The 5 Whys of carb counting

Raj Patel
Raj Patel

Answering a question as straightforward as ‘Why do people with diabetes carb count?’ is incredibly difficult for people without the experience of living with diabetes.

At Quin, only one of us is living with diabetes. We therefore need ways to discover what people with diabetes truly need if we are to design an experience which can give people more confidence and make living with diabetes easier. 

One of the best techniques we use as part of our research programme is the 5 Whys.

carb counting

The 5 Whys is a technique to uncover the root cause of a problem. Your car doesn’t start because the battery is flat but the root cause is that you left the headlights on last night when you came home. 

As product designers, we have repurposed the 5 Whys as a discovery tool for uncovering people’s needs beyond the obvious wants and asks. 

It mirrors how we learn as young children – we keep asking why. As any parent or teacher may know, young children don’t stop asking why. We just run out of answers which make sense to respond with. Asking why becomes very useful and less annoying in the workplace.

The first couple of why questions we ask uncover only the most basic responses. Few surprises are discovered here. By the fourth and fifth questions, a depth of true need starts to be found which can have a profound impact on the product experience.

For this blog, we will frame around a simple question fragment: ‘Why do people with diabetes want…’ 

If you are living with diabetes or know someone with diabetes, try answering the questions yourself below to see if you agree or disagree with what we’ve learnt. 



1. Why do people with diabetes want to carb count?


The first and most obvious response is people with diabetes don’t want to carb count. They have to carb count. 

This isn’t just semantics. This is an important point. Every day, people with diabetes are performing extra tasks they don’t want to be doing. 

diabetes cookies

Designing an app around a feature people don’t want to be doing may provide benefit on a basic, functional need but the overall improvement to quality of life hasn’t really changed. If anything, it may trigger more mental anxiety spending time and focus on a task they don’t want to be doing.

After acknowledging the initial response, we try to answer the first why and we get a basic answer:

To know how many carbs they are eating. 

Which takes us onto the second why:


2. Why do people with diabetes want to know how many carbs they are eating?


Again, very little difference between responses here: 

To know how much insulin to dose.

Whether it’s from your healthcare professional, programmes like DAFNE, or online peer-support, carb counting and the associated carb ratios are an elementary way to provide a baseline level of confidence when injecting short- or rapid-acting insulin. 

We know they regularly do not produce the outcomes expected and lead to much self-examination and criticism, but in the absence of a better system, they do a very good job of keeping people with diabetes alive.


3. Why do people with diabetes want to know how much insulin to dose?


This seems like a straightforward question to answer but we start to see a few different, though similar, responses at this stage. 

For some, this is to avoid the extremes in blood sugar levels. Insulin can have a drastic effect on blood sugar so determining an appropriate amount of insulin for each food situation is crucial. Take too much and the risk of hypoglycaemia is increased. Take too little over a period and hyperglycaemia is a distinct possibility.


For others, the aim is to stay in range. This builds upon avoiding the extremes with a longer term and more constant need. For each person, ‘in range’ may have a different definition and this is perfectly okay. 

Knowing how different people approach their dosing of insulin helps us develop an inclusive experience. We can’t always solve challenges for everybody at once – we are still a small startup – but the discussions we have enable us to carefully consider the design to support many needs with a single experience.

So we’ll summarise the answer as:

To know their blood sugar is in the ideal range.


4. Why do people with diabetes want to know their blood sugar is in the ideal range?


Now we’re starting to peel away the basic layers. Most apps stop here. We’ve got the basic understanding around the actions that people take but we’re still far from being human-centric. 

Instinctively, people seem to respond to this question with fears: to avoid feeling unwell in the short term due to being too low or high; to not require immediate medical intervention; to prevent the longer term adverse effects and complications associated with high blood sugar. 

We don’t want to feed the fears in an app. Reminding people constantly of the potential dangers they face is both anxiety and depression inducing, regardless of how friendly you make the messages. 

We acknowledge the presence of these fears and look at the summarised, positive spin within the responses:

To know they will be healthy.

Do existing diabetes apps provide an experience that let you know you will be healthy in the future or assist with the decision making to help you stay healthy? 

Do they use information that you may be unhealthy to scare you into action with little support on how to change the outcome? 

Does all this responsibility still lie with you to work out after closing the app?


5. Why do people with diabetes want to know they will be healthy?


The fifth and final why. Responses to this level of questioning start to expose a deeper and wider scope of human needs. 

We have answers which can involve mental health such as not living a life in a state of fear or anxiety. 

We see the desire to stay in control both mentally and physically of your life, having a say in how your life proceeds. 

living with diabetes while black

We find that external factors of life are ultimately those which are most important: quality time with friends and family; the ability to focus on work life and the rewards that brings; daily activities which aren’t impacted by the worry of them being interrupted.

We can understand that people really just want: 

To be safe to live their lives how they want to live them.

The goal of every product experience in diabetes tech and healthcare should be to remove the barriers which prevent people living the lives they want to live. Anything less and we’re adding to the heavy strains of living with diabetes. 


Truly human-centred


It’s essential the experience we design supports all layers of needs that we have uncovered. 

Most diabetes apps will only ever focus on the top three layers, building features around the real basics wants and needs. Consequently, these apps haven’t been embraced as widely as they could have within the diabetes community. There is a reason companies advertise their ‘registered users’ and not ‘active users’.

At Quin, we ensure that when we’re designing our app we consider all these responses and more across many questions we ask ourselves and the people with diabetes who have contributed to our research programme. 

We know we aren’t yet in a position to fully solve all the challenges but we are a lot further forward with our thinking than many other companies.

By the end of 2020, we believe we will have an experience that is truly unique in the world of digital diabetes. If you want to see how we have used the 5 Whys to rethink food recording and carb counting, look out for our new food flow coming in August. 


What were your answers to the 5 whys?


We don’t ever presume to know it all. We’d love to hear your answers and thoughts – if you agree or disagree, if you learned anything or thought this was all obvious. Join the conversation and share your thoughts with us and other people with diabetes on Instagram and Twitter. 

If you would like to see the output of our human-centred design thinking, download the Quin app from the Apple App Store.


Enjoyed this post? Click here to read about 3 Reasons to Start using Quin now or

check out Barry’s previous post on What is a Diabetes Decision? 

Raj Patel
Raj Patel