Words Matter - The Nocebo Effect

Updated: Oct 27, 2018

Whether you are a coach, clinician, parent, friend or human your words matter and have an impact on those around you and your own mindset.

If you have more letters after your name it’s likely that other humans trust your words more.

A study on patients with lower back pain showed: ‘Although participants searched the Internet and looked to family and friends [for advice], health care professionals had the strongest influence upon their attitudes and beliefs…such information and advice could continue to influence the beliefs of patients for many years. (1)

I think this extends to anyone in a profession where they intend to help others, myself included. It’s important that we really consider our language when interacting with clients. If they trust us, these words are going to stick around for a really long time in their heads.

I don’t claim to be highly educated or all-knowing, but my clients hire me because they trust my opinion. In the short time that I’ve been coaching I’ve become more aware of the power my words have which in turn has encouraged me to question and rethink my use of language a fair bit.

I’ve put together these lists of words and phrases I hear often that have negative connotations and some alternatives I like to use instead. It’s not an extensive list, and I’m still learning new ways to frame things, but this is what I have so far. Let me know if you have more options worth adding to the list.

One of the most common phrases I hear in my field is simply ‘I’m fat’. It’s not technically accurate to refer to yourself or others as ‘fat’, so why do we do it so often? Is it a helpful statement from a psychological perspective? Probably not.

Every person has body fat, we need some to survive and function optimally. Some people have more body fat that others, for sure, but no person is just purely made up of fat. I prefer to use the phrase ‘I have body fat’ rather than ‘I am fat’.

Another example would be for obesity, an increasing common condition to come across in my field of work.

A person with obesity knows that they have this condition. There is no further need for me as a coach to tell them that they are obese or refer to them as obese.

We wouldn’t refer to someone who has cancer as ‘you are cancer’, so why would we use the phrasing ‘you are obese’? It’s not a helpful phrasing and implies that they are defined by their scale weight or BMI, which they are not. In my opinion using the phrase ‘have obesity’ is more appropriate and less harmful than ‘are obese’.

Obesity is a condition that can be improved with diet and exercise intervention, referring to someone as ‘obese’ negatively implies that they have been, and will always be this way. Not helpful.

These are just some very basic examples but still incredibly powerful ones. Once a mindset shifts from ‘I am fat’ to ‘I have body fat’ steps can begin to be taken to change body composition if this is the goal.

When coaching in the gym I often notice a lot of potentially harmful narratives being thrown around by those who have not considered the power of their words. For example:

‘Don’t arch your back like that when benching, it will give you a bad back’

‘Don’t let your knees go over your toes on the squat, you’ll get knee problems’

‘I don’t teach deadlifts, deadlifting is what caused me to blow my back out and it hasn’t been right since’

‘Your core is weak which is why you have low back pain.’

Not only are all of the above statements false (another post for another time) but the language used is negative, disempowering and leads the person on the receiving end to believe a negative outcome is to be expected if they do any of those things. This encourages fear avoidance around exercises and an association with injury or pain if they do try them.

Another way to describe this would be the ‘nocebo’ effect.

A nocebo is the opposite of a placebo. A placebo influences us to believe in a positive outcome whereas a nocebo influences us to believe in a negative outcome.



a detrimental effect on health produced by psychological or psychosomatic factors such as negative expectations of treatment or prognosis.

Greg Nuckols wrote a great article that touches on the nocebo effect. I’ll insert a paragraph here that really summarises the concept in relation to exercise:

The nocebo effect is sort of like the crappy version of the placebo effect.  With the placebo effect, you expect good things to happen, so good things happen.  With the nocebo effect, you expect bad things to happen, so bad things happen.

recent meta-analysis found that the nocebo effect could have a moderate to large effect on how much pain someone experiences.  Because of this, I’m of the opinion that using fear of injury to get someone to perform an exercise correctly should be your very last resort.  For example, if someones knees are caving in when they squats, instead of saying they’re going to hurt something (ACL, MCL, meniscus, etc.), use performance-based language.  Tell them that if they keep their knees out, they can get their hips more involved in the movement and squat more, or something of that nature.  Now, it may be true that what they’re doing is increasing their risk of injury (tissue damage), but you don’t need to beat them over the head with it, because you could wind up giving them knee pain by influencing their beliefs, even if they never end up experiencing a real injury.  There may be a time and place to eventually say to an especially stubborn individual, “stop doing that exercise that way, or you’re headed for snap city,” but that should be your last resort, not your first.

As Nuckols outlines here I believe what we should be doing when coaching is cueing and explaining what to do during an exercise, not what to avoid doing. This applies to dietary intervention too. Focusing on reinforcing a positive though process and giving encouragement as the client learns rather than highlighting all of the errors they may make and steering the their thoughts back to those in a negative way.

Once you become aware of the nocebo effect, it starts to become noticeable everywhere.

I can think of several occasions where I’ve visited a health professional about an issue and left the interaction feeling downtrodden with a mental list of things to stop doing, a referral to wait on, no actionable advice on what to do to improve the situation and the closing statement ‘you’re just going to have to learn to live with this’.

Being exposed to these sorts of things as a young adult definitely planted fear in my mind which created mental barriers to exercise for me that need never have been there. My personal experiences are not representative of all healthcare providers, I do think there are some great ones out there, just something that I reflect upon. The nocebo effect definitely occurs outside of the fields of medical practice, physiotherapy and coaching.

A quick scroll down the explore page on Instagram and you will find all sorts of nocebo inducing, fear mongering posts around exercise and nutrition. Phrases like ‘Signs of overtraining’, ‘stop doing this stretch’, ‘best carbs for fat loss’, ‘why you have tight hamstrings’ are all examples of how online personalities (with or without credentials) use social media to spread potentially harmful messages without consequence.

These sorts of post are easily identifiable as they are often accompanied by green tick emojis and red X emojis to really hammer the point home that you are doing something wrong and it needs to be fixed.

I’m going to let you in on a secret here. There is no best or worst exercise, there are no good or bad foods, there is no wrong or right form. Sometimes there are more or less helpful or efficient options, but it’s almost always dependent on context, something these posts cannot possibly encapsulate. Don’t let an online ‘guru’ convince you that your spine is out of alignment, it most probably isn’t. Instead, question why these posts are made and perhaps ask their creator why they are nocebo’ing strangers into believing in the worst outcome.

I once saw a post on how to deadlift that had a mushroom cloud placed over someone’s rounded back. An actual mushroom cloud explosion. That nocebo’d me so hard I almost had to wash my eyes after even though I know very well that rounding your back on a lift isn’t inherently dangerous.

(The research on this is all over the place. As far as I know spinal flexion when lifting hasn't been clearly correlated with a higher injury risk. Other factors like load management, stress and just plain old luck are more closely linked with injury rates in lifting athletes. Sure, it’s not always the most mechanically efficient way to pull but you can get wicked big erectors pulling like that. Some coaches even program weighted spinal flexion exercises, there really are no good or bad exercises. World record 1RM deadlifts are almost always done with a flexed spine, doesn't that make a good case for cat back deadlifts being the most optimal for force output? There's much to ponder here. For more reading on this stuff check out articles 3 and 4).

Getting back to the point there’s almost always a motive here with these posts, perhaps the page sells a really convenient ebook full of stretches for your ‘tight hips’ or a magic tea that can ‘heal your leaky gut’. It's gonna be a no from me mate.

Be very wary of anyone that talks in absolutes like ‘best’ or ‘worst’.

It’s also possible to nocebo yourself via the language your internal monologue uses. We all talk to ourselves (yes, it's okay to admit that), we should be carrying over our use of appropriate language to ourselves.

For example: If you saw someone doing front squats in the gym and thought to yourself ‘I want to try that, but I don’t have the mobility for it so I’ll probably get hurt’ you just nocebo’d yourself. If you go in with that mindset you will likely hyper-analyse every uncomfortable sensation and be more likely to report a tweak or injury right off the bat.

Instead focus on shifting that mental dialogue to ‘I want to try that, but I’ll need to learn the technique and work on my mobility a little’ and then get at it.

Most of the time we can overcome these mental barriers just by recognising a disempowering thought and then thinking more proactively. I don’t mean to get gooey here and gush about positive thinking, because that’s not what I believe this is.

It’s critical thinking. It’s being responsible with your words and thoughts. It’s developing a mindset for growth and improvement.

Loosely I’ll reel that back in to: Just be a better human.

Cheesy quote:

“Do the best you can until you know better. Then when you know better, do better.” —Maya Angelou.

Key takeaways:

  • If you are in a position of power or trust, don’t plant seeds of worry in other people's heads via the language you use.

  • Focus on what you/ your client can do to improve an outcome, what you/ they are currently doing that’s helpful to their goals and reinforce actions these with positive language.

  • It’s not okay to nocebo your clients, yourself or people you don’t know on social media.

I also jotted down a list of terms and phrases I personally do not use with clients and don’t believe are appropriate or helpful in the majority of situations. You don’t have to agree with all of them and some of them may not apply to you, but I think they are worth reviewing.


(1) The Enduring Impact of What Clinicians Say to People With Low Back Pain

(2) Good stuff from Nuckols:

(3) Spinal flexion

(4) More on flexion