Uric Acid

Breakdown product of purines; high values can be associated with gout.

What it is

Uric acid is a natural waste product that forms when your body breaks down substances called purines. Purines are found naturally in your body and also in certain foods. Most uric acid dissolves in your blood, travels to your kidneys, and is then passed out of your body in your urine. If your body produces too much uric acid or your kidneys don't remove enough of it, it can build up in your blood. This is known as hyperuricaemia.

Why it matters

Having a certain level of uric acid in your blood is normal and necessary. However, persistently high levels of uric acid can sometimes lead to health issues. The most well-known condition associated with high uric acid is gout. Gout is a type of inflammatory arthritis that can cause sudden, severe attacks of pain, redness, and tenderness in the joints, often affecting the big toe. This happens when uric acid crystals form in the joints.

High uric acid levels can also be linked to other health conditions, including kidney stones and, in some cases, may be associated with an increased risk of cardiovascular disease and chronic kidney disease. Your doctor will consider your uric acid level alongside other health information to get a complete picture of your health.

The typical reference range for uric acid in the blood for adults in the UK is generally between 200 and 430 micromoles per litre (µmol/l). However, this can vary slightly between laboratories, so it's always best to refer to the specific range provided on your test report.

What can cause it to be high or low

Several factors can influence your uric acid levels.

Factors that can lead to higher uric acid levels include:

• Diet: Consuming a diet rich in purine-containing foods, such as red meat, organ meats (like liver and kidneys), and certain seafood (like anchovies and sardines), can increase uric acid production. Alcohol, particularly beer, can also raise uric acid levels.
• Medical conditions: Certain health conditions can affect uric acid levels. These include high blood pressure, diabetes, metabolic syndrome, and conditions that affect kidney function. Blood cancers like leukaemia and lymphoma, and conditions that cause rapid cell turnover, such as psoriasis, can also lead to higher uric acid.
• Medications: Some medications can increase uric acid levels. Examples include certain diuretics (water tablets), low-dose aspirin, and some chemotherapy drugs.
• Genetics: Some individuals may have a genetic predisposition to producing more uric acid or having less efficient kidney excretion.
• Dehydration: Not drinking enough fluids can concentrate uric acid in your blood.

Factors that can lead to lower uric acid levels include:

• Certain medications: Some drugs, like probenecid, are designed to lower uric acid by helping the kidneys excrete more.
• Medical conditions: Conditions affecting the liver or kidneys, or certain genetic disorders like Wilson's disease, can sometimes lead to lower uric acid levels.
• Diet: A diet very low in purines might contribute to lower levels.

It's important to remember that a single high or low reading doesn't always indicate a problem. Your doctor will look at your overall health and may repeat the test or conduct further investigations if needed.

Lifestyle factors that may help

For individuals with elevated uric acid levels, certain lifestyle adjustments can be discussed with your GP as potential ways to help manage them.

• Dietary choices: Focusing on a balanced diet that limits high-purine foods can be beneficial. This might involve reducing intake of red meat, organ meats, and certain types of seafood. Limiting alcohol consumption, especially beer, is also often recommended. Increasing intake of fruits, vegetables, and whole grains is generally encouraged.
• Hydration: Ensuring you drink plenty of fluids, primarily water, throughout the day can help your kidneys flush out uric acid.
• Weight management: If you are overweight, achieving and maintaining a healthy weight through a balanced diet and regular physical activity can help lower uric acid levels. It's generally advised to avoid rapid weight loss or crash diets, as these can sometimes temporarily increase uric acid.
• Regular exercise: Engaging in moderate, regular physical activity is beneficial for overall health and can contribute to weight management, which in turn may help with uric acid levels.

Questions to discuss with your GP

If you have concerns about your uric acid levels, or if they are outside the normal range, it's a good idea to have a conversation with your GP. Here are some questions you might consider discussing:

• What does my uric acid level mean in the context of my overall health?
• Are my uric acid levels high or low enough to be a cause for concern?
• Are there any specific dietary changes you would recommend for me?
• What are the potential long-term implications of my uric acid levels?
• Are there any other tests or investigations that might be helpful?
• What are the next steps in managing my uric acid levels?