Understanding your blood

September 3rd, 2019
A lab technician prepares a blood sample in a lab.
Blood has four main components – red blood cells, white blood cells, platelets and plasma. Each component plays an important role in your health. Photo by iStock.

Coursing just below the surface of your skin is your body’s very own transportation highway: your blood.

Its brings oxygen and nutrients to cells, allows the brain and organs to communicate, and helps the immune system fend off illness. And one small vial of blood can reveal a lot about your health.

“It’s amazing how much we can test for in just a very small volume of blood,” said Dr. James Hopfenbeck, a pathologist at UCHealth Yampa Valley Medical Center. “Here at our own lab, we can do 40 different tests using one little vial of blood.”

Hopfenbeck outlines what you need to know about blood below.

The components

Blood has four main components – red blood cells, white blood cells, platelets and plasma.

Red blood cells make up 40 to 45% of blood’s volume and contain hemoglobin, a special protein that helps carry oxygen to your cells and gives your blood its red color. People living at altitude typically have extra red blood cells since the air is thinner.

“Our body compensates by producing more red blood cells so we have enough oxygen transported to our tissues and organs,” Hopfenbeck said.

White blood cells are key parts of your immune system, identifying and attacking foreign materials such as bacteria and viruses. They make up 1% of your blood volume.

Platelets are fragments of cells that help with clotting. “If you have a cut or an ulcer, platelets form a plug in the blood vessel to stop your bleeding,” Hopfenbeck said.

Finally, plasma is a mixture of water, sugar, fat, protein and salts, and moves blood cells, platelets, hormones and waste products around the body.

Blood Types

There are thousands of different subtypes of blood, but only four main groups – group A, group B, group O and group AB. Your blood type is determined by your genes, and refers to the type of sugar you have on the surface of your red blood cells.

“Blood type doesn’t have anything to do with your health, but is important to know for transfusions,” Hopfenbeck said. “If you’re a group A person, then your body naturally produces antibodies to group B antigen. So if you receive group B blood, your body will destroy those cells because they’ll look foreign.”

People who are in group O are considered universal donors because they don’t have any sugars on the surface of their blood, so their blood is accepted by everyone.

Keeping your blood healthy

Eating a healthy diet and exercising regularly benefits your blood.

“You need your basic nutrients, such as iron, folate, vitamin B12 and other vitamins and minerals,” Hopfenbeck said. “And exercise changes the blood by stimulating fat metabolism and helping your body use nutrients better.”

Blood tests

“We can measure very small quantities of chemicals in the blood to know whether organs such as your kidneys and liver are functioning well, whether your cholesterol is at the right level and if you have signs of adult-onset diabetes,” Hopfenbeck said. “These give a snapshot of how the organs are working.”

For instance, higher-than-normal levels of prostate-specific antigen (PSA) may be a sign of prostate cancer. Levels of TSH can reflect how well your thyroid is functioning. And a build-up of certain waste products may suggest your kidneys aren’t working well.

Not only are the tests powerful, picking up tiny amounts of various chemicals, but they’re also often fast.

“We can get many tests done in 20 minutes,” Hopfenbeck said.

 

This article first appeared in the Steamboat Pilot & Today on Sept. 2, 2019.

About the author

Susan Cunningham lives in the Colorado Rocky Mountains with her husband and two daughters. She enjoys science nearly as much as writing: she’s traveled to the bottom of the ocean via submarine to observe life at hydrothermal vents, camped out on an island of birds to study tern behavior, and now spends time in an office writing and analyzing data. She blogs about writing and science at susancunninghambooks.com.