There’s a sentence I hear so often I can now see it coming: “My GP says everything’s normal, so why do I feel like this?”.
This week’s episode was our first listener Q&A of this series, and that frustration ran underneath half the questions. The podcast is the short version. This is the longer one for anyone who wants to know why “normal” and “well” can genuinely come apart, and what the research actually says about it.
Start with what a blood sugar result is. An HbA1c is an average: roughly, where your blood sugar has sat over the previous few months, condensed into one figure. And an average, by design, throws away the shape of the thing it’s summarising. Two people can share a number while living completely different days: one steady from morning to night, the other spiking and crashing their way through, the highs and lows cancelling out neatly on paper.
For a long time that was just a reasonable suspicion. Then continuous glucose monitors let researchers watch the pattern directly. In one Stanford study, Hall and colleagues put monitors on 57 adults who had no diabetes diagnosis (most would have been told they were fine) and found that many of them were spiking into the impaired-glucose, and in some cases the diabetic, range, entirely unseen by standard single-point and average measures (Hall et al., 2018).
Their point was blunt:
the usual tests lean on averages and single moments, and in doing so they neglect the dynamics. The day has a shape, and the shape was being missed.
That is the science underneath “I feel rubbish but I’m told I’m fine”. If your blood sugar is lurching rather than gliding, you can feel every lurch (the afternoon flatness, the sudden hunger, the wired-but-tired evenings) while the average all that lurching produces still lands somewhere unremarkable. You’re not imagining the day. The test just isn’t built to show its shape.
“Normal” is not always a safe place to be
Now the second half, because there’s a related myth worth dismantling: the idea that “normal” is a flat, safe plateau, and that things only go wrong once you cross a line. It doesn’t work like that. In the ARIC study with more than 11,000 adults with no diabetes at the outset, Selvin and colleagues found that the risk of later developing diabetes, and of cardiovascular disease, climbed step by step as HbA1c rose, including across the bands we’d currently label normal or borderline (Selvin et al., 2010). Risk didn’t switch on at the threshold. It rose gradually, along the whole range.
Two things follow, and they’re why I keep going on about direction. First, a “normal” number sitting at the top of normal is not the same as one sitting comfortably low. The research treats risk as a slope, not a cliff edge. Second, the most useful thing about your result usually isn’t today’s figure at all; it’s the line it’s been drawing over the last few years. A number that has crept from low, to middling, to the top of normal across three annual checks is telling you something a one-off “you’re fine” simply can’t. The dot reassures. The trend is the actual conversation.
Selvin et al., 2010
I want to be honest about the limits too, because a deep dive that only tells you the alarming half isn’t worth your time. We don’t yet fully know how much those glucose spikes matter over the long run for someone who is otherwise healthy, as it’s an active area of research, not a settled verdict. One number is not a destiny. And all of this is population-level: it describes patterns across thousands of people, not a prediction about you specifically. What it does do is give you permission to take your own experience seriously, and to treat the afternoon crash, the broken sleep, the cravings that arrive on cue as information.
So if you’ve been told you’re fine and you don’t feel fine, here’s the reframe I’d offer. “Fine” is a line drawn across a continuum, using a test that reports the average and quietly discards the shape. Both things can be true at once: your number can sit inside the normal range, and your body can be telling you something real. A good option is to look at the direction, not just the dot, and to stop treating how you feel as though it doesn’t count as evidence.
If you’d like to spot the pattern in your own week, my free guide Is Your Blood Sugar Working Against You? Ten Signs Most People Completely Miss is the quickest way. And if you’d like to talk your own picture through properly, my free 30-minute Blood Sugar Audits are currently open; if you’re thinking further ahead, you can book a discovery call too.
Thank you for being here.
See you next week,
Frances x
Frances Norgate
Qualified Nutrition and Lifestyle Advisor
