Gremlins, Goblins, and Nutritional Hocus Pocus

I'm postponing the Challenging Nutritional Myths series in honour of Halloween (it will be back on Monday).

One might think that because I'm a dietitian Halloween upsets me because kids get a lot of candy and other junky foods. Not so...in fact I doubt that an otherwise healthful diet will be thrown off course by one night of excess, providing parents have sense enough to dole out the remaining treats judiciously. The night of tricks and treats and disguises does get me thinking, however, of the many ways in which the public can be fooled about food and nutrition.

For openers, let's consider the goblin that keeps raising its ugly head: the raw food movement. Yesterday I discussed the pitfalls awaiting those who opt for raw milk, but the raw food movement goes way beyond that. There are countless examples of ways in which this notion is flawed: wheat, soybeans, kidney beans, all of which are processed (and must be) before we eat them. Of course, there are those who feel that if they don't heat a food, then it therefore is raw and unprocessed.

The biggest argument against consuming food in its raw form is, naturally enough, bacterial contamination. Even sushi and sashemi lovers are taking a bit of a risk unless they know the fish is absolutely fresh and the chef knows what he/she is doing. If the raw fish is frozen prior to preparation, then the threat from parasites and worms (nematodes) is removed, but there is still a threat from viruses that can lead to hepatitis A and the Norwalk virus. Bacterial risks include listeria and salmonella among others. Raw meat is a whole other ball game. Lovers of steak tartare are usually safe, but one never knows. As for raw poultry and raw pork...puleeze.

The argument in favour of raw food is that there is significantly less loss of vitamins. This is true, up to a point. But carrots, for one example, yield more beta-carotene when they're cooked than when eaten raw because the cooking causes cell rupturing which yields more of the vitamin. Now, the greater amount of beta-carotene in the cooked product can be measured in nanograms, but still it shows that the raw argument doesn't always hold water.

Another gremlin that is reinforced by thoughts of Halloween is the notion of "too much of a good thing". We all know by now that a bit of dark chocolate might be just what the doctor ordered, but too much can pose a serious problem. There are other similar situations in the world of nutrition, none of which are likely to be doled out on Halloween. I'm thinking first about vitamin/mineral supplements. I doubt that even nutrition fanatics will hand out chewable vitamins as a treat for tricksters, and if your diet is really ghoulish then you should consider following your country's food guide. Until that happens, it probably won't hurt to take a multi-vitamin pill once a day. The problem arises when people are convinced that they need particular vitamins or minerals in huge amounts. Even as seemingly innocuous a nutrient as beta-carotene has been shown to be risky when large doses are consumed. Ditto for vitamin E, zinc and selenium to name a few. The fact is, we just don't know what excessive intakes of these nutrients by themselves might do to us. A word to the wise: don't fall for those tricksters who try to convince you about "health in a bottle". Good health is partly dependent on good eating and appropriate amounts of exercise.

The next perhaps surprising entry in the goblin category is juice. Who would ever have thought that a dietitian would be cautioning people against excessive juice consumption? Well, weirder things have happened. As it turns out, some folks have gotten carried away with the idea that juice is a good thing. Which it is...as long as you don't overdo it. The main problem with juice is that it can pack a heavy caloric wallop and it lacks the fibre of the original fruit or vegetable from which it was extracted. Juice is a quick way to get a lot of nutrients, but the whole fruit/veggie is still your best bet.

Wrapping up this ghostly, ghastly gallery is the muffin and cupcake...disguised as nutritious nuggets. Remember this: most cupcakes and muffins are simply fat little cakes. Just because a couple of blueberries find their way into the product doesn't make it healthful. Also, we need to bear in mind that the majority of commercially prepared muffins and cupcakes use shortening as their fat source. I'm sure you don't do this at home, but if so, please opt for a non-hydrogenated fat for your baking. On top of all that, the store-bought muffin or cupcake is often so big you need a fork-lift to get it off your plate. Mini-muffins/cupcakes are the way to go...might even make a good Halloween treat if people weren't scared that there were some unwanted items slipped inside!

So that's all my scary news for this time. A big BOO to all the nutrition misinformation out there. You can still count on bobbing-for-apples as a great Halloween tradition!

Challengin Nutrition Myths: Myth # 4

Myth # 4: Food today is full of dangerous chemicals.

All foods are made up of chemicals. You might be surprised to see the list of chemicals that make up a perfectly natural apple or orange. Certain processed foods have small amounts of approved chemicals added to increase their safety, shelf-life, palatability, appearance, texture, etc. What some folks have forgotten is that "it's the dose that makes the poison"...in other words, it's the amount of most substances that will determine whether or not they are toxic. In small amounts approved preservatives and additives are not harmful and are infinitely preferable to mould, rancidity and bacterial invasion.

Most countries have laws that are very strict in terms of just what and how much of a particular additive or preservative is permitted to be put in a food. The testing for safety of additives and preservatives is extremely thorough as well. Unfortunately foods rot, bacteria invade, and insects attack; nature is not always as benign as it's cracked up to be.

For whatever reason some people seem more comfortable with an illness delivered by nature than with the scare of man-made chemicals. The nonsense of drinking raw, unprocessed milk is a case in point. Despite overwhelming evidence of the risk of bacterial contamination in raw milk, some people would consume it in preference to pasteurized milk because of a sense that it is more "natural". Similarly there are those who argue against the fluoridation of drinking water even though this practice has been shown to be of benefit to teeth and safe in the amounts used. Another fear is of irradiation. While this method of food preservation could be argued to be unnecessary in western countries since we have other, effective methods, there are great numbers of people starving in third world countries while donated food rots or falls victim to insects. They could benefit greatly if this food were to be irradiated.

Yes, we want to be vigilant about food safety, but at the same time we should be receptive to advances in food technology. And remember the alleged conversation between two cavemen: "How come everything we eat is 100 percent natural, yet our life expectancy is still only 23?"

Challenging nutrition myths: Myth # 3

Myth # 3: Bread and pasta are fattening.

Nothing is "fattening" until you consume enough to exceed your caloric requirements for the day...then, everything is fattening. Carbohydrate, which bread and pasta are mostly, contains four calories per gram, as does protein. Fat, on the other hand, yields nine calories per gram, giving it more than twice the energy value of the other two macronutrients. Because of fat's greater satiety value (it makes you feel full longer) it's been argued that fat in the diet helps to keep you from over eating. It's sort of a "which came first, the chicken or the egg?" kind of conundrum, but in any event, the spreads and sauces one uses on breads and pasta definitely heighten the caloric ante.

What's equally, or perhaps even more important than calorie content in the choice of a starch like breads, pasta, cereals and rice, is the amount of fibre that goes along with it. Pasta, for example, has become very popular and that's good since it's an excellent source of complex carbohydrate with a relatively low glycemic index (we'll go into that later). Unfortunately, most pasta lovers consume the white, refined variety, which is basically the nutritional equivalent of white bread. Not that white bread is worthless, mind you, but in the refining process the flour loses most of its fibre and a lot of important trace minerals and vitamins. "Enriched" flour has four B vitamins and iron added back, but it's still not as nutritious as the genuine article. Some enriched flours add ascorbic acid as well, but I wouldn't count on it to protect you from scurvy.

Your best bet from the world of carbohydrates is anything that's brown (alright, beige if you're going to be picky): brown rice, whole grain breads and cereals, whole wheat spaghetti. The latter is perhaps an acquired taste, but most people who try it genuinely like it. The comment is usually about the pleasant, nutty taste of whole grain pastas. Now, of course, there are "smart" pastas on the market, so there's really no excuse for having the completely refined kind.

A discussion of carbohydrates wouldn't be complete without addressing the issue of sugar. Many believe that sugar is responsible for a lot of health problems and certainly tooth decay fits into this category. For those who brush their teeth after sweet treats, indeed after any meal, then a moderate amount of sugar to heighten the enjoyment of food is acceptable. It might even help us to eat a healthful food that isn't terribly palatable on its own. Sugar doesn't CAUSE hyperactivity, hypoglycemia, or diabetes, but people with the last two conditions are wise to avoid it. Having said all that, there are great sugar replacements now available, and if sugar is causing you to exceed your caloric intake, or you are diabetic, have hypoglycemia or elevated triglycerides, then choose them. A number of products are available allowing you to choose from sucralose, aspartame, and (in some provinces/states) stevia, with, I'm sure, several more to come.

Challenging Nutrition Myths: Myth # 2

Myth # 2: Cholesterol-free foods are a more healthful choice.

Not necessarily. Some foods that have absolutely no cholesterol may be loaded with calories, sugar and salt. Conversely, eggs contain cholesterol in the yolk (no big deal for the average person)and are also very rich in many important nutrients. They can be a valuable part of most people's diet. Watch out for baked goods made with hydrogenated vegetable oils...whether you bought them or made them in your own kitchen. These foods may very well have no cholesterol, but lots of trans fatty acids. I hope a special place is reserved in Hell for companies that brag "no cholesterol" when their product didn't have it in the first place...products like potato chips and peanut butter..

Speaking of fat and cholesterol, some people have concluded that the appropriate way to avoid these substances is to eliminate red meat from their diet. Bad move. It's certainly wise to avoid excessive intake (of anything)but just because nobody needs a 16 ounce slab of meat hanging off their plate, is no argument that therefore no ounces is a better idea. The minerals found in red meat, especially iron and zinc, as well as many vitamins, make it a perfectly healthful choice when consumed in moderation.

In a similar vein, some folks have bought into the notion promoted by some popular, though ill-informed, diet books that milk and milk products should be avoided. While it's true that whole milk and whole-milk products like cheese and yogurt contain fat and cholesterol, this poses no problem when consumed in normal amounts and when the rest of the diet is reasonably controlled for calorie content. Of course, one can choose low-fat or no-fat dairy products and still obtain all of milk's valuable nutrients...especially calcium and riboflavin. The down-side of opting for fat-free milk products is that a very important substance is thereby rejected: conjugated linoleic acid. CLA (the acronym for conjugated linoleic acid) has been shown in countless animal studies (and some human studies as well) to be anti carcinogenic and possibly anti atherogenic. It could be simple coincidence, or more telling than that, but as the intake of dairy fat (and the fat of all ruminant or cud-chewing animals) has gone down, the incidence of cancer and coronary artery disease has gone up. Compounding the problem is the fact that the intake of linoleic acid (found primarily in vegetable oils) has also sky-rocketed along with the incidence of these diseases. Linoleic acid (an omega-6 fatty acid) is a known cancer promoter and of particular importance is the ratio of omega-6 to omega-3 (found primarily in fish oils). For more on this topic see my blog dated June 19, 2009.

The upshot of all this, is that it's wise to concentrate on your overall caloric intake, but don't make the mistake of eliminating any important food group in so doing. Let moderation be your guide and take advantage of the many calorie-reduced and calorie-free products on the market. Just be sure that a product labeled "fat-free" hasn't replaced the fat with sugar, resulting in as many or more calories than the original product had in the first place.

Challenging Nutrition Myths

Myth #1: It costs more to eat nutritionally.

There's no getting around it--times are tough. It's enough to break your bank book and your heart, the latter both figuratively and literally. One of the major concerns of dietitians these days is that in an attempt at saving money on the grocery bill, you and your family may be eating your hearts into an early grave, choosing low quality foods to fill up the old cupboard. Well, in the words of Willie Nelson, "It don't have to be that way". You can shop economically and still select healthful foods.
The above myth is definitely false. In fact many of the least nutritious foods are the most costly items in a grocery cart. Yes, attention needs to be paid to buying produce in season and avoiding paying the manufacturer's exorbitant prices for doing your meal preparation for you, but basic, nutritious foods are usually the least expensive. Here are some tips to help you get the biggest nutrition bang for your grocery buck:
* Plan a weekly menu and prepare a shopping list (largely based on store specials). This will help cut down on impulse buying. Also, by planning ahead you can plan for leftovers AND make use of what you already have on hand.
* If it's true that time is money, then many convenience foods deserve a place in our busy lives. Some, however, cost a whole lot for saving very little time and/or effort. Quick rice and pancake mix are two examples.
* Be aware that private label food products are just as nutritious as the "big name" brands and usually cost considerably less.
* Treats deserve attention, too. It's easy to say that if the budget is strapped we should cut out the fun foods, but that would be ignoring the important psychological component of food. Treats can be selected with an eye to nutrients as well: popcorn with some grated cheese sprinkled on top; frozen yogurt; homemade pizza; and, naturally enough, homemade cookies with healthful ingredients like raisins, oatmeal and nuts.
* Remember that the less expensive cuts of meat contain the same important nutrients as the pricey ones--but sometimes more fat and bone. Calculate how many servings you can get from a pound or kilo and do your price comparisons from that perspective.
* In general, most of your starch or complex carbohydrate choices are more nutritious and less expensive when they are unrefined or the whole grain variety. Of course, if your family won't eat it, then it's money down the drain. You might start by incorporating some whole grain into the white variety and gradually increasing amounts.
* If you have any extra money on hand, buy large quantities of staple items (canned goods, cereals, rice, pasta, etc.) that are a really good deal, If you have a freezer take advantage of meat, poultry and fish sales.
* This is an oldie, but still goodie: eat before you shop. If you go to the store hungry, your shopping list doesn't stand a chance.
* Bear in mind that the milk products group is about the most nutrient dense available...more nutrients, less money. For cooking and baking consider using powdered skim milk (if you can still find it) and canned, condensed milk.
* Day-old baked breads, rolls and the like are usually marked down but are as fresh as if you'd bought them yesterday and stored them at home. If you have enough freezer space, buy enough of these marked down baked goods for a week at a time.
* Freeze the heels of breads and slices that are too dry for ordinary use (throw out moldy ones). Crushed, crumbed or cubed and toasted they make great toppings for casseroles, coatings for meats, croutons for soups/salads, and stuffing for turkey.
* If bananas become over-ripe don't assign them to the garbage can. Instead, put them in the freezer; they'll turn black alright, but they'll be great for banana bread, muffins, etc.
*Baked beans are a great occasional alternative to meat. Canned beans are certainly acceptable (watch out for added sugar and salt). If time is not a problem, consider baking large batches in one big effort and freeze in smaller units for later use.

More nutriton myths will be debunked on Monday. Happy week-end.

Are you allergic, or simply intolerant?

As old Lucretius (95-55 B.C.) was fond of saying, "one man's meat is another man's poison". I don't know if Lucretius bit into a nut to which he was allergic, but he was definitely on the right track. Foods that are mother's milk to most of us, may dreadfully discomfit (sometimes even kill) an unfortunate few. Just how few is the subject of controversy as the idea spreads that a variety of symptoms (not just those of classical allergy) are caused by individual hypersensitivity to certain foods or, more correctly, substances in those foods. Many are convinced that food sensitivities have become more common and that food processing has something to do with it. The media, various unorthodox practioners and some groups of lay people have spread the "news"--and somewhere in the hornet's nest are a few facts concerning immunology, food technology, and quackery.

First, let's get the terminology straightened out. To help with this I've turned to the British Medical Journal. The words describing food sensitivity are imprecise and are often used to mean different things; surely the Brits can simplify matters. According to them "food sensitivity" can be used to describe a reproducible unpleasant reaction to a specific food or ingredient which one person gets but others don't. Right away we can see that this definition leaves out food poisoning; Socrates wasn't suffering from food sensitivity when the hemlock did him in. Rather, it was the insensitivity of his enemies, but that's another story. We might say, however, that Socrates suffered the ultimate adverse reaction to food.

"Food allergy" is commonly used as a broad term to explain physical reactions to certain foods but, technically speaking, should be confined to immunological reactions--a situation involving the immune system, specifically immunoglobulin E. "Food intolerance" covers a wide range of responses to food (not related to the immune system) including the lack of an enzyme (e.g., lactose intolerance in which the enzyme lactase is missing or deficient), an irritation (certain spicy foods), or complicated reactions such as gluten intolerance in people with celiac disease.There is even a psychological food intolerance covering psychosomatic reactions which don't occur when the same food is given in an unrecognizable form.

Diagnosis of food senitivity (allergy or intolerance) is a piece of cake when there is a characteristic early response to a food that is eaten at least occasionally. The patient often notices the association and tells the doctor the diagnosis. The prescription is easy: if you're allergic/intolerant to something, don't eat it. Sometimes, however, the guilty substance may be "hidden" as an ingredient in a manufactured product and might even have a name that isn't easily recognizable or readily identifiable as the offending material. Also, if you're sensitive to a whole raft of things, you could be courting nutritional deficiencies by avoiding them all...so a consultation with a registered dietitian is definitely in order.

A diagnosis becomes more difficult if the clinical reaction is delayed or varies or doesn't always happen. Such a reaction is also made more difficult to judge if someone else has already incriminated a food on circumstantial evidence (post hoc ergo propter hoc: after the fact, therefore caused by the fact) or because of a "prejudice" toward that food. Skin tests are used for suspected allergies and along with the patient, or in the case of a child, the parent, acting as a detective, the truth can usually be ferreted out as to which foods lead to which predictable reactions, and the diet is adjusted accordingly. The various strategies that can be used to identify the culprit(s) include: a diet diary in which a list is kept of all foods eaten and symptoms noted (this method is open to subjective bias, isn't suitable if the reactions are serious, and is difficult to interpret if the responsible agent is present in several foods). Suspect foods can be eliminated for about a week at a time but this has the same drawbacks as the aforementioned. An elimination diet followed by reintroduction of foods one by one involves the removal (for two to three weeks) of all foods that commonly provoke sensitivity reactions. One food is then added back every seven days. In an elimination diet (one of several) the meat least likely to cause a reaction is lamb; the least "offensive" cereal is rice; for vegetables it's peeled potatoes, carrots and lettuce, and in fruits it's pears. Water and sugar is permitted ad lib. Obviously, there's a risk of nutritional deficiency if this is carried on too long--and such trials should really be conducted with the guidance of a registered dietitian.

More exotic food sensitivities, but nonetheless a real pain to the sufferers, include favism, a type of anemia that results when particular people eat fava (broad) beans; "bitter lemon purpura" caused by the quinine in bitter lemon, and, of course, "Chinese restaurant syndrome"--a sensitivity to monosodium glutamate. Whatever the category in which they're placed, food sensitivities are a real menace; if you're not a victim, be thankful

Ordinary veggies top nutrition chart

Magazines today are full of lists of "super foods"...usually naming 10 of these potential miracle workers. Most lists include berries, fruits and vegetables, whole-grain products, milk and yogurt, dried beans, fish (especially fatty fish)and greens of all sorts. Human beings seem to be fascinated by lists of the best and the worst...probably rooted in David Letterman's top ten list. In the nutrition department, other than the aforementioned magazines, lists haven't figured too prominently; one can't even give an award for the best food, since no one food could keep you alive all on its own. Milk comes closest to being perfect (and it is, for infants), but is lacking in vitamin C, iron and fibre.

Somebody had the bright idea of looking at three particular nutrients--beta-carotene, ascorbic acid (vitamin C) and fibre and coming up with a list of the top five foods normally consumed in the western diet, that will give you the best shot of a good dose of all three. Many people feel that they need to load up on these nutrients and increase their intake of wheat bran and vitamin supplements. That plan could possibly backfire since there are many more types of fibre than just the cellulose and hemi-cellulose found in wheat bran and because large doses of particular vitamins may wreak havoc with the metabolism of other nutrients. Moreover, concentrating on vitamin supplements may lead to a lackadaisical attitude toward a healthful diet and a neglect of other potentially helpful substances contained in food.

Anyway, it was thought to be a good idea to find out which veggies would pack the best nutritional wallop for all three of these nutrients (fibre isn't exactly a "nutrient", but let's not split hairs) so that folks would be helped in their choice-making. For example, bran is obviously loaded with fibre, but miserly in the vitamin C and carotene department; oranges are great for vitamin C, but really no big deal when it comes to carotene and fibre (although the whole fruit is a way better source than its juice). You get the picture. So, a little drum roll please: the five winners in the big-three contest are spinach, broccoli, carrots, sweet potatoes and peas. How's that for ordinary? And you thought good nutrition had to be exotic. A list of the best foods for minerals in the diet would be pretty short--only two: milk products and meat.

This notion of choices really hit me recently when I was watching a woman struggle with some choices at the deli counter. Her problem was deciding which her family liked best--macaroni salad or potato salad. It was all I could do to keep from butting in and asking her to consider the nutritional consequences of her selection but, ever mindful of my place, I kept quiet. But now I'll ask you: weigh the merits of the salad war. Given that all the other ingredients in the mixture are the same--the mayo, the onion, the seasonings, maybe a little chopped up celery, it boils down to a comparison between potatoes and macaroni. At half the calories, potatoes have five times the potassium and infinitely more vitamin C. For the same weight potatoes give you three times the fibre of macaroni or three grams versus one gram in an average serving of both.

That's not to say that you should always choose potatoes over macaroni, but it's something to consider when you are weighing your choices.

Egg-Marketing Strategy Meeting Divine

I like to picture God at a marketing strategy meeting (not that God had to work with a committee when He/She was dreaming up Creation, but that's how my mind works--besides who else would be on the committee, a couple of the top angels?)when the idea of the egg was proposed. The packaging of the egg had to be a bit tricky. Somebody would be opting for a square shape (so it wouldn't roll off the counter) and God (being such an animal lover) would have to urge consideration of the hen--imagine the squawking during the laying of a square egg. The, of course, the color. Eggshell has been done so much, one would chime in, how about indigo or magenta?. "No", God replies, "white, beige or brown--that's it. We have to keep costs down".

The structure and composition of the shell must have generated a heated discussion. Rubber would be suggested so the egg would bounce if dropped. "Not bad", thinks God, "but what about all those people who want to put ground egg shells in their coffee or ground them up for a source of calcium. Rubber would stink". God wins that one (was it ever in doubt?) and we end up with the shell making up about 11 percent of the total egg and consisting mostly of calcium carbonate. For very good reasons the shell is granular, hard, translucent and sufficiently porous to permit the embryo to breathe. Some of the rationale behind the structure include breaking strength, retention of moisture and carbon dioxide, and perhaps most important, reduction of susceptibility to bacterial attack. And this is where the genius of God shines through. Inside the shell are not one but two membranes that separate at the big end to form an air cell--which forms as the egg cools after being laid. Then, on each side of the yolk are two ropes, called chalazae, that anchor the yolk in the centre, still letting it revolve. And the yolk gets its own membrane as well--the vitelline membrane.

So far, so good, but the meeting bogs down a little. Someone is still nattering about the color. A junior executive type that God wants to encourage, maintains that if eggs can't come in designer colours they'd better be all white or people will think brown ones are more nutritious than the more anemic whites. Owing to a great faith in human nature, God makes a rare mistake (I know He/She'd be the first to admit it): "Nobody I'd create would be silly enough to believe that!". On a more serious note the committee moves on to the composition of the egg. "I know", cries one, "for people who are told to go on a low-cholesterol diet one day, let's put all the cholesterol in the yolk so people can still eat the white and not worry. "O.K." says God, "but I hope people won't get the notion that everybody has to avoid eggs because of the cholesterol". "Not a chance" pipes up the junior exec. "Besides, they can come out stamped 'dietary cholesterol has very little impact on serum cholesterol' and that should lay the matter to rest". Then the biology whiz kid at the end of the table becomes agitated. "Look", he says, "if the egg is going to have a label, then I want something explaining its high biological value".

Everybody's eyes but God's glaze over, sensing a biochemistry lesson coming down the pike. "The biological value", he drones on, "is an index of protein quality that reflects the percentage of absorbed nitrogen from dietary protein actually utilized by the body, measured under standard conditions". "Say what?" chimes a chorus of angels. "Protein foods containing optimal quantities and proportions of all the essential amino acids, as well as adequate supplies of non-essential amino acids, have the highest biological values", the Brain continues in a contemptuous tone. "And", he adds, "eggs top the list of all foods with a near perfect score".

"Well then", God declares, sensing a restlessness in the committee members, "let's wrap up. The egg will be oval-shaped, white, brown, or beige with cholesterol only in the yolk which won't harm the average person, loaded with protein, vitamins and minerals, and the yolk will be - green. They all file out. "Great meeting, Boss".

Vitamin supplementation: gilding the lilly

Quite a while back Time Magazine did a cover story on the exciting potential for vitamin supplementation in preventing , maybe even curing, various conditions. In the interest of the "equal time" policy whereby politicians of differing stripes are given equal opportunity to vent their spleen over the airwaves, it only seems fair to look at what the Time story, and many similar articles in the intervening time, didn't say.

To begin with, there's never been a study of normal, healthy people that showed lower disease incidence or increased longevity in the recipients of supplements. Not only that, the one study that looked at the effects of giving mega-doses of vitamin E to the elderly found a two-fold mortality rate in the pill poppers. This doesn't prove that vitamin E hastens one's demise, but it should at least give pause to the lemming -like rush to supplementation. True enough, there is some pretty good evidence that the incidence of certain cancers and some forms of heart disease might be reduced by large doses of some vitamins. On the other hand, there are equally convincing pieces of research showing that these same supplements may, in fact, increase the risk of other forms of cancer and heart disease. This is not, however, the kind of stuff about which people want to read.

As a for instance, let's consider the ten percent of the population that, often unknowingly, carries a gene for the condition heterozygous hemochromatosis, a.k.a. iron overload. Vitamin C, or ascorbic acid, enhances iron absorption, and for many people, especially those trendy folks who reject meat in their diet, this is a good thing. For the aforementioned iron overloaders, however, it can spell big trouble--especially if they're given to mega-doses of vitamin C. It has been confirmed that the deaths of three iron overloading athletes was due to prolonged mega-dosing with vitamin C. Another problem with Vitamin C supplementation is that it can ultimately spell big trouble for those people with a tendency toward oxalate build-up...the end result being the dread kidney stone. Again, not a majority of the population, but like the 40 percent chance of rain on the deluged picnic, if you're the guy with the kidney stone, it's a pertinent piece of information. In a similar vein, some people who take supplemental calcium (as opposed to getting it from dairy products, say) are setting themselves up for an attack of kidney stones since the supplement (and not the dietary form) can combine with oxalic acid and produce the resulting kidney stones...calcium oxalate.

Enough with vitamin C already...how about the encouragement for supplementation with beta-carotene? A little biochemistry lesson here: beta-carotene (found naturally enough in carrots) is a precursor to vitamin A, otherwise known as retinol. As with many situations in life, you can get too much of a good thing and a study done with beta-carotene is exhibit A. It had been observed that smokers with high blood levels of beta-carotene had a greater resistance to lung cancer. Aside from getting the smokers to quit (not the easiest task in the world) some researchers thought it would be great if just giving a beta-carotene supplement would do the trick. Unfortunately the experiment had to be stopped half way through when it was observed that those taking the supplement had a risk almost twice as high as the non-takers for developing lung cancer. Apparently high blood levels of beta-carotene might simply be a marker for something else that's going on in their diet or life...so back to the drawing board. We also know that excessive intakes of retinol (mostly through supplements) can wreak havoc on bone health.

All of this brings two things to mind: 1. For most nutrients it's safer to get them from food via a well balanced diet (vitamin D and fish oil being an exception, since most people don't have adequate dietary intakes); and 2. watch out for words like "may" and "might"...weasel words that are used to evade or retreat from a direct or forthright statement or position. If an ad states that vitamin X might help reduce your risk of a specific illness, remember that "might" carries with it the implied "might not".

Miss Muffet and other fairy tales are into nutrition

Those of you with an extensive literary background will probably recall that prior to doing battle with the spider, little Miss Muffet was eating not just her curds, but also her whey. If, in fact, your university courses gave you an in-depth understanding of macro-economics, but caused you to bypass Foods and Nutrition 101, you may not have the foggiest idea just what whey is anyway. Essentially it's this: when you curdle the protein in milk, it's the juice that's left behind. Fair enough--but is it "good for you"? You bet.

Research into the nutritional value of whey has emphasized its role in the retention of lean body mass and achievement of a healthy weight, but whey protein isolates (containing a minimum of 90 percent protein on a dry weight basis) are especially good sources of branched-chain amino acids like leucine. This amino acid is particularly important for stimulating muscle growth, of concern for seniors and athletes. No doubt it was the leucine that enabled Miss Muffet's quick getaway from the spider. Whey is an excellent source of many vitamins and minerals(especially potassium, so Miss Muffet was on the right track--maybe not about spiders, but certainly about nutrition. It's definitely worth your while to stir the whey back into your yogurt or cottage cheese, and to think about having a fruity milkshake with dried whey protein as one of the ingredients.

Other nursery rhymes contain ideas about nutrition as well. Jack Spratt (remember him: he could eat no fat; his wife could eat no lean)weighed in with his notion about fat intake. Insurance companies would probably put their money on Jack to outlive his wife, but the jury's not yet in on that one. In any case, I bet Jack had a heck of a case of fatty acid deficiency. Anon (the guy that wrote most of these fairy tales) probably didn't have a clue about linolenic and arachadonic acids...never mind that they wouldn't rhyme with anything. But the fact is that a fat-free diet like Jack's would give him, among other serious problems, a serious case of dermatitis.

For a real hard luck nutrition case we need look no further than Mother Hubbard. She goes to the cupboard looking for a bone for her dog and finds the cupboard bare. Never mind that bones shouldn't be kept in a cupboard anyway, most veterinarians recommend dog food over bones any day. Perhaps Mother Hubbard had eaten all the dog food. Who knows? Anon didn't provide much detail on topics of this nature.

In a somewhat lighter vein we have porridge--the subject of several nursery rhymes. You'll notice the operative term is porridge, as in rolled oats or oatmeal...nary a mention of oat bran. Do you suppose Goldilocks would have risked the wrath of three bears over a bowl of oat bran? And what about those folks that liked their peas porridge (whatever that was) in the pot nine days old. The very thought of nine-day old porridge is enough to drive even the most dedicated dietitian to a bag of Oreos.

For food and prejudice we need look no further than Higgledy Piggledy My Black Hen(she lays eggs for gentlemen). What is this--nutrition for the upper crust? One can just imagine those gentlemen arguing over dietary versus serum cholesterol. With any luck they realized that the egg is a superior source of nutrients and for the vast majority of the population dietary cholesterol (as found in the egg)is not a concern.

And where do you suppose the king was while the queen was counting all her money? He was somewhere (memory fails me) eating bread and honey. Sure, but what kind of bread? Nine grain? Cracked wheat? White enriched? Fairy Tales often raise more questions than they answer...but so do the charlatans operating so widely today. I wonder how they'd feel about four and twenty blackbirds baked in a pie?

What we know and what we don't know

Tacitus (AD 55-117) had a really neat way with words. Quoth he: omne ignotum pro magnifico. Gets right to the heart of the matter, doesn't he? For those of you too young to have taken Latin this translates as "anything little known is assumed to be wonderful". Oh Tacitus, what change a couple of thousand years have wrought!. Now, anything little known is not assumed to be magnifico, it's assumed to be stinko. Or, as you might have put it: omne ignotum pro malo. Another literary figure, Erica Jong, could have added some much needed insight had she tackled instead of "Fear of Flying", Fear of Food Stores, or Fear of a Lot of Food that's Found in Food Stores.

One of the most common questions put to a dietitian or nutritionist concerns not the potential that food has for mold or rancidity, but rather the "unknown" chemicals contained therein. "Unknown", of course, means not known to the general public; somebody knows what these chemicals are, but Joe Q. Public doesn't know who these somebodies are and likely wouldn't trust them if he did. Probably some government bureaucrat.

And the buzz word, or red flag for those concerned with politically correct or virtuous eating is the shibboleth "processed". Tacitus probably didn't have a word for processed, or if he did it didn't make it into my Latin book. If he was familiar with the "processing" concept, given the huge streak of common sense he no doubt possessed, he probably would have encouraged his countrymen thusly: "Yo, Romans, this processing is a pretty good trick, saves us more time for writing poetry, playing the fiddle and peeling grapes. But let's not get carried away with it. Remember that good, wholesome "real" foods are our best sources of nutrients, but a little approved and regulated chemical never hurt anybody." "in fact", he would continue, "your chances of being struck by lightening are a hundred times greater than harm from preservatives. And while we're at it, ease up on the wine; I suspect it's leaching lead out of our earthen goblets."

Of course, not having all the facts (being a great philosopher doesn't necessarily make one a great dietitian) Tacitus might have over-simplified things a bit. Suffice it to say, there are a number of factors that make food valuable to us: first and absolutely foremost are the nutrients it contains; second is the necessary freedom from the aforementioned mold and rancidity and bacterial/viral contamination; third is the pleasure thing--if a food doesn't please, all but the dedicated masochist will refuse to eat it; fourth, and a somewhat recent entry, is the convenience factor. Despite our nostalgic longing for the good old days when mother (yes, I said mother) spent all morning over a wood fire preparing the midday meal and then started on supper as soon as noon scraps were cleared away, convenience is a necessity for most, not a luxury. And yes, grocery stores carry convenience foods. Some of them are pathetic imitations of what Webster would define as food, but the majority, if chosen knowledgeably and served with choices from the four food groups, can contribute significantly to everyone's nutritional status. If you want to worry about something, watch out for foods with added sugar.

Sure, you need to be a chemist to understand some of the stuff on the ingredient list--but that doesn't make it bad. People generally believe what they want to. Or, as Tacitus might have put it: Fere libenter homines id quod volunt credunt...go figure.

Common wisdom meets pseudo-science

For some asinine reason, people have gotten the idea that any food or food habit chosen by early man or primitive tribes that have never run afoul of a white missionary, has got to be superior to any food or food habit that North Americans choose. As is usually the case when common wisdom meets pseudo-science, this conclusion is sometimes and somewhat off the mark. Oh sure, many cultures have stumbled onto nutritionally whammo combinations--beans and rice, macaroni and cheese--which is why they flourished, but often this was sheer happenstance.
Take the case of two African tribes living in close proximity, one experiencing a high incidence of xeropthalmia (a potentially blinding eye condition brought on by vitamin A deficiency), the other tribe virtually free of the disease. Nutritional anthropologists investigating the situation discovered that the disease-free group gathered seedling shoots (rich in vitamin A) in the early morning when there was just enough dampness from dew to produce them; after a few hours the seedlings withered. The neighbouring tribe was out of luck, high and dry, almost blind. Talk about the early bird getting the worm.
Analysis of primitive diets often reveal considerable wisdom--or luck--in the food choices of native peoples. The ancient Aztec custom of soaking maize in a solution of lime (calcium carbonate) before pounding it into meal has been shown not only to add dietary calcium but also to convert the niacin content of the corn into a biologically available form, thus preventing the niacin-deficiency disease of pellagra.By contrast, in the late nineteenth and early twentieth century, poor folks in the southern U.S. relied heavily on untreated corn as a staple in their diets (a grits-driven culture) and pellagra was rampant. Some decrepit mental institutions still exist there as monuments to major dietary blundering.

In South Africa, certain Zulu tribes had a strong taboo against drinking milk from cows that didn't belong to their own families. The upshot of that, of course, was that women who went to live with their husband's families drank no milk. The U.N.'s Food and Agriculture Organization (F.A,O.) had the brilliant idea of introducing powdered milk, which couldn't be identified as coming from any particular family's cows. While this could have had the unintended consequence of nobody in the tribe drinking milk because the origin couldn't be identified, common sense ultimately prevailed and "foreign" brides were soon drinking milk. In short order, and bucking the notion that new and processed is inferior to old and traditional, the nutritional status of many women and breast-feeding infants was greatly improved.

In present-day Colombia there is a problem that has nothing to do with drugs or dictators...it stems from the dietary custom of fava bean consumption. Fava beans. as it happens, are a very nutritional food, but contain a substance that is innocent enough on its own, but combines with the high nitrate content of the bean to make a carcinogenic compound. Colombians tend to eat fava beans several times a day; stomach cancer is quite common among these people. Another area of the world with a high incidence of stomach cancer is Japan, the home of a culture whose diet North Americans are encouraged to emulate. The culprit in this case is thought to be a high intake of smoked and cured vegetables and similarly treated fish.

Seasonal variations in the diets of different cultures often occur. The San bushmen are hunter-gatherers of the Kalahari desert of southern Africa. Great seasonal differences in rainfall and temperature lead to sharp fluctuations in the natural food supply. In the dry season people lose as much as six percent of their body weight and fertility drops markedly in San women. Birth data for neighbouring tribes on diets supplemented with cultivated food show a more even distribution of fertility. It's therefore been hypothesized that the diminished food intake of San women in the dry season sharply reduces production of the steroid hormones that maintain fertility. The seasonal fluctuation of the natural food supply provides a natural cyclical method of population control, while introduction of supplemental food resources may contribute to an increase in birth rates. Whether or not this is a good thing is subject to debate.

From a nutritional standpoint, it's simply bad policy to embrace a dietary practice based on the fact that it was the custom of dear old granddad, cro-magnon man, or a Tibetan monk. Nutrition is an evolving science and some day we may know with certainty the ideal diet. Till that day comes, you can't do better than your country's food guide.