Preventive Health Guide
5 Health Numbers Worth Knowing Before You Turn 40
Your blood pressure, blood sugar, cholesterol, body measurements and kidney function can provide useful clues about your health. Knowing these numbers before you turn 40 can help you discuss potential health risks with your doctor and decide whether further assessment is needed.
Quick Answer: Which Health Numbers Should You Know?
Before turning 40, consider knowing your blood pressure, blood glucose, cholesterol levels, body mass index (BMI) and waist circumference, and kidney function results such as creatinine and estimated glomerular filtration rate (eGFR). These measurements help assess different aspects of health. The right tests depend on your age, medical history and risk factors.
Why Are These Health Numbers Important?
Some health conditions, including high blood pressure, abnormal blood sugar and high cholesterol, may develop without obvious symptoms. Routine health checks can help identify potential concerns before they become more serious.
You do not need to wait until you turn 40 to start monitoring your health. Your doctor can advise which measurements and blood tests are appropriate based on your personal risk factors.
Number 01
Blood Pressure
Blood pressure measures the force of blood against the walls of your arteries. It is recorded using two numbers: systolic pressure, the pressure when your heart beats, and diastolic pressure, the pressure between beats.
A commonly used reference for normal adult blood pressure is below 120/80 mmHg. Consistently elevated readings may require assessment, but one measurement alone is not enough to diagnose hypertension.
What to do: Sit quietly for several minutes before measurement, keep your feet flat on the floor and use a properly fitted cuff. Your doctor may recommend repeated home readings.
Number 02
Blood Sugar
Blood glucose measures the amount of sugar in your blood. Testing may help identify prediabetes or diabetes, particularly if you have risk factors such as a family history of diabetes, excess weight or a history of gestational diabetes.
Common tests include fasting plasma glucose and HbA1c. HbA1c reflects average blood glucose over approximately the previous two to three months.
| Test | Common reference information |
|---|---|
| Fasting blood glucose | Below 5.6 mmol/L is generally considered normal under commonly used criteria. |
| HbA1c | Below 5.7% is generally considered normal under commonly used criteria. |
Important: Diagnostic thresholds can vary by guideline and clinical circumstances. Your doctor may recommend repeat testing to confirm an abnormal result.
Number 03
Cholesterol
Cholesterol is a fatty substance your body needs, but unhealthy levels can contribute to plaque build-up in your arteries. A lipid profile usually measures total cholesterol, LDL cholesterol, HDL cholesterol and triglycerides.
LDL is often called “bad” cholesterol because higher levels can contribute to artery plaque. HDL helps transport cholesterol back to the liver, while triglycerides are another type of fat in the blood.
The appropriate cholesterol target depends on your overall cardiovascular risk, including blood pressure, diabetes, smoking status and family history. People at higher risk may need lower LDL targets.
What to do: Ask your doctor whether a lipid profile is appropriate for you and how your results should be interpreted alongside your other risk factors.
Number 04
BMI and Waist Circumference
Body mass index (BMI) estimates weight in relation to height. Waist circumference provides another measurement that can help assess abdominal fat and related metabolic risk.
For adults, standard international BMI categories commonly classify 18.5–24.9 as the healthy-weight range. However, Asian populations may have increased metabolic risk at lower BMI values, so locally relevant criteria may be used.
| BMI (kg/m²) | Common international category |
|---|---|
| Below 18.5 | Underweight |
| 18.5–24.9 | Healthy weight |
| 25.0–29.9 | Overweight |
| 30.0 or above | Obesity |
Remember: BMI is a screening measure, not a diagnosis. It does not directly measure body fat or distinguish muscle from fat. Your doctor may also consider waist circumference, blood pressure, blood sugar and cholesterol.
Number 05
Kidney Function: Creatinine and eGFR
Your kidneys filter waste and excess fluid from your blood. A kidney function assessment commonly includes blood creatinine and estimated glomerular filtration rate (eGFR).
Creatinine is a waste product measured in the blood. eGFR estimates how well your kidneys filter blood, using creatinine and other information such as age and sex, depending on the equation used.
An eGFR of 90 or above is generally within the normal range, but it does not rule out kidney disease. Persistent eGFR below 60, or other signs of kidney damage lasting at least three months, may indicate chronic kidney disease and require medical assessment.
What to do: If you have diabetes, high blood pressure, cardiovascular disease or a family history of kidney disease, ask your doctor whether kidney function and urine albumin testing are appropriate.
Health Screening in Johor Bahru
If you live or work in Johor Bahru, routine health screening can help establish a baseline and identify results that may need follow-up. Depending on your health profile, screening may include blood pressure measurement, blood glucose testing, a lipid profile and kidney function tests.
At Southern Health Centre, you can enquire about available preventive health screening options and discuss which assessments may be suitable for your needs. The appropriate tests depend on your medical history, symptoms and individual risk factors.
Summary: Five Health Numbers to Discuss With Your Doctor
| Health measurement | What it helps assess | Common test or method |
|---|---|---|
| Blood pressure | Pressure in your arteries | Blood pressure measurement |
| Blood sugar | Glucose regulation and diabetes risk | Fasting glucose or HbA1c |
| Cholesterol | Cardiovascular risk | Lipid profile |
| BMI and waist | Weight-related and abdominal-fat risk | Height, weight and waist measurement |
| Kidney function | Kidney filtration and possible damage | Creatinine, eGFR and sometimes urine albumin |
These measurements provide different information and should not be interpreted in isolation. Your doctor can explain your results and recommend a follow-up plan if needed.
Know Your Numbers. Take Charge of Your Health.
Start with a discussion about your health history and screening needs. Contact Southern Health Centre to enquire about available health screening options in Johor Bahru.
Enquire About Health ScreeningFrequently Asked Questions
What health checks should I have before turning 40?
Depending on your age and risk factors, your doctor may recommend blood pressure measurement, blood glucose testing, cholesterol screening, BMI and waist assessment, and kidney function tests. Other checks may be appropriate based on your family history, symptoms and medical background.
How often should I check my blood pressure?
The frequency depends on your previous readings and risk factors. Adults with normal readings may need less frequent checks than those with elevated blood pressure or related medical conditions. Follow your healthcare professional's advice.
Can I have high blood sugar without symptoms?
Yes. Prediabetes and type 2 diabetes may develop without noticeable symptoms. Blood tests can help identify abnormal glucose levels, especially in people with risk factors.
Do I need to fast before a health screening blood test?
Not every blood test requires fasting. Fasting may be requested for certain glucose tests and sometimes lipid testing, depending on the clinical purpose. Confirm the preparation instructions with your healthcare provider before your appointment.
Does a normal kidney blood test mean my kidneys are healthy?
Not always. Creatinine and eGFR provide useful information, but kidney disease may also be associated with urine albumin or other findings. Your doctor may recommend additional tests based on your risk factors and results.
Where can I get a health screening in Johor Bahru?
You can contact Southern Health Centre in Johor Bahru to enquire about available health screening services. Ask which tests are included, whether fasting is needed and whether a consultation to review your results is available.
