All About Blood Tests

All About Blood Tests

Blood tests can be used to help a doctor identify a variety of health conditions, including vitamin deficiencies, organ failure, HIV, cancer, diabetes, and more.

What is a blood test?

Regular blood testing is one of the most important ways to keep track of your overall physical well-being. Getting tested at routine intervals can allow you to see the way your body changes over time and empower you to make informed decisions about your health.

What does a blood test show?

Some blood tests can help  determine how different organs are working. Examples of organs whose malfunctions can be visible in a blood test includeTrusted Source your thyroid, liver, or kidneys.

We can also use blood tests to search for markers of diseases and health conditions such as:

diabetes

HIV

anemia

cancer

coronary heart disease

Even if a person does not have heart disease, a blood test can show whether they may be at risk of developing the condition.

10 important blood tests

1. Complete blood count

A routine complete blood count (CBC) checks for levels of 10 different components of every major cell in your blood: white blood cells, red blood cells, and platelets.

Important components this test measures include red blood cell count, hemoglobin, and hematocrit.

Here’s the typicalTrusted Source range of results, although every laboratory may have its own range that varies slightly:

Component   Normal range

red blood cells (cells responsible for carrying oxygen throughout the body)       male: 4.3–5.9 million/mm3; female: 3.5–5.5 million/mm3

white blood cells (immune system cells in the blood)      4,500–11,000/mm3

platelets (the substances that control the clotting of the blood)    150,000–400,000/mm3

hemoglobin (protein within the red blood cells that carries oxygen to organs and tissues, and carbon dioxide back to the lungs)  male: 13.5–17.5 grams/deciliter (g/dL); female: 12.0–16.0 g/dL

hematocrit (percentage of blood made of red blood cells)    male: 41–53%; female: 36–46%

Abnormal levels of these components may indicate:

nutritional deficiencies, such as vitamin B6 or B12

anemia (iron deficiency)

clotting problems

blood cancer

infection

immune system disorders

2. Basic metabolic panel

A basic metabolic panel (BMP) usually checks for levels of eight compounds in the blood:

calcium

glucose

sodium

potassium

bicarbonate

chloride

blood urea nitrogen (BUN)

creatinine

Abnormal results may indicate:

kidney disease

diabetes

hormone imbalances

3. Comprehensive metabolic panel

A comprehensive metabolic panel (CMP) includes all the measurements of a BMP as well as additional proteins and substances related to liver function, such as:

albumin

total protein

alkaline phosphatase (ALP), an enzyme mostly found in the bones and liver that’s involved in several bodily processes

alanine aminotransferase (ALT), an enzyme found in the liver

aspartate aminotransferase (AST), an enzyme found in the liver and other tissues within the body

bilirubin, which is waste resulting from the breakdown of red blood cells that the liver filters out

The same conclusions can be drawn from a CMP as from a BMP for the same substances that a BMP covers. Other abnormal levels can also indicate underlying conditions, such as:

4. Lipid panel

This test checks levels of two typesTrusted Source of cholesterol:

high-density lipoprotein (HDL), or “good” cholesterol

low-density lipoprotein (LDL), or “bad” cholesterol

HDL is “good” because it removes harmful substances from your blood and helps the liver break them down into waste. LDL is “bad” because it can cause plaque to develop in your arteries, increasing your risk of heart disease.

Here are the ranges Trusted Source for each type: