calcium carbonate (the most common supplemental form of calcium) is 40% calcium and should be taken with meals as stomach acid is necessary for proper absorption. Calcium citrate is more expensive than calcium carbonate, is 21% calcium, but need not be taken with meals for absorption. Other, less common forms of calcium supplements are: calcium phosphate (38% calcium), calcium lactate (13%), and calcium gluconate (9%).

Other factors can increase the absorption of calcium present in foods. For example, a cup of cooked spinach provides about 250 mg of calcium. Consumption of vitamin D also increases calcium absorption. Your age and need for calcium also impacts absorption rates. Calcium absorption is highest in young children and in women during pregnancy as it’s needed for building bone mass. Absorption continues to decrease throughout adulthood; hence higher recommended consumption amounts for women over age 50 and all adults over 70.

As mentioned previously, milk, and fortified milk alternatives, are all good sources of calcium. In addition, here are a few more sources to consider: plain yoghurt (450 mg/cup), Parmesan cheese (390 mg/oz), canned salmon, with bones (210 mg/3 oz), tofu, made with calcium carbonate (140 mg/0.5 cup), kale, cooked (99 mg/cup), dry roasted almonds (85 mg/25 nuts).


Got fortified cow beverage?

I’m getting caught-up on my nutrition article reading. You may have seen headlines all over the news a few weeks ago about how many children are drinking too much milk.

I think that many parents have been convinced, dare I say by the dairy industry (under the guise of Canada’s Food Guide), that children need lots and lots of milk to have strong teeth and bones. Unfortunately for all of us milk loathers who suffered through the dreaded milk program in grade school, this is not true. Yes, milk is a good source of protein (8 grams per cup), calcium (30% of our daily needs as adults), and vitamin D (45% DV – although it’s important to point out that cow’s milk is fortified with vitamin D so I don’t really think it should be praised for that). The thing is, there are plenty of other foods that contain these nutrients. If your child suffers from lactose intolerance or a milk allergy they are not going to develop rickets or osteoporosis (yes, it’s a pediatric disease with adult consequences) as long as they obtain enough of these nutrients from other sources. If you’re child just doesn’t like milk, or you choose not to serve them milk for whatever reason, they can still live healthy and productive lives.

One of the reasons that excessive milk consumption in children is an issue is that it tends to lead to insufficient consumption of other nutrients, specifically iron. Iron deficiency can lead to anemia which can be indicated by paleness, fatigue, decreased immune function. There is also the potential for poor growth and development as a result.

Good food sources of iron include: oat bran cereal, clams, spinach, beans and lentils, tofu, egg yolks, beef, and baked potatoes. Using uncoated cast iron cookware (especially to cook acidic foods such as tomato sauce) can also increase iron consumption. Consuming vitamin C containing foods (such as citrus fruits, peppers, and tomatoes) with iron-containing foods can also increase the amount of iron absorbed.

Good food sources of protein include: tuna (and other fish), poultry, meat, beans, legumes, yoghurt, tofu, nuts, eggs, even grains.

Good food sources of calcium include: yoghurt, fortified orange juice, many cheeses, spinach and other dark leafy greens (kale, broccoli, asparagus), tinned salmon (with bones) and sardines, fortified cereals, and tofu.

Good food sources of vitamin D include: egg yolks, fatty fish (herring, eel, salmon, sardines, tuna), and fortified cereals.

There is a huge proliferation of “milks” on the market these days. You’re no longer limited to cow’s milk or soy milk. There’s almond milk, coconut milk, sunflower milk, quinoa milk, hemp milk, rice milk… The choices can be overwhelming. The first thing you should check for is added sugar. No need to consume any more sugar than we already do. Next, check your labels to ensure your “milk” is fortified. Finally, check for unwanted ingredients like added oils. Beyond those tips, go for what you (or your child) actually likes. With all the options available you should be able to find one that will be both pleasing to your palate and provide the nutrients you need.

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Vitamins: Natural weight loss pills?

A friend alerted me to this article on the Livestrong website. While, the site does have some useful and accurate information, this article on weight loss vitamins is not. It suggests the following vitamins are useful for weight loss: B vitamins, choline, calcium, and chromium. Sorry to say it, but if taking vitamin supplements promoted weight loss then there wouldn’t be so many people struggling to lose weight.

B vitamins play an important role in energy metabolism. This does not mean that they increase energy expenditure and promote weight loss. The need for B vitamins may increase with high levels of exercise; however, most of us get plenty of B vitamins from our diets. The B vitamins are water soluble which means that there’s not a great risk of toxicity from taking supplements but it also means you’re just going to pee out any excess. Unless your diet is inadequate or you’re an alcoholic, there’s no reason to take a B vitamin supplement. There is no evidence that supplementation with B vitamins will promote weight loss.

Our bodies produce choline. However, it appears that we do need some dietary sources as well. Most people consume more choline than we need (RDA is 550 mg for adult men and 450 for adult women, and we generally consume 700 – 1000 mg a day). Choline is associated with learning, memory, and muscle control, not weight loss. The upper level for choline is 3.5 grams per day based on low blood pressure and a fishy body odour. High doses can result in vomiting, salivation, sweating, and negative GI tract effects. As choline is widely available in foods, and there is risk associated with excessive intake I would advise against taking a supplement without consulting with your doctor or dietitian.

Calcium is important for bone and tooth growth and strength as well as muscle contractions and other cell functions. Many of us don’t get enough calcium in our diets. However, there is no reason to believe that consuming a calcium supplement will cause weight loss. You may want to consider taking a supplement if you’re not obtaining enough calcium-containing foods, although it would be better to aim to consume more calcium-rich foods like canned fish, leafy green vegetables, tofu, milk or fortified milk alternatives, cherries, and beans, etc.

Less is known about chromium than the other vitamins and minerals mentioned in the article. Most of us consume enough chromium in our diets. Chromium deficiency can lead to impaired glucose tolerance which increases the risk of type 2 diabetes. There is little information about chromium in foods. The most reliable dietary sources are: meats, whole-grains, egg yolks, mushrooms, broccoli, nuts, legumes, and beer. The most common form of chromium in supplements differs from the form found in foods and can lead to the production of harmful free radicals. Definitely doesn’t sound like a supplement I would want to take.

If you want to lose weight you’re going to need to make changes to your diet. Supplements are not the answer.

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Eat your granola bars to get your calcium

I recently saw a commercial for Quaker Chewy Granola Bars. The tagline was “ten grams of whole grains”. I love how advertisers can insert essentially meaningless information like that to make their product sound healthy. Whole grains are healthy; therefore, these granola bars must be healthy. But what does that information even mean? Well, it means that out of the total 24 grams each granola bar weighs, ten of these grams are composed of whole grains. “What are the other 14 grams?” you might ask. Well, they’re things like various forms of sugar (i.e. brown sugar, sugar, corn syrup, invertsugar, corn syrup solids, and molasses but don’t worry, they no longer contain high fructose corn syrup!) and oil.

When I visited the website to find the nutrition information for these granola bars I also noticed a little factoid stating: “Good source of calcium (per 40 grams)”. Why they can get away with putting facts for amounts larger than the serving size is beyond me. You would have to eat nearly two chewy granola bars to get that “good” source of calcium which is really only 16% of the average person’s daily recommended intake. You would then also get about 3 teaspoons of sugar. Call me crazy, but I don’t recommend eating granola bars to get your calcium.