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Author: Alice Henneman, MS, RDN
- “Lose 10 pounds overnight!”
- “Avoid eating (name of food) to prevent dementia, autism, etc.!”
- “Eat (name of food) to burn fat!”
Promises, promises — the Internet is full of claims about special powers or pitfalls from eating various foods.
Following a false dietary claim that is ultimately ineffective may deprive you of foods you enjoy or contribute to needless expenses for special foods, supplements, etc. On a more serious note, you may delay getting needed treatment for a medical condition with resulting additional expenses and/or health consequences.
In searching for information on the Internet, the most sensational information may come up first as that is what tends to get read. You’re not likely to find a lot of peer-reviewed journal articles coming up at the top of a search.
How do you separate fact from fancy? Here are some guidelines to get you started.
The Claim is Too Good (or Too Horrible) to be True
Weight loss plans frequently fall in this category. Rapid weight loss is promoted. Food choices are limited or the plan warns one or more foods will make you ill.
Legitimate diet plans recommend slow steady weight loss of about 1–2 pounds a week with a food pattern based on eating balanced, nutritious, wholesome meals. Most fad diets will work in the short term because they cut calories. However, they fail in the long term because they may be expensive, become boring, don’t fit into a normal lifestyle and/or don’t teach you how to lose weight for a lifetime. The Cabbage Soup Diet and the Grapefruit Diet are examples of diets that have come and gone.
Correlation Does Not Equal Causation
A relationship may be implied between two variables because as one circumstance increases, the other also increases (or decreases) proportionally. However, that doesn’t mean one caused the other. For example, at one time some “experts” felt eating ice cream caused polio. Both ice cream consumption and polio peaked in the summer months. While there was a “correlation” between these two events, it was not a “causation.” Ice cream did not cause polio in children. The actual cause was polio is a type of virus that is more likely to cause disease in the summer.
Read carefully to learn if further research was done on additional possible causes. If there might be several possible causes, was the testing sufficient to single out one cause?
No Formal Testing Was Done to Validate a Claim
Are the recommendations based on testimonials, personal experiences or observations? When possible, scientists compare results from subjects given a certain treatment or substance to a “control group” not given the substance being tested. Both groups are allocated randomly. Additionally, the subjects don’t know which substance they’re receiving.
People will often say they feel better after trying a certain diet, product or treatment because they perceive it will make them feel better — it’s called the “placebo effect.” In a “double-blind” study, the researchers also don’t know which treatment a group receives until the results are in.
Before an article can be published in a creditable scientific journal, it must be peer-reviewed as to the quality of its information and the methods used to obtain the results. As for Internet articles, anyone can publish information on the Intern
The Author is Selling Something
As part of the author’s recommendations, he or she may try to sell a product, supplement, plan or service. Be especially wary if you’re offered a diagnosis of your health status and then told a product sold by the author will help you.
The Author Has Little to No Specialized Training in Nutrition
What are the author’s credentials? If he or she has an advanced degree, what type is it? Is it from a recognized college or university? How was it obtained?
There are several examples of animals whose owners obtained PhD’s for them through diploma mills. One of the most famous animals with a doctorate degree was “Dr. Zoe D. Katze,” a housecat.
If the person has an authentic degree, do they practice within the realm of generally accepted science? Or, do they operate on the fringe with little to no actual research to support their claims?
Check the “about us” page or mission statement to see if they have an editorial board. Are these people with recognized credentials?
Supporting Information for the Food Claim is “Cherry-Picked”
Only positive studies are cited to support the food claim or negative studies as to why you shouldn’t eat a specific food.
Information is Based on Just One Study or a Limited Number of Studies
If promising results are obtained from a study, scientists will follow up with more research to gather additional information and determine if the results of the first study can be replicated. Scientists also will examine whether there may be any harmful side effects.
Look for dates on cited studies. Science is constantly evolving — recommendations based on old studies may no longer provide the latest information. If there are many broken links on a site, it may not be kept up to date.
Consider the Source
Iowa State University Extension and Outreach advises checking the web address.
- Those with .gov are funded by a government agency, such as www.cdc.gov.
- An educational institution is indicated by .edu such as www.extension.unl.edu.
- Professional organizations, such as scientific or research societies, are indicated by .org such as www.heart.org.
- Commercial sites use .com and may be funded by a company. They commonly promote and/or sell a product. Follow the guidelines in this article to evaluate the quality of their information.
Still confused? Get a second opinion from a recognized nutrition professional. Colorado State University Extension gives these recommendations:
- Receive a referral from a personal doctor or local hospital.
- Check with the Academy of Nutrition and Dietetics (AND) website to find a referral for a dietitian in your area: www.eatright.org.
- Contact your local public health department, Extension Service or nutrition department of a state or local university.
- Bellows, L. and Moore, R., Nutrition Misinformation: How to Identify Fraud and Misleading Claims. Sept. 2013. Available at www.ext.colostate.edu/pubs/foodnut/09350.html last accessed July 23, 2015.
- Caselli-Mechael, L., 12 Steps for Spotting Bad Science. September 16, 2014. Updated January 14, 2015. Available at www.foodinsight.org/12StepsForSpottingBadScience last accessed July 23, 2015.
- Eichel, S.K.D., Credentialing: It May Not Be the Cat’s Meow. 2002. Revised 2011. Available at www.dreichel.com/articles/dr_zoe.htm last accessed July 23, 2015.
- National Institutes of Health (NIH). MedlinePlus. Medline Plus Guide to Healthy Web Surfing. Available at www.nlm.nih.gov/medlineplus/healthywebsurfing.html last accessed July 23, 2015.
- Shafer, E. and Miller, A. 2007. Revised 2013 by Gatewood, J. and Litchfield, R. Survivor’s Guide to Healthy Web Surfing and Phone Apps. Available at www.extension.iastate.edu/Publications/N3418.pdf last accessed July 23, 2015.