Men's health after 40: the blood numbers worth tracking

Most men over 40 feel much the same as they did at 30. Inside, things are often changing. Cholesterol creeps up, blood sugar control loosens, the liver stores more fat and hormones begin a slow decline. None of this causes symptoms at first, which is exactly why a yearly blood test is useful.

These are the numbers on the Well Man panel that are most worth watching from your 40s onwards, with the guideline limits LifePrint uses.

Cholesterol and blood fats

Heart disease is one of the leading causes of death in South African men, and raised cholesterol is one of its main drivers. LifePrint uses the SA Heart and Lipid and Atherosclerosis Society of Southern Africa 2018 guideline:

• LDL cholesterol below 3.0 mmol/L for men at low to moderate risk. A doctor may set a lower target if your risk is higher.
• HDL cholesterol above 1.0 mmol/L for men.
• Triglycerides below 1.7 mmol/L, fasting.
• Total cholesterol below 5.0 mmol/L.

Cholesterol is only one part of heart risk. Blood pressure, smoking, diabetes and family history all count, and a doctor combines them to estimate your overall risk.

Blood sugar

Type 2 diabetes becomes more common with each decade and often goes undiagnosed for years. HbA1c shows your average sugar over about three months, and fasting glucose shows this morning's level. Following SEMDSA 2017, an HbA1c of 6.0 to 6.4% or a fasting glucose of 6.1 to 6.9 mmol/L means you are at risk. An HbA1c of 6.5% or more, or a fasting glucose of 7.0 mmol/L or more, is in the diabetes range and needs confirming.

Liver

ALT and GGT are the liver enzymes most likely to rise with fatty liver and alcohol. LifePrint uses the American College of Gastroenterology 2017 limit of 33 U/L for ALT in men, which is stricter than many lab ranges. Mild rises are common and should be repeated before any investigation.

Kidneys

eGFR estimates how well your kidneys filter the blood. It falls slowly with age, and faster with high blood pressure or diabetes. Following KDIGO 2024, a value of 60 to 89 is mildly decreased and usually normal for age. Below 60, confirmed over three months, is in the chronic kidney disease range.

Testosterone

Testosterone falls gradually from middle age, and faster with weight gain, poor sleep and illness. LifePrint uses the Endocrine Society's range of 9.2 to 31.8 nmol/L, with a grey zone of 9.2 to 12 nmol/L. A low result always needs a second morning, fasting sample before any conclusion. Our article on testing testosterone covers this in detail.

PSA

PSA is included in Well Man from age 40. LifePrint compares it with an age-specific upper limit, starting at 2.5 ug/L for men under 50. A baseline in your 40s gives you a personal reference point for later years. Because PSA testing has both benefits and downsides, it is a choice to talk through with a doctor.

Blood count, iron, thyroid and vitamin D

• Haemoglobin: the WHO defines anaemia in men as below 13.0 g/dL. Unexplained anaemia in a man over 40 always deserves a doctor's attention, because it can point to hidden blood loss from the gut.
• Ferritin: shows iron stores. Low ferritin in a man is uncommon and should be explained. A very high ferritin can point to inflammation, liver disease or iron overload.
• TSH: screens thyroid function, which affects energy, weight and cholesterol.
• Vitamin D: the Institute of Medicine regards 50 nmol/L or more as sufficient.
• hs-CRP: a marker of low-grade inflammation. Following the AHA and CDC, below 1 mg/L is lower cardiovascular risk and above 3 mg/L is higher.

What a blood test does not cover

Some of the most important checks after 40 are not blood tests at all. Blood pressure, waist size, a skin check, and bowel cancer screening from the age your doctor advises all matter. A blood test is a strong starting point, not the whole picture.

What to do with your results

Your LifePrint report flags results outside the range, shows grey zone results separately, and tells you how urgently to follow up. Bring any flagged results to a registered healthcare practitioner, ideally with your previous results so the trend can be seen. This is health information, not a diagnosis.