Turning 40 doesn't mean something suddenly changes overnight—but it can be a good time to start paying closer attention to the numbers you can't see in the mirror.
Blood pressure, cholesterol, blood sugar, hormone levels, kidney function and other health markers can change without producing obvious symptoms.
That's where blood testing can be useful.
Routine blood work can provide information about what's happening inside your body and may identify results worth discussing with your healthcare provider.
That doesn't mean every man over 40 needs every test on this list. Your medical history, family history, symptoms, medications and individual risk factors all matter.
Here are seven blood tests men over 40 should know about.
1. Complete Blood Count (CBC)
A Complete Blood Count, commonly called a CBC, is one of the most frequently performed blood tests.
It measures several components of your blood, including:
Red blood cells
White blood cells
Hemoglobin
Hematocrit
Platelets
A CBC can provide useful information when evaluating anemia, infections and certain blood abnormalities.
For men experiencing unexplained tiredness or reduced energy, a CBC may also be one of several tests considered when investigating possible causes.
If fatigue is something you've been experiencing, read our guide Feeling Tired All the Time? 7 Blood Tests That May Help You Find Out Why.
→ Explore CBC and general health blood tests
2. Cholesterol and Lipid Panel
High cholesterol doesn't necessarily make you feel unwell.
That's one reason knowing your cholesterol numbers can be useful.
A typical lipid panel measures:
Total cholesterol
LDL cholesterol
HDL cholesterol
Triglycerides
These results are considered alongside other cardiovascular risk factors such as blood pressure, diabetes, smoking, age and family history.
If you've already discovered that your cholesterol is elevated, our Top 10 Tips to Manage High Cholesterol explains some of the lifestyle and treatment considerations involved.
→ Explore cholesterol and cardiac health tests
3. Blood Glucose and Hemoglobin A1c
Blood sugar is another number worth understanding as you get older.
A standard glucose test measures the amount of glucose in your blood at the time the sample is collected.
Hemoglobin A1c (HbA1c) provides different information. It reflects average blood glucose over approximately the previous two to three months.
A1c testing is commonly used when screening for or monitoring prediabetes and diabetes.
Risk can be influenced by factors including:
Age
Weight
Physical activity
Family history
Blood pressure
Previous blood glucose results
A person can have elevated blood glucose without immediately noticing obvious symptoms.
→ Compare diabetes and blood glucose tests
4. Testosterone
Testosterone is probably one of the first blood tests many men think about when discussing health after 40.
Testosterone levels generally change with age, but age alone isn't a reason to assume that someone has low testosterone.
Testing may be considered when symptoms or other clinical circumstances warrant investigation.
Symptoms sometimes associated with low testosterone can include:
Reduced sex drive
Changes in energy
Reduced muscle mass
Erectile difficulties
Changes in mood
However, these symptoms can have many other causes.
That's particularly important with fatigue. Feeling tired doesn't automatically mean testosterone is low.
USLabTesting lists several testosterone testing options, including Total Testosterone, Free Testosterone and broader hormone panels.
→ Compare testosterone blood tests
For men interested in a broader hormone assessment:
→ View the Comprehensive Male Hormone Panel
5. Kidney Function Tests
Your kidneys perform the essential job of filtering waste and excess fluid from your blood.
Kidney-related blood testing commonly involves measurements such as:
Creatinine
Blood urea nitrogen (BUN)
Estimated glomerular filtration rate (eGFR)
Electrolytes
Urine testing can provide additional information about kidney health.
Kidney testing may be particularly relevant for people with certain risk factors, including diabetes and high blood pressure.
Creatinine is one of the most familiar kidney-related markers, but the result isn't always straightforward—particularly for people with greater muscle mass or those using creatine supplements.
For a deeper explanation, read Understanding Creatinine: What It Is and Its Importance – Body Building and Creatine Supplements.
You can also read Signs of Kidney Disease: Recognizing the Early Warning Signs.
→ Compare kidney and liver tests
USLabTesting also lists a dedicated Renal (Kidney) Function Panel.
→ Browse kidney function testing options
6. Liver Function Tests
Your liver performs hundreds of functions, including processing nutrients, producing important proteins and helping your body process medications and other substances.
Blood testing can provide information about liver health through measurements such as:
ALT
AST
ALP
Bilirubin
Albumin
Total protein
Abnormal results don't automatically mean you have liver disease. Exercise, medications, alcohol use and other factors can sometimes affect particular measurements.
USLabTesting offers both individual liver-related tests and broader liver function testing.
→ Compare liver function blood tests
If you want to understand liver blood tests in more detail, USLabTesting also has an existing guide covering liver health, diagnostic testing and common liver conditions in the blog.
Another useful article is the USLabTesting guide to the FIB-4 Index, which explains how measurements including AST, ALT and platelet count can be used in a calculation associated with liver fibrosis assessment.
→ Browse USLabTesting health articles
7. Comprehensive Metabolic Panel (CMP)
If you don't know exactly what you want tested, a broader health panel can sometimes provide more useful information than focusing on one individual marker.
A Comprehensive Metabolic Panel (CMP) measures multiple substances and provides information related to areas including:
Blood glucose
Electrolytes
Calcium
Kidney function
Liver function
Blood proteins
It's commonly included as part of broader routine blood work.
→ Compare general health and wellness tests
What About PSA Testing After 40?
PSA stands for prostate-specific antigen.
A PSA blood test measures PSA in the blood and can form part of prostate cancer screening discussions.
However, PSA testing isn't simply a test that every man should automatically order at a particular birthday.
The decision can depend on factors such as age, family history and individual risk. PSA results also aren't specific to cancer; non-cancerous conditions can affect PSA levels.
Because prostate screening involves potential benefits and limitations, it's worth discussing your individual circumstances with a healthcare professional.
USLabTesting lists PSA testing among its available health-testing options.
→ Explore general health and wellness testing
Can You Check Several of These at the Same Time?
Yes.
This can make more sense than ordering a long list of individual tests.
For example, the USLabTesting Standard Health Panel combines:
Complete Blood Count (CBC)
Comprehensive Metabolic Panel (CMP)
Urinalysis (UA)
Lipid Panel
Thyroid-Stimulating Hormone (TSH)
→ View the Standard Health Panel
For people who want a broader set of measurements, USLabTesting also lists a Comprehensive Health Panel that adds iron testing to several common health markers.
→ Compare General Health & Wellness Panels
There are also male wellness panels that combine several health markers relevant to men.
→ Browse male wellness and general health testing
What If You Feel Healthy?
That's an important question.
You don't necessarily need to feel unwell before discussing preventive health screening.
Some measurements—such as cholesterol or blood glucose—can be outside desirable ranges without causing obvious symptoms.
At the same time, ordering as many tests as possible isn't automatically better.
Testing is most useful when there is a reason for the test and you understand what you'll do with the result.
Your healthcare provider can help determine which screenings are appropriate based on your age, medical history, family history and individual risk factors.
What If You're Tired, Gaining Weight or Just Don't Feel Like Yourself?
This is where people sometimes jump immediately to testosterone.
But fatigue and reduced energy aren't specific to low testosterone.
Depending on the individual, a healthcare professional might consider several possibilities and tests, including:
CBC
Thyroid testing
Iron and ferritin
Vitamin B12
Vitamin D
Blood glucose
Testosterone
Kidney and liver function
If that's closer to why you're researching blood testing, read Feeling Tired All the Time? 7 Blood Tests That May Help You Find Out Why next.
Can You Order Your Own Blood Tests?
Depending on the test and applicable requirements, consumers in many parts of the United States can purchase certain laboratory tests directly.
That can be useful for people who want to investigate a particular health marker, monitor something they've previously tested or obtain results to discuss with their healthcare provider.
Before ordering, make sure you understand:
What the test measures
Which biomarkers are included
Whether fasting is required
Where the specimen will be collected
How you'll receive your results
Whether follow-up or interpretation is included
Prices and included biomarkers can vary between tests and providers, so compare the details rather than choosing based only on the test name.
→ Browse All Lab Tests on USLabTesting
The Bottom Line
After 40, understanding basic health numbers can become increasingly useful—but there isn't one universal blood-testing package that's right for every man.
CBC, cholesterol, blood glucose, kidney, liver and metabolic testing are among the tests you may encounter during routine health assessments. Testosterone and other hormone testing may also be appropriate when symptoms or individual circumstances warrant it.
Rather than testing everything, focus on tests that are relevant to your health, risk factors and goals.
If you want to compare several commonly used health tests in one place:
→ Compare General Health & Wellness Tests
Or, if low energy is your main concern:
→ Read: 7 Blood Tests That May Help Investigate Fatigue
Important Medical Disclaimer
This article is provided for general informational and educational purposes only and is not intended to provide medical advice, diagnosis or treatment. Screening and laboratory-testing needs vary between individuals. Discuss your health, symptoms, risk factors and test results with an appropriately qualified healthcare professional.