Blood sugar in men: values, symptoms and what your blood shows

Your blood sugar is one of the most underrated numbers on your blood test. Yet it gives you one of the earliest signals when your metabolism starts to struggle, often years before you notice anything. Around 1 in 10 people in the Netherlands live with diabetes, and in men the problem tends to start at a younger age than in women.

Let's be honest: most men only think about their blood sugar when the GP brings it up. That's a shame, because blood sugar is exactly the kind of value you can track early and that says a lot about your direction. This piece covers which values exist, what counts as normal, and why it plays out a bit differently for you as a man.

What are blood sugar values, exactly?

Your blood sugar, or blood glucose, is the amount of sugar circulating in your blood at a given moment. That sugar is your main fast fuel. Your body tries to keep the number within a narrow range using insulin, the hormone that moves sugar out of your blood and into your cells.

Eat something with carbohydrates and your blood sugar rises, so your pancreas releases insulin to bring it back down. When that system runs smoothly, your blood sugar stays stable. When it slowly falters, the sugar stays too high, and that is exactly what shows up on a blood test.

One thing to grasp: a single reading is a snapshot. That's why several ways to look at your blood sugar exist, from a fasting sample to a value that captures your average over months.

Which blood values say something about your blood sugar?

A few core values together paint a picture of your sugar balance. Each looks from a different angle: the moment, the average over months, and how hard your pancreas has to work. Together they tell you more than any single value.

The first value you often see is your fasting glucose. If you want to know how to read that result, see our piece on fasting glucose in men.

The long-term value is your HbA1c. It catches the trend, not last night's random spike. What it means is covered in our piece on the HbA1c value.

What is a normal blood sugar value?

In healthy people, fasting blood sugar usually sits between roughly 4.0 and 6.0 mmol/l. Values between 6.1 and 6.9 mmol/l may point to a disturbed sugar balance, often called prediabetes. From 7.0 mmol/l fasting onwards, doctors generally speak of diabetes, though only a doctor confirms that.

According to the Diabetes Fonds, these are guide values, not absolute borders. Your value can swing with sleep, stress, illness or a heavy night before. One raised reading doesn't make you ill, but it is a reason to look again.

Your HbA1c uses different numbers, in mmol/mol. Under 39 mmol/mol is often seen as normal, 39 to 47 as the prediabetes range, and 48 or higher fits the diabetes criterion. That too is a rough grouping, not a diagnosis on its own.

Why blood sugar plays out differently in men

Men tend to develop type 2 diabetes at a lower BMI than women. That's because men store fat around the belly and organs sooner, and it is exactly that belly fat that disrupts your sugar balance more than fat on your hips or legs.

That explains why a man who doesn't look heavy but carries a beer belly can still have a raised blood sugar. The scale doesn't tell the whole story; your waist often says more. A waist above 102 centimetres counts as a clear point of attention in men.

There's something else women don't have: the interplay between your blood sugar and your testosterone. Those two sit closer together than most men think, and that makes blood sugar a doubly interesting number for you.

Blood sugar, belly fat and testosterone

There's an awkward loop between belly fat, insulin and testosterone. Belly fat makes you more prone to insulin resistance, insulin resistance links to lower testosterone, and lower testosterone in turn makes it easier to lay down more belly fat.

That isn't a reason for doom, because it also works the other way. Losing weight around your waist can nudge both your sugar balance and your hormones in the right direction. How that triangle works is covered in our piece on belly fat and the testosterone-insulin connection.

For you as a man, this means your blood sugar isn't separate from your energy, your libido and your shape. It is one of the knobs that several things hang on at once.

From prediabetes to type 2 diabetes

Prediabetes is the grey zone between normal and diabetes. Your blood sugar is higher than healthy, but not high enough for a diabetes diagnosis. The tricky part is that you usually feel nothing, while the basis for problems is already being laid.

The key message: prediabetes is often reversible. In the well-known Diabetes Prevention Program study, a lifestyle approach lowered the risk of type 2 diabetes by 58 percent, more than medication in the same study (Knowler, NEJM 2002). That is exactly the phase where you still have a lot of influence.

Signals you sometimes do notice include more thirst, urinating more often, fatigue or slower recovery. If that sounds familiar, read our piece on recognising insulin resistance, since that is often the engine under a rising blood sugar.

Metabolic syndrome: when the risks come together

A high blood sugar rarely travels alone. It often comes with a larger waist, high blood pressure, high triglycerides and an unfavourable cholesterol. When a few of those coincide, doctors speak of metabolic syndrome.

That cluster matters more than any single value, because the risks reinforce each other. Your triglycerides and cholesterol belong to the picture just as much as your glucose. How those five factors connect is covered in our piece on metabolic syndrome in men.

The flip side is encouraging: the same steps that improve your blood sugar often tackle several factors at once. One approach, several wins.

Which symptoms does a high blood sugar cause in men?

The tricky thing about a high blood sugar is that you notice nothing for a long time. Only when the values climb sharply do complaints appear. And men in particular often attribute those complaints to being busy, age or a bad week, while something else is going on.

Signals that may point to a raised blood sugar include more thirst, urinating more often, fatigue, blurred vision and cuts that heal slowly. Less interest in sex or less reliable erections sometimes belong to the picture too. None of these complaints proves anything on its own.

If you recognise a few of these at once, that's no reason for panic but it is a reason to have your blood sugar looked at. The good part is that in this stage you often still have a lot of influence.

Blood sugar and your heart

A long-term high blood sugar eventually damages your blood vessels, and that affects your heart just as much as the rest of your body. That's why diabetes often comes with a raised risk of cardiovascular disease, especially if your blood pressure and cholesterol are also unfavourable.

For men, that's another reason not to view sugar separately from the rest. Your glucose, your blood pressure and your fats together form a risk profile. Which blood values belong to it is covered in our piece on cardiovascular disease in men, and how cholesterol fits in cholesterol in men.

The message isn't that a high sugar makes you ill straight away. It's that it's one of the knobs that, turned in time, lowers several risks at once.

What can you do about your blood sugar yourself?

With blood sugar, lifestyle isn't a side note but the foundation. According to the RIVM, enough movement, a healthy weight and not smoking are the pillars that can shrink your risk of type 2 diabetes. It sounds dull, but the effect is often bigger than you'd expect from medication.

What often helps most is surprisingly simple: a walk around the block after dinner, fewer soft drinks and fast sugars, and slowly losing some weight around your middle. You don't have to do everything perfectly at once. Small, lasting steps weigh more than a strict diet you drop after three weeks.

In practice, a few things make the most difference: fewer fast sugars, more movement right after eating, and losing weight if you carry too much around the middle. How to do that smartly and what to measure next is covered in our piece on lowering blood sugar.

Important: these are general insights, not personal treatment advice. If you already take medication or have known diabetes, talk to your doctor before changing big things.

Blood sugar and your erection

This is the part many men would rather skip, but it matters. A long-term high blood sugar can damage the small blood vessels and nerves you need for an erection. That's why erectile problems are sometimes one of the first noticeable signals of a sugar problem.

That makes your erection a kind of unintended gauge for your blood vessels. If you notice a change, that's no reason for shame but a reason to look further. We explain the whole link between sugar and erections in our piece on diabetes and erectile problems.

For you as a man, this may be the most convincing reason not to ignore your blood sugar. It touches more than a number on paper.

When to have your blood sugar checked?

If you carry weight around your middle, diabetes runs in your family, or you recognise symptoms like thirst, fatigue or less interest in sex, it can help to have your blood sugar in view. Some men choose to check periodically, simply to know where they stand.

If you only want to look at your sugar balance, the Diabetes panel gives insight there. For the wider metabolic picture, the Metabolic Health Check also looks at your fats and weight context.

What you most want to avoid is walking around for years with a creeping raised blood sugar without knowing it. That's exactly the phase where the damage slowly builds and where you can also still do the most about it. One measurement gives you that clarity.

Don't see a raised blood sugar as an endpoint but as a starting point. It is exactly the kind of value that, if you know it in time, still leaves you plenty of room to act. Always discuss an unusual result with your GP, who can help you decide whether further steps are needed.

References

• Diabetes Fonds. What are normal blood sugar values? 2024. diabetesfonds.nl
• RIVM. Diabetes: figures and context. 2024. rivm.nl
• Knowler WC, et al. Reduction in the incidence of type 2 diabetes with lifestyle intervention or metformin. N Engl J Med. 2002. PMID 11832527.
• Nathan DM, et al. Translating the A1C assay into estimated average glucose values. Diabetes Care. 2008. PMID 18540046.

Every blood test result at Caliber includes a professional assessment by a BIG-registered doctor. For treatment decisions, always discuss your results with your GP.