Today marks the tenth year of celebrating Dietitians Day in Canada. It’s designated as such to shine the spotlight on my fellow dietitians as regulated health care professionals, committed to using their specialized knowledge and skills to translate the science of nutrition into healthy and delicious fare while at the same time, supporting healthy living for all Canadians.
Enlightened eating can certainly be a daunting task these days. Not only are we being bombarded by nutrition advice from self-styled experts and celebrities who want to sell you the latest cure-all and promote dietary strategies with no basis in science but we’re also getting inundated by the media about research from reputable journals. The problem here is that the studies that grab the headlines are not the same old boring stories we’ve long heard about but ones that go against the grain.
I’ve written about too many of these lately. The last one was about breakfast and its impact on bodyweight. But the researchers didn’t even look at what people were eating and they, themselves, noted that the quality of the data was low.
Yet the study was published.
Which leads me back to Dietitians Day. Research concerning nutritional issues is all too frequently reported in the media without any context. This is where the expertise of a dietitian comes in. We can look at the research and evaluate how the studies are done and just how much credence we should be putting in that particular research.
The most recent study on eggs is a perfect example.
If the latest barrage of headlines on eggs and cardiovascular disease has you feeling as though your brains are scrambled, you’re not alone. It might have you believing that eggs are bad for you – yet again.
Or are they?
Before you consider eliminating eggs from your menu, you might want more information on the study details. As well, it’s key to keep other research on eggs in mind.
The study linked egg consumption to a higher incidence of cardiovascular disease incidence and death from all causes. While the research did include more than 29,000 adults over a follow-up of 17.5 years and looked at the incidence of cardiovascular disease, it’s important to understand how the investigation was conducted. The information on what the participants eat was collected using self-reported dietary recall. This meant that the participants had to note their usual diets including how often they ate certain foods (Can you remember all of last week’s lunches?).
This method of compiling information about what people eat is one that has been highly criticized as being quite unreliable. Then consider this: the dietary information was collected just once at the start of the study – just once! No dietary information was collected through the 17 1/2 years of the study.
The authors of the study also point to various limitations in their work. They acknowledge the issue of possible measurement errors due to obtaining self-reported diet data.
But the bigger limitation they point out is that the research is observational and does not show cause and effect.
Here’s an example of an observational link or association. The summer is the season where the most hot dogs are consumed. And while you might think that winter is the season where most car accidents occur, you would be wrong. According to statistics, there are more accidents in the summer. So using the observational links, you could think there is an association between eating hot dogs and your risk of having a car accident.
We all know, though, that kind of association is nothing but baloney.
Clinical research, on the other hand, where scientists compare similar groups of subjects under controlled conditions, such as specific diets for a period of time, and then look at the outcome, can possibly predict cause and effect. Check out this clinical trial on eggs in those with diabetes.
Yet when it comes to nutrition research, the fact that it may be observational study findings is usually left out of the story. We’re are often left believing they are cause and effect. That’s where dietitians come in. While we are sometimes criticized for promoting balance and moderation, if that’s what the scientific evidence shows, that’s what we’ll be saying.
And that’s why I am saluting my colleagues for jobs well done.
Enlightened Eater 
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