New research suggests that people with diabetes who work hard to keep their blood sugar within a narrow range may actually be paying a price when it comes to enjoying daily life. The study, being presented at the Annual Meeting of the European Association for the Study of Diabetes (EASD) in Milan, found that days with slightly more varied blood sugar levels (still within safe limits) were followed by days when people reported feeling better overall.
The findings come from Professor Dominic Ehrmann and colleagues at FIDAM (Research Institute Diabetes Academy Mergentheim) in Bad Mergentheim, Germany.
Why Quality of Life Matters in Diabetes
Living with diabetes means constant attention to blood sugar, food, exercise, and medication. Keeping quality of life high is a key part of good diabetes care, not just staying physically healthy. To understand what really shapes how people feel day to day, the researchers set out to see how blood sugar patterns from continuous glucose monitors (CGMs) affect quality of life in people with type 1 and type 2 diabetes.
How the Study Worked
The PRO-MENTAL study, funded by the German Centre for Diabetes Research (DZD), followed 400 adults with diabetes for 14 days in a row. Most (72%) had type 1 diabetes, and 28% had type 2. Just over half were women, and the average age was 47.
Each day, participants answered five short questions from a well-known wellbeing questionnaire (the WHO-5). The questions asked whether people had felt:
- Cheerful and in good spirits
- Calm and relaxed
- Active and vigorous
- Fresh and rested when waking
- That their day was filled with interesting things
They also rated their sleep, stress, mood, and energy levels each day. Meanwhile, their CGM devices tracked their blood sugar constantly, giving the researchers information on how much time each person spent in the normal range (70–140 mg/dl), below safe range (under 70), above safe range (over 180), and how much their blood sugar fluctuated overall.
The team then looked at whether blood sugar patterns and other factors from one day predicted how someone felt the next day.
The Surprising Finding
As expected, people who spent more time with their blood sugar in the normal range reported better quality of life the following day. Good sleep and higher energy levels the day before also predicted feeling better the next day.
But there was a twist. People whose blood sugar varied a bit more (while still staying safe) also tended to feel better the next day, not worse. In other words, those who kept their blood sugar tightly controlled with less variation actually reported lower quality of life.
What This Might Mean
The researchers think the effort required for very strict control could be part of the problem. Constantly checking numbers, adjusting food, and avoiding activities that might cause blood sugar swings can be exhausting and limiting.
The authors explained: “Days with higher time in the normal safe range for blood sugar were followed by days on which individuals with type 1 and type 2 diabetes reported better quality of life, underscoring the importance of optimal blood sugar control for well-being.”
They added: “Interestingly, higher-than-usual glucose variability was also associated with improved next-day quality of life. These findings may suggest that individuals experience lower quality of life when attempting to minimise glucose fluctuations too strictly, potentially due to the associated burden or restrictions in daily life, which may contribute to some people living with diabetes feeling unable to safely engage in certain activities.”
The Bigger Picture
The takeaway isn’t that people should stop trying to manage their blood sugar carefully. Time in the healthy range clearly matters. But the study is a reminder that chasing “perfect” numbers can come at a cost. Allowing a little more flexibility (as long as they are within safe limits) might make room for things like meals out with friends, spontaneous exercise, or a slice of birthday cake.
For many people with diabetes, that flexibility could make daily life feel more like living, rather than constant managing.