The confusion surrounding nutrition

How do you handle the ever-changing science of better eating and well-being?

It seems as though nutrition news is ever-changing. Official guidelines say one thing about what to eat, but diet books and bloggers offer different advice — often to remove healthy foods from your diet for no credible reason. If you are confused about the correct nutrition information to follow, you’re not alone. Even I, a dietitian, get tripped up with new studies that question my beliefs. It makes you wonder, is nutrition science worth listening to at all?

With that in mind, I interviewed Dariush Mozaffarian, cardiologist and dean of the Friedman School of Nutrition Science and Policy at Tufts University in Boston, who recently co-wrote a paper on this topic.

WE TAKE IT TOO PERSONALLY

It may seem as if nutrition science is all over the place, but that perception is not reality, Mozaffarian says. The progress in this area is consistent with the pace in many other scientific fields but because nutrition is so personal, people internalize the messages in a way they wouldn’t in other fields.

“If you learn in physics that there was new research about a black hole, you may say, ‘Oh, that’s interesting,’ but you don’t change your habits because the science has changed,” Mozaffarian said.

That’s different in nutrition, where we hear a news report about a food we love and we alter our meal choices because of the new information, even when the results of the study don’t justify those changes. Consider the person who, upon hearing gluten can make some people sick, starts avoiding wheat. Or someone who switches to coconut oil based on one study, when the olive oil they formerly used is much healthier.

It’s common to experiment with fad diets because of something we hear at the gym or read in a magazine. But that’s not science. The “science” of nutrition science has been diluted. We have to remember that it is in fact a science, and we need to have people with expertise discussing it.

“Probably the biggest problem is that everyone feels that they can be an expert on nutrition,” Mozaffarian said.

So think critically about where your nutrition information comes from before you make dietary changes. Misguided advice from non-experts doesn’t mean real nutritional science is inaccurate.

WE JUMP ON EACH NEW STUDY

Nutrition scientists have made amazing advances. In a span of just 50 years, researchers have gone from focusing on single nutrient deficiencies (such as vitamin C and scurvy) to unravelling complex connections between nutrition and chronic disease. In the science world, that’s considered rapid.

Sometimes, a one-off new study you hear about in the news may not mesh with the U.S. Department of Agriculture’s tried-and-true Dietary Guidelines (or, for Canadians, Health Canada’s equivalent requirements), which leads to more confusion. Studies are published weekly, but policy guidelines change every five years. What should you rely upon? Mozaffarian said he doesn’t think the public should change its dietary behaviours based on single studies, nor should policies be based on single studies.

WE CAN’T GET CONSISTENT GOVERNMENTAL ADVICE

Another major contributor to the public’s nutrition confusion is that there’s no unified central home for federal nutrition policy, Mozaffarian said.

For Canadians, in addition to the Canada Food Guide from Health Canada, there’s the Canadian Food Inspection Agency for food labelling; Public Health Agency of Canada’s Disease Prevention and Control Guidelines; Dietary Reference Intake tables, also from Health Canada; and more.

“I think it’s a lost opportunity that these relatively separate agencies don’t always overlap,” Mozaffarian said.

Mozaffarian hopes universities will do more to help minimize the confusion and would like to see more nutrition researchers intersect with policymakers, the food industry, the media and celebrity influencers to deliver evidence-based messages to the public.

Science is influencing policy, which is good news. The most recent USDA’s Dietary Guidelines have shifted from the old advice of meeting nutrient targets to a sharper focus on developing better dietary patterns as a whole.

This change is consistent with what nutrition researchers are working on.

GETTY IMAGES/ISTOCKPHOTO Be careful with reports about nutrition, warns cardiologist Dariush Mozaffarian, who urgers people to think critically before making a dietary switch, such as choosing coconut oil over olive.