Uric acid is a waste product in the body. Sometimes, uric acid can build up in the joints and tissues, causing a range of health problems. These include gout, a form of arthritis.
In this article, we list the typical low, normal, and high levels of uric acid for males and females. We also explain what health conditions are associated with having high or low levels.
Purines are chemical substances that occur naturally in the body and in some foods. When the body breaks down purines, this creates uric acid as a waste product. The kidneys filter it from the blood and pass it out of the body in the urine.
However, uric acid can sometimes build up in the blood. The medical term for this is hyperuricemia. It can occur if the body produces too much uric acid or does not get rid of enough of it.
Too much uric acid in the blood can lead to crystals forming in the joints and tissues, which may cause inflammation and gout symptoms.
Having some uric acid in the blood is normal. However, if uric acid levels go above or below a healthy range, this can result in health problems. High uric acid levels can increase the risk of gout.
It is unusual to have low uric acid levels, but it is possible if a person passes too much uric acid out of their body as waste.
The following table gives low, normal, and high levels of uric acid in the blood. All amounts are in milligrams per deciliter (mg/dl).
|Uric acid level||Males||Females|
|Low||Below 2.5 mg/dl||Below 1.5 mg/dl|
|Normal||2.5–7.0 mg/dl||1.5–6.0 mg/dl|
|High||Above 7.0 mg/dl||Above 6.0 mg/dl|
The causes of high uric acid levels are not always clear. However, genetics and environmental factors, such as diet and health, both play a part.
Risk factors for hyperuricemia include:
Gout is a form of arthritis. The symptoms come and go, usually affecting just one joint.
In people with this condition, uric acid builds up in the joints and tissues, causing pain, swelling, and discoloration. Gout most commonly affects the toe joints, ankles, and knees.
When cells die, they release purines. These release uric acid into the blood when the body breaks them down.
Some cancer treatments, such as chemotherapy, can cause cells in the body to die. Uric acid testing may be part of medical care for a person who has cancer.
The kidneys filter waste from the blood, including uric acid.
Kidney disease damages the kidneys and stops them from working normally. When this happens, waste products that include uric acid can build up in the blood.
Having low uric acid levels is rare.
The most prevalent medical condition causing low uric acid levels is Fanconi syndrome, a rare kidney disease. In people with this condition, the kidneys cannot absorb certain nutrients into the body.
Fanconi syndrome can cause a lack of energy, dehydration, and problems with the bones. A person with this condition will have low uric acid levels because too much of this substance is passing out of the body in the urine.
A person with high or low uric acid levels may not always have symptoms. Symptoms may not appear until a person has had levels outside the normal range for a long period, which can cause health problems.
Symptoms of gout, which is linked to high uric acid levels, include:
- painful or swollen joints
- joints that feel warm to the touch
- shiny, discolored skin around the joints
Symptoms of a kidney stone, which high uric acid levels can also cause, include:
- back pain
- pain in the side
- needing to pee more often
- urine that is cloudy, smells unusual, or contains blood
- nausea or vomiting
Low uric acid levels are less common than high ones. A person with low uric acid levels may urinate more than usual, which can cause dehydration if they are not drinking enough water.
A uric acid test measures the amount of uric acid in the blood or urine.
A person may need the test if they have gout symptoms or kidney stones or are undergoing cancer treatment. The test does not carry any risks.
A healthcare professional may take a small sample of blood with a needle or ask the person to collect their urine over a 24-hour period. Laboratory technicians will then test the sample for uric acid levels.
Doctors may sometimes also perform a joint aspiration, in which they use a needle and syringe to remove a small amount of fluid from the swollen joint. The presence of uric acid crystals in the fluid indicates gout.
If the doctor needs more information to diagnose health problems linked to uric acid levels, they may do a physical examination and ask questions about the person’s medical history and current symptoms.
Sometimes, a person will have high uric acid levels but no symptoms of a medical condition. They are unlikely to need treatment unless they develop symptoms.
Certain foods contain purines, which create uric acid when the body breaks them down. Eating a diet that is too rich in purines can cause uric acid to build up in the blood.
Foods that include moderate or high levels of purines include:
- organ meats
A person who has gout may wish to limit these foods in their diet.
Nonsteroidal anti-inflammatory drugs (NSAIDs) and steroids can reduce pain and inflammation, helping treat an acute gout flare.
People can also take steps to prevent gout flares. These include:
- avoiding alcohol
- reaching or maintaining a moderate weight
- protecting the joints with gentle, low impact exercise, such as walking, bicycling, and swimming
A person who has gout usually needs a uric acid test every 6 months.
Keeping uric acid levels within a certain range can reduce pain, joint damage, and complications from gout.
Uric acid is a waste product that can damage joints and tissue if it builds up too much in the body. When a person has high uric acid levels for an extended period, they may develop health problems.
If a person has gout, it is important for them to keep uric acid levels within a healthy range. Doing this can improve the symptoms and reduce the risk of a gout flare.