This is part two in a four-part series inspired by the TEDTalk “Battling Bad Science“.
Part 2: Don’t Buy the Headlines.
Nutrition and its impact on health is a hot topic. Numerous newspapers and magazines have health, food, or nutrition sections (or a combination of these) and we always share the best of these with you at the end of the week in our TGIF. We know the dietary choices we make affect our health over the long term. The food industry and the media can often exploit this realization by playing on peoples’ emotions: fear of developing a disease, hope that a child with autism can be cured by diet, frustration with weight gain or desperation to find a dietary treatment where traditional medicine fails.
Canadians seek nutrition information from multiple sources, most commonly food labels (67%), the internet (51%) and magazines/newspapers (43%) (1). There can be some great information buried in these sources and recent findings are often presented in a way that is more user friendly than the traditional scientific journals. Not to mention that many of the scientific journals require steep access fees and are not available to the general public. The question then becomes how do you read the headlines with a critical eye?
Here are a few tips:
1. Sensationalism. Is the headline worded in a sensational manner? Does it have an emotional hook that will quickly grab your attention? Does it seem improbable or unlikely?
“Wine chemical may bring cancer hope.” It doesn’t get more emotionally-loaded than cancer + hope. Once again we see in vitro cell culture results being touted long before any human trials have been done.
2. Go to the source. Look for the original source and try to track it down. If available read through it carefully. Whenever someone chooses bits and pieces to publish or a segment to quote there is a chance you’re not getting the whole story.
“Menu nutrition labels don’t change habits.” Buried within the text is the fact that only ONE fast food chain in ONE community was focused on. Results were compared with another “control” community based on calories-per-transaction.
A recent Toronto-based study investigating the impact of diet on cholesterol is another great example. The article discusses the added benefit of increasing cholesterol-lowering foods rather than simply reducing saturated fat. Sounds great, right? What they fail to mention is that all of the groups were following a VEGETARIAN diet!
3. The subjects. Who were the participants of the study? Were they even people? What were the characteristics of these people? Something that works in healthy adults might not be appropriate for children, women who are pregnant or an individual with a heart condition.
“Fructose can trigger cancer cells to grow faster, study finds“. Adding “in petri dishes” to the end would have made this headline more accurate.
4. Numbers matter. How many people participated in the study? How long was the study? What dose or amount of food was used? A report that a food or health product consumed in four times the amount any person ever would eat should be interpreted with caution.
While we are never going to argue with eating more veggies and fruit, a study with only 14 participants is by no means definitive and results cannot be applied to the general public.
5. The purpose. What is the goal or purpose of the publisher? Is it to sell more papers, sell a product, lobby for a cause, etc.?
My personal favourite for illustrating bias – the fine print tells you that their funding comes from members… who so happen to be dairy and cattle/poultry farmers. No wonder they hate soy so much!
6. The “expert”. Where is the information coming from? Do they have the expertise to comment on the topic? Do they have any conflict of interests? Do they stand to benefit from their comments?
When your expert was trained at a non-accredited and subsequently shut down institution (!), like Clayton College of Natural Health, does the PhD still count? You would be surprised at how many of these “experts” are well-known and continue to be published in magazines, websites and books.
When you read the popular media with a critical eye you benefit from the research of others without risking misinformation. Enjoy the TGIFs and always read with caution.
1. Goodman S et al. Use of nutritional information in Canada: national trends between 2004 and 2008. J Nutr Educ Behav. 2011 43(5): 356-65.