Blood sample in a tube

BUN Test: Everything You Need To Know

October 21, 2020

The blood urea nitrogen (BUN) test is used to determine how well your kidneys are working. The main job of the bean-shaped organs is to filter waste and water from the blood to make urine. This test is an effective way to determine whether the kidneys are working on all cylinders.

What Does the Kidney Do?

The kidneys are organs we’ve heard about but might be unsure exactly what they do. The main job of the kidneys is to form urine by removing wastes as well as extra water from a person’s blood. Urine flows to the bladder from the kidneys via the “ureters.”

Waste that’s in the blood is from sources like the food you eat and the break-down of muscles. Your body first gets the nutrients it needs for energy and fixing itself. Then the waste leftover gets sent to your blood.

Nephrons, a functional unit in the kidneys, filter out the wastes. Every human kidney has around one million nephrons.

Here’s how it works. Small blood vessels in the nephron work with urine-carrying tubes. There’s a chemical reaction, which causes waste/water to leave the blood and turn into the urine.

The body sends some stuff back to the body like sodium and potassium. The body needs to have the right balance of these substances. If it doesn’t then it can be dangerous to the body and cause health problems.

The kidneys keep busy and also have another job. They release 3 key hormones. This includes a form of Vitamin D, which helps to maintain calcium levels for the bones.

Interestingly, two healthy kidneys are more than a person’s needs. Some people live with one kidney their whole lives and never have any health problems.

However, you can experience issues like kidney disease, which affects how well your organs can filter waste. Symptoms of early kidney disease include vomiting, nausea, numbness, drowsiness, cramps, and lack of focus.

What’s The BUN Test?

This is a blood urea nitrogen (BUN) test that helps to determine whether or not your kidneys are

functioning properly. That’s done by checking the level of “urea nitrogen” that’s contained in your blood.

This is a type of waste that the liver makes when breaking down proteins. When the kidneys are working properly, they filter out the good stuff then urine takes out the waste from the body.

If your kidneys or liver get damaged then this usually results in higher BUN levels. So, if you have this result then there’s a good chance you have liver or kidney problems. Your doctor will likely order other tests to try and pinpoint exactly what the problem is.

Here’s how the test is conducted. It’s usually performed to check how well the kidneys are functioning. The BUN test is frequently done with other blood tests to provide an accurate diagnosis. Here are some of the things it checks:

The tests are also done for other reasons. They include checkups and hospital stays. If you have other conditions like diabetes then BUN tests also might be run.

One key feature of the BUN test is there’s no special prep required. That said, it’s critical to inform your physician if you’re currently taking any over the counter (OTC) or prescription meds. That’s because some meds could increase or decrease your BUN results.

The BUN test results are measured in milligrams/deciliter (mg/dL). Take note that values usually are different based on gender and age. Another factor is “normal” ranges for each lab that processes the test.

High test results can point to conditions like:

  • Heart disease
  • Heart failure
  • Dehydration
  • Kidney disease
  • High protein
  • Stress
  • Urinary tract problem

Meanwhile, low BUN levels can be signs of liver failure, malnutrition, overhydration, and lack of protein.

BUN Results and Healthy Kidneys

It’s important to have your doctor review the test results with you. It’s important to know what they likely mean. Keep in mind that your doctor might order other tests to verify whether or not you have a particular condition or not.

In some cases, you don’t have health problems, but a high/low result could show certain things. They include dehydration, high protein level, pregnancy, or aging. These are long-term health conditions but could temporarily affect your BUN test results.

You also might experience some possible side-effects from the BUN test. They include bruising, bleeding, infection, and blood buildup, where the test was conducted. Sometimes people feel dizzy when blood is removed from their body.

It’s important to inform your doctor of any major side-effects you had from the test.

The BUN test is a basic one that usually allows you to return to your day-to-day activities. There are some situations when more tests are ordered, and especially if there are signs you might have a serious health condition.

You can also take steps after the exam to help maintain healthy kidneys. They include:

1. Exercise more

It’s important to exercise regularly. This provides various benefits, including more muscle strength, lower blood pressure, lower cholesterol levels, balanced blood sugar levels, and lower body weight.

2. Eat a balanced diet

Make sure you’re eating healthy for your kidney and heart. Avoid processed foods and pick fresh fruits/veggies, limit your salt intake, and avoid high-fat/cholesterol foods like fried foods.

Another important kind of food is omega-3 foods. These include fatty fish, olive oil, avocados, and walnuts.

3. Reduce blood pressure

If you have high blood pressure then take steps to reduce it. For example, there are blood pressure pills for people with kidney disease, which can provide help like the bun test.