There are several types of blood tests that can give you a picture of your general health. What do the top 5 blood tests and their results mean for you?

Blood tests are one way for your doctor to get a good picture of your general health. These top five blood tests show how your internal organs are working and are markers for various conditions such as heart disease or diabetes.

“It’s important to stay on top of your health, and getting these types of blood tests is one way to do it,” said Monalisa M. Tailor, M.D., an internal medicine physician with Norton Community Medical Associates primary care.

Why do I need blood tests?

There are many reasons why your primary care provider (PCP) might order a blood test for you. The top five most common blood tests measure everything from platelets and blood cell count to enzymes, liver proteins and your blood glucose level.

There are several types of blood tests, and you may need one because:

• It’s part of your routine exam, and your PCP would like to know more about your blood, including a complete blood count (CBC), a basic metabolic panel (BMP) or a comprehensive metabolic panel (CMP). 
• You need a screening test to see if you are at risk for certain diseases or conditions, such as kidney or heart disease.
• Blood testing can show if certain treatments you are receiving are working: gout, diabetes or cancer treatment, for example.
• You have a condition, such as diabetes, and need to check a part of your blood’s makeup such as blood glucose. High glucose can affect many organs, including your heart, eyes and kidneys, and even your feet.
• You need to be checked for vitamin deficiencies, such as low vitamin D or vitamin B12.

Complete blood count (CBC)

These types of blood tests measure various parts of the blood, such as your white blood cell count. The normal range may vary slightly from one laboratory to another. The general ranges for pertinent lab values are listed below.

White blood cells: These are immune cells that attack viruses, bacteria and other invaders.	4,500 to 11,000 per microliter (mm3)
Hemoglobin: This is a protein that helps red blood cells carry oxygen to organs and tissues and take carbon dioxide to the lungs.	150,000 to 400,000 per mm3
Hematocrit: This refers to how much of the overall blood is made of red blood cells.	male: 41% to 53%; female: 36% to 46%
Platelets: They control blood clotting.	male: 13.5 to 17.5 grams per deciliter (g/dL); female: 12.0 to 16.0 g/dL

Basic metabolic panel (BMP)

“This test tells you if you are anemic, have a clotting disorder or have issues with fighting off infection,” Dr. Tailor said.

A BMP checks for:

Glucose, which is a type of sugar, is your body and brain’s main source of energy: High glucose can signal something serious.

Calcium, which is one of the body’s most important minerals: Calcium is essential for proper functioning of your nerves, muscles and heart.

Sodium, potassium, carbon dioxide and chloride: These are electrolytes, electrically charged minerals that help control the amount of fluids and the balance of acids and bases in your body.

Blood urea nitrogen (BUN) and creatinine are waste products removed from your blood by your kidneys: Sometimes the BUN can be higher if you are fasting for your bloodwork.

Glomerular filtration rate (GFR): This is a calculation of your kidney function.

“We look for any abnormalities in these substances,” Dr. Tailor said. “A BMP checks everything from kidney health and fluid balance to blood sugar levels and metabolism.”

Comprehensive metabolic panel

The CMP includes the measures for the BMP (above) as well as proteins and substances related to how well the liver is performing.

A CMP blood test measures:

	High levels	Low levels
Alkaline phosphatase (ALP) — an enzyme found in bones and liver	• Bile duct blockage • Cirrhosis • Gallbladder inflammation • Gallstones • Hepatitis • Paget’s disease	• Bone metabolism disorders • Hypothyroidism • Malnourishment • Zinc deficiency
Alanine aminotransferase (ALT) — a liver enzyme	• Cirrhosis • Hepatitis • Liver cancer • Liver damage	Considered normal
Aspartate aminotransferase (AST) — an enzyme in body tissue, including the liver	• Cirrhosis • Heart conditions • Hepatitis • Mononucleosis (mono) • Pancreatitis	Considered normal
Bilirubin — the waste from red blood cells breaking down and filtered by the liver	• Abnormal red blood cell destruction (hemolysis) • Adverse medication reactions • Bile duct blockage • Gilbert syndrome • Hepatitis	Not a concern

Lipid panel

A lipid panel is a blood test that looks at two types of cholesterol in the blood: high-density lipoprotein (HDL), often referred to as “good” cholesterol, and low-density lipoprotein (LDL), often referred to as the “bad” cholesterol. Physical activity improves HDL.

Typically, you will be asked to refrain from eating or drinking anything except water for eight to 12 hours before a lipid panel test. The results are reported as milligrams per deciliter (mg/dL).

Total cholesterol:

• Optimal: About 150

LDL cholesterol:

• Optimal: Less than 100
• Near optimal: 100 to 129
• Borderline high: 130 to 159
• High: 160 to 189
• Very high: 190 or above

HDL cholesterol:

• Low (considered a risk factor for heart disease): Less than 40
• Good (able to help lower your risk for heart disease): 60 or more

Thyroid test

Your thyroid is a gland in your neck. It helps regulate bodily functions like your mood, energy level and overall metabolism. A thyroid panel, or thyroid function test, checks how well the thyroid is producing and reacting to certain hormones, such as: 

Triiodothyronine (T3): Along with T4, this regulates heart rate and body temperature.

Thyroxine (T4): Along with T3, this regulates metabolism and growth.

Thyroid-stimulating hormone (TSH): Produced by the pituitary gland in your brain, it helps regulate the levels of hormones the thyroid releases.

Here are normal results:

T3: 80 to 180 nanograms per deciliter of blood (ng/dL)

T4: 0.8 to 1.8 ng/dL in adults

TSH: 0.5 to 4 milli-international units per liter of blood (mIU/L)

Abnormal levels of these hormones can indicate many conditions, such as:

• Low protein levels
• Thyroid disorders
• Abnormal levels of testosterone or estrogen

How often should I get blood tests?

“For most healthy adults, I would recommend once a year. You can schedule blood tests when you have your routine annual physical,” Dr. Tailor said.

“I always remind patients that providers get test results at the same time, so please allow 48 hours for me to review and help you understand the results and next steps,” she said.

Blood test results usually come back within one to three days and can be seen when you sign in to your Norton MyChart account.