In this age of information it can be difficult to determine which piece of nutrition advice you hear is true. You don’t want to waste your time or money on ineffective treatments. Here are a few simple questions you can ask yourself to help figure out whether or not you should follow any particular piece of nutrition advice you encounter:
How sensational is the advice itself?
You can glean a lot about nutrition advice in the way it’s communicated. Good advice tends to be measured. It often contains statements that are qualified and is probably something that, at least in some way, you’ve heard before. Conversely, if something is made to sound revolutionary, that’s usually a good indicator it’s anything but. When you hear terms like “miracle cure”, “superfood” and “all natural” being thrown around alarm bells should start going off inside your head. This usually means the product, diet or practice being advocated for is based less on science and more on selling false promises.
What is the evidence?
If the advice sounds reasonable to you, the next thing you should look into is the evidence behind it. Any advice worth following should be able to cite references from which its conclusions are drawn. Ideally this evidence should be in the form of studies from peer-reviewed scientific journals. Be aware that not all evidence found in scientific journals is equal. Below is a nice illustration ranking the caliber of scientific evidence.
As you can see the best forms of evidence are systematic reviews and randomized controlled trials. Systematic reviews are compilations of many individual studies Since they are an aggregate, outliers (ie. results that conflict with the majority) are weeded out. Randomized controlled trials are also great because their design works to eliminate a researcher’s and study participant’s biases. If you’re not lucky enough to have scientific references it doesn’t guarantee that the advice is bogus, but you’re certainly behind the eight-ball.
What many people selling unproven health advice tend to rely on is anecdotal evidence. Anecdotes are basically stories about how the advice worked for other people. Setting aside the possibility that the advice being prescribed isn’t an outright lie (which undoubtedly occurs), there are other reasons why you shouldn’t take anecdotes as fact.
The first is that they don’t have controls. What do I mean by “controls”? Controls isolate the treatment and allow researchers to determine whether or not it was the treatment that caused the effect. For example, if someone tells you that eating blueberries (ie. the treatment) has improved their energy levels. It may be true that this person’s energy levels have improved but how do you know that this is a direct result from eating blueberries? There could be a million reasons why that person’s energy levels increased and without controls it’s impossible to attribute this to eating blueberries.
A second reason to be skeptical of anecdotal evidence is the placebo effect. The placebo effect is a phenomenon that occurs where a placebo, or a fake treatment, has the ability to improve a patient’s condition, for no other reason than the patient believes it will be helpful. Researchers don’t fully understand why this occurs, but it’s clear that it does. Homeopathy is a great example of this. Subscribers to homeopathy swear by its effectiveness. While it’s entirely possible that people using homeopathic treatments see improvements in some conditions, repeated studies have shown that homeopathy does NOT offer benefits greater than placebo alone. In other words any benefits people experience undergoing homeopathy are not due to the homeopathy itself, but rather due to the placebo effect.
Where is the advice coming from?
The next thing you’ll want to consider is who is giving the nutrition advice. Does the person have any credentials? It’s a good idea to look for advice that is prescribed by medical doctors (MDs), dietitians (RDs or RDNs), academic researchers or journalists from reputable publications. These qualifications indicate that the people giving advice have received scientific training that allows them to properly evaluate the evidence for the advice they’re prescribing. Naturopaths and other alternative practitioners generally haven’t received comprehensive scientific training and thus it’s a good idea to take their claims with a heavy dose of skepticism. The same goes for celebrities and other media personalities.
Are there any conflicts of interest?
A conflict of interest is defined as a situation in which a person or organization is involved in multiple interests (financial, emotional, or otherwise), one of which could possibly corrupt the motivation of the individual or organization. Unfortunately, this sort of thing happens all the time in the area of health and nutrition, most often in the form of the selling books or supplements. It’s a huge red flag if the person telling you that you need to go on a particular diet or take this new miracle cure also stands to gain financially if you do so.
Another common conflict of interest could be the funding source for a research study. Is the study funded by a company or industry who stands to benefit from the results? If so, it’s a good idea to take that advice with a grain of salt.
Be skeptical. If there’s one thing you should take away from this article it’s that.
For better or for worse, good science moves slowly and incrementally and people claiming otherwise usually have a stake in you believing as much. Never forget – advice that sounds too good to be true, almost always is.