In this further guest posting from Susan MacFarlane, RD, we discuss finding credible nutrition information. Nowadays, everyone seems to be an expert when it comes to nutrition advice: “Eat breakfast! Don’t eat until 12 pm!”; “Avoid carbs, they will make you fat! Fat makes you fat!”; “Only buy organic! Organic is a myth!” On top of these contradictory claims are flashy media headlines designed to instill worry and fear about the growing obesity/diabetes/autism/celiac/[insert alarmist health concern here] epidemic. As a result, many people live with health anxiety and are seemingly at a loss when it comes to nourishing their bodies.
So, what’s a health-conscious individual to do?
The key to keeping your sanity, and not getting pulled into a rabbit hole of collusion and conspiracy, is to become a savvy consumer of health information. What follows is the checklist I use in my nutrition practice to determine if the article I’m reading, or the claim I’m investigating, is credible.
Spotting Nutrition Misinformation
Where did you find the nutrition information?
The first stop on our journey to finding credible nutrition information is considering where the information came from. When most of us want an answer to a nutrition question, we turn to Google. And while the search engine uses a fantastic algorithm to find a relevant response to our question, it isn’t always the most credible. As a general rule, be cautious of blogs, magazines, and media outlets. While the information being shared in these sources may be credible, it tends to reflect one person’s opinion, rather than an objective and unbiased stance. (And yes, I recognize the irony of writing a blog post about finding credible nutrition, while telling you to be mindful of blogs, but bear with me.) In addition, pay attention to how the website ends; *.com websites are more likely to promote or sell products for profit, while *.gov (government sites), *.edu (academic institutions), and *.org (not-for-profit sites and health organizations) are more reliable and credible sources of nutrition information (1). A website that also provides several disclaimers, warning you not to use their information as medical advice and relinquishing all liability, is also a red flag. Lastly, look for the Health on the Net symbol at the bottom of the main page of the website. This not-for-profit organization promotes “transparent and reliable health information” by using a set of principles to standardize health information on the internet (2).
Who is the “nutrition expert” behind the claim?
To better appreciate what makes someone a nutrition expert, we need to take a detour to understand the difference between a regulated and unregulated health professional.
Regulated health professionals are governed by legislative colleges (for example, The College of Dietitians of Ontario) to ensure their members provide safe, professional, and ethical care. These colleges exist to protect the public and have disciplinary protocols in place to deal with complaints filed against their members. The only regulated nutrition professionals in North American are Registered Dietitians (RD, RDN); “Registered Holistic Nutritionist”, “Certified Nutritional Practitioner”, “RONP”, “RNCP”, “ROHP”, “RHN”, “CNP” are not the same as “Registered Dietitian” and do not indicate the person is a regulated health professional. Typically, these titles are used by those who have completed privately owned training programs that vary in length (most programs are 1-2 years) and rigor (3). On the other hand, dietitians hold a university degree in food and nutrition from an accredited university program, have completed 35-40 weeks of supervised practice, and passed a national examination to demonstrate competency and knowledge. Now, this does NOT mean that all dietitians are good, and all nutritionists are bad; rather, it simply reflects the degree of training and informs you, as the consumer, if the person you are entrusting with your nutrition care is liable for what he or she says.
So where do doctors fit in with all of this?
Although doctors receive extensive medical training, the amount of nutrition education they participate in is minimal. A study from 2006 (4) reported that medical students in the United States received an average of 23.9 hours (less than one day) of nutrition education during medical school. Thankfully, more doctors are appreciating the role of nutrition in disease and pursuing additional training. However, since this is not a requirement of all doctors, it’s a good idea to ask your doctor about the nutrition training he or she received in order to make an informed opinion on the advice that is being offered.
Does the nutrition claim sound too good to be true?
Then it probably is.
Losing weight or managing a chronic illness requires a long-term commitment to behaviour change. If there was a quick fix or a single supplement that could help my clients reach their health goals with less effort, I would be the first to recommend it.
What is the quality of evidence behind the nutrition claim?
Just because something is published in a scientific journal (even if it’s published in a peer-reviewed journal) doesn’t mean the information is sound or clinically relevant. “Publish or perish” is real phenomenon in the academic world and puts a lot of pressure on researchers to consistently publish articles, even if the articles don’t add anything useful to the scientific body of literature.
When it comes to nutrition claims, it’s essential to consider the type of evidence used to back them. A useful reference for interpreting the quality of evidence is the following hierarchy:
Meta Analysis: combines the results of multiple studies included in systematic reviews to come to a conclusion about the overall effect of an intervention (5).
Systematic Review: summarizes the results of controlled trials to determine the effectiveness of an intervention (6).
Randomized Controlled Trials: a study where participants are divided by chance into separate groups to compare different treatments or interventions (7).
Cohort Studies: compares an outcome (e.g. heart disease) among groups of people that are alike in many ways but differ in a certain characteristic (e.g. exercise vs. no-exercise; 8).
Case-Control Studies: compares two groups of people: those with the disease/condition (case) and those without it (control;9).
Cross-Sectional Studies: an observational study where data from a population is analyzed at one point in time (10).
What isn’t considered scientific evidence are anecdotes, testimonials, YouTube videos, that guy with 6 pack who promises results if you just avoid this one food, and gut feelings.
- Schiff WJ. Nutrition for Healthy Living. McGraw- Hill; 2008. Chapter 2: Evaluating Nutrition Information; p 28-49. Available online from: http://www.mhhe.com/nutrition/schiff1e/schiff_ch02.pdf
- Team HON. HoNCode Certification. 2018 May. Available from: https://www.hon.ch/en/certification.html#principles
- Dietitians of Canada: Unlock Food.ca. What is a Dietitian? 2018 April. Available from: http://www.unlockfood.ca/en/Articles/Nutrition-Month/What-is-a-Dietitian.aspx
- Adams KM, Lindell KC, Kohlmeier M, Zeisel SH. Status of nutrition education in medical schools. Am J Clin Nutr. 2006 Apr;83(4):941S-944S. Abstract available from: https://www.ncbi.nlm.nih.gov/pubmed/16600952
- University of Oxford. What is a meta-analysis? n.d. Available from: https://www.spi.ox.ac.uk/what-is-a-meta-analysis
- Cochrane Consumer Network. What is a systematic review? n.d. Available from: https://consumers.cochrane.org/what-systematic-review
- PubMed Health. Randomized Controlled Trial (RCT). n.d. Available from: https://www.ncbi.nlm.nih.gov/pubmedhealth/PMHT0025811/
- PubMed Health. Cohort Study. n.d. Available from: https://www.ncbi.nlm.nih.gov/pubmedhealth/PMHT0025833/
- PubMed Health. Case-Control Study. n.d. Available from: https://www.ncbi.nlm.nih.gov/pubmedhealth/PMHT0025837/
- PubMed Health. Cross-Sectional Study. n.d. Available from: https://www.ncbi.nlm.nih.gov/pubmedhealth/PMHT0025838/