What Your Blood Sugar Is Actually Telling You — and How to Listen
Managing diabetes doesn't require a medical degree, but it does require understanding a few key ideas that clinics often don't have time to explain properly.
Blood sugar. Glucose. HbA1c. Glycaemic index. If you have been diagnosed with type 2 diabetes or told you are at risk, you have probably heard all of these terms — sometimes in the same appointment, with a waiting room full of people outside the door. It can feel like information arriving faster than you can absorb it. This guide is an attempt to slow that down and explain, in plain language, what your blood sugar is actually doing throughout the day and what you can reasonably do about it.
Your blood glucose level is simply the concentration of sugar in your bloodstream at any given moment. After you eat, particularly after carbohydrate-rich food, your blood sugar rises. Your pancreas responds by releasing insulin, a hormone that helps your cells absorb that glucose for energy. In type 2 diabetes, this process becomes less efficient — either the pancreas produces less insulin than needed, or the body's cells have become less responsive to it, a condition called insulin resistance. The result is that glucose stays in the bloodstream for longer and at higher concentrations than is healthy.
HbA1c is the measure your GP uses to track how your blood sugar has been behaving over approximately three months. It works by measuring how much glucose has attached itself to your red blood cells — a process called glycation. A high HbA1c suggests blood sugar has been consistently elevated. The target for most people with type 2 diabetes is below 48 mmol/mol, though your GP may set a personalised target based on your age and other health factors. It is worth asking what your number actually is, not just whether it is "okay".
Key number to know
The target HbA1c for most people with type 2 diabetes is below 48 mmol/mol. Ask your GP or practice nurse what your current reading is at your next appointment — and what the trend has been over the last year. Numbers in context are always more useful than a single result.
The glycaemic index, or GI, is a ranking of how quickly different carbohydrate-containing foods raise blood sugar. White bread and sugary drinks sit at the high end — they spike glucose rapidly. Lentils, oats, and most vegetables sit at the low end — they release glucose slowly and steadily. In practice, the GI of a meal depends on many factors: what else you eat at the same time, how the food was cooked, even how ripe a piece of fruit is. A useful rule of thumb is to pair carbohydrates with protein, fat, or fibre, which slows the whole meal's glucose release.
Physical movement is one of the most powerful tools available for managing blood sugar, and it works in a way that is often underexplained. When your muscles contract during exercise, they absorb glucose from your bloodstream directly — without needing insulin to do it. Even a ten-minute walk after a meal can meaningfully reduce a post-meal blood sugar spike. You do not need a gym membership or a structured fitness plan to benefit; what matters is regular, gentle movement woven into daily life.
Sleep and stress are less discussed but genuinely significant. Poor sleep raises cortisol, a hormone that pushes blood sugar up. Chronic stress has a similar effect. This does not mean that managing diabetes is about achieving perfect calm — stress is a normal part of life. But it does mean that strategies for sleep and stress management are a legitimate and important part of diabetes care, not an optional extra.
At Vibrant Health Advocates – Lyra, we discuss all of this in our workshops — not as a lecture, but as a conversation among people navigating the same challenges. Understanding what is happening in your body does not remove the difficulty of managing a long-term condition, but it can replace fear with agency. And agency, it turns out, makes an enormous practical difference.