I’ve never really been a supplement person. I know many people are, religiously taking their multivitamins every day, maybe their vitamin C or iron – my mum has an array of supplements she takes every morning without fail.
I guess I’m a big believer that having a healthy diet should be enough to get everything that your body needs. That, and the fact that no one needs 200% of their recommended RDA on top of their diet every day. And the fact that there have been numerous articles detailing why most supplements are pointless (eg here, here, here, here, here).
So when my annual blood test (yes, I come from a family that passionately believes in annual check-ups) revealed a vitamin D deficiency, I reluctantly purchased a bottle of vitamin D pills (alongside some probiotics, because why not?). After all, you can’t really get vitamin D from food, and due to my melanoma history, I have to be very careful in the sun.
I am the nightmare patient all health behaviour experts dread
That same bottle of pills is still in my cupboard. It’s been there for at least a year (possibly even more). For a while, it lived on the kitchen counter, as I tried to make it more salient and remind myself to take it. I tried to create a habit and always take it at lunch so that as soon as I have lunch I would be primed to take it.
None of it worked. Why?
Although changing the environment to make habit formation easier is a key part of behavior change (especially behavioral design and behavioral economics), there was clearly something missing here – belief.
- I have already said that I am not a big believer in supplements. When people tell me about the supplements they take I ask them why, and when people ask me whether to take supplements I usually suggest that they check their diet first.
- I wasn’t really feeling unwell in any way, and my levels were low but likely comparable to the rest of the country given the lack of sunlight.
- I didn’t really see much benefit in taking it
Unless you create really clever ways to change the environment that bypass these issues, belief is a big barrier. Belief changes everything. And belief means that the bottle of vitamin D is still in my cupboard, half-full. After all, it’s so much easier to keep doing what you were doing before than to change your behavior.
Fast forward a year later
My annual blood test, again. Vitamin D levels, low again. But this time, something was different. My vitamin B12 levels were dangerously low. They were in the red zone. They were so low, the doctor left a note saying they recommended urgently going to see my GP to discuss B12 injections. That I could be suffering from an autoimmune disease called pernicious anemia, which means not being able to absorb B12.
Obviously, here the tone was slightly different. And so was the outcome.
Here comes my behavioural science lesson
I bought my B12 supplements and have been taking them every day without fail for the past 2 months.
I created a habit
As with the vitamin D bottle, I tried to prime myself and create a habit. I placed the bottle of pills on the kitchen counter and aimed to form a habit of taking them every day after lunch.
I had a clear goal
I decided there was a need for an experiment. I could have gone to the doctor straight away, but instead, ever the scientist, I wanted to see if indeed I was suffering from pernicious anemia or whether I wasn’t actually eating enough B12-rich food (which a daily supplement would solve with no problem).
So I decided to take a supplement every day for 2 months and then have another blood test to see if my levels were better. My goal was to understand what was actually going on so I could take appropriate action. That meant taking the supplement every day, otherwise, the experiment would be void.
I was shit-scared of what might happen if I don’t take them
Crucially, in this case, there was belief. A lot of it. The situation was dire. The levels were red. The doctor urged immediate action.
I was scared into taking action.
I believed that if I didn’t take action, there would be consequences – bad things would happen. I believed that taking action was important for my health.
So do we need to scare people to change behaviour?
Hopefully, that’s not the message I leave you with. What my experience reinforced to me first-hand is that without understanding why someone doesn’t take their medication (or whatever behavior we are interested in) we can’t really design interventions that change behavior. If they do, it’s probably more luck than anything else.
We also can’t make sweeping generalizations about what all people are like. Different things work for different people because we are all individuals with distinct experiences, beliefs, and environments. What worked for me may not work for you.
And in case you’re wondering
My experiment worked. My vitamin B12 levels are now back to normal. My behavior change has been reinforced by the results of the blood test, so I continue to take my supplement every day.
