We are the parents of a French 10 year old girl, diagnosed with type 1 diabetes a year ago. After the first shock, we learned a lot about how to adapt insulin to life and not life to insulin. We wanted to avoid the meal-planning method that involves keeping the total carbohydrate intake at each meal consistent from day to day. This really helped our daughter to accept her illness.

It took a couple days to discover that carb counting would be our best friend. We started counting everything using labels and a scale in the kitchen. We discovered all the ratios for insulin bolus and corrections, which allowed a good blood glucose control, with the help of our doctor. We also learned how to use glycemic index of food to better anticipate increases in blood sugar and tried to take into account stress and physical activity. The burden of insulin treatment was our daughter’s, but the burden of accurate carb estimation became ours… until she can bear both of them on her own.

Her first HbA1c was so good (6.4) that we knew we had found the main key for a treatment as serene as possible. But there is something we don’t understand: why do most people with type 1 diabetes around us put so little energy into carb counting? Why do they use gross approaches like “portion to insulin” or “the exchange system”, which require a lot of knowledge and constraints? We are even told that trying to be accurate in carb counting is too much pressure for our girl, and that it is better to do it just by glance estimation. But to abandon accurate estimations for gross estimations seems a huge mistake to us, because meals are immediately followed by high and lows when we do so. Why does nobody encourage us toward accuracy?

We decided to go a little beyond our first circle of friends and doctors and launched a survey on twitter, in partnership with diabetesNews, to understand a little better T1D people’s habits in regards to carbs counting. Here are the key findings we are glad to share with all. See also the short infographics: Click here to see the infographic

1. We are not alone, not at all: 91% of our 160 respondents practice carb counting at each meal! Actually, a lot less in France where only 75.

2. But despite their daily efforts (effort is an euphemism), it is sad to see that only 11% of them have an accurate glance estimation of the test meal snapshot we showed in the survey. T1D people fear hypoglycemia. Therefore, they tend to underestimate carbs: 74% of them are under the target by 15% or more. Studies say that a 10% error does not affect blood glucose balance too much, but 62% of respondents were between 25% and 55% underneath or above the target.

3. More experienced people were more accurate, almost 1 out of 2 had a good answer with less than a 15% error margin.

4. The survey seems to show that those who frequently use apps or booklets, are a little more accurate in this glance exercise. It is true that they are very good pedagogical tools!

We cannot be satisfied with these figures, considering, if these results are true, that 8 million people with T1D in Europe and North America, count carbs three times a day with this error rate. This survey shows that human glance estimations cannot be accurate enough, especially for beginners like us, but also for 1 out of 2 experienced people. We all know the immediate or long term complications of bad blood glucose control. Therefore, we will stick using food labels, our portable scale, and our calculator, as long as necessary, even if it is sometimes cumbersome. Our daughter deserves it!

About the authors: Remy and Astrid live in Paris with their three children. When their 10 years old daughter was diagnosed with type 1 diabetes in 2013, they found help with the French youth diabetes association (AJD). They are both consultants in HR and management.