Foods To Avoid For 24-Hour Urine Test

A 24-hour urine test determines what is in your urine and how much urine you produce throughout a 24-hour period. 

The urine test informs your doctor about the health of your kidneys and the mineral balance in your body. 

It is ordered for a variety of reasons. 

Some of the more common reasons for a 24-hour urine test are as follows:

• Chronic kidney disease (CKD)
• Kidney stones
• Other kidney diseases such as polycystic kidney disease (PKD), glomerulonephritis, or nephrotic syndrome
• Structural abnormality to your kidney, such as a cyst
• Bone health
• Low or high urine output
• High blood pressure
• Preeclampsia

You should avoid certain foods before/during the 24-hour urine test in order to improve the accuracy and quality of your test. 

The foods to avoid for a 24-hour urine test vary on what the test is measuring. 

Below we look at what they are.

Foods To Avoid For A 24-Hour Urine Test

A 24-hour urine test is performed to determine what is in your urine and how much urine you produce most of the time. 

Eating and drinking “perfectly” on your 24-hour urine test day is tempting. However, this does not help your medical team in assisting you!  

Depending on the reason for your 24-hour urine test, here are the foods to avoid.

Hydroxyindoleacetic acid (5HIAA)

If your 24-hour urine test will measure hydroxyindoleacetic acid (5HIAA), avoid these foods for three days before the test. 

Avoid these items, as well as any food that contains components of these foods, such as juice, cheese, yogurt, or sauces:

• Bananas
• Pineapples
• Eggplant
• Plums
• Avocados
• Kiwi
• Pecans
• Passionfruit
• Tomatoes
• Walnut
• Plantains

You should also avoid tea, coffee, alcohol, and nicotine before the urine test.

Catecholamines

If the 24-hour urine test will measure catecholamines, it is preferable to avoid alcohol, caffeine, or caffeine-containing beverages three days before the test.

It is also advised to abstain from chocolate, nicotine, and smoke the day before the test.  Refraining from taking drugs for three days before the collection period is also advised.

These foods known to interfere with catecholamine levels should be avoided as much as possible before and during sample collection. 

Emotional and physical stress, as well as severe activity, should be avoided before and during test collection because these can enhance catecholamine secretion.

Aluminum

Avoid eating fruits, juices, and teas for 24 hours before collection. Aluminum-containing antacids can significantly increase urine aluminum production. Avoid taking mineral supplements for 5 days before collection.

Wait at least 96 hours before taking a urine sample if you have been given a gadolinium or iodine-containing contrast medium, as these can alter the test results. 

These media are typically administered to patients prior to an X-ray or CT scan.

VMA

Avoid eating avocado, walnuts, plums, pineapples, caffeine, and tomatoes for at least 24 hours before and during the collection time. 

Do not consume alcohol, coffee, tea, or other caffeine-containing beverages for three days before collection; do not use tobacco or nicotine. 

Additionally, do not consume bananas or citrus fruits, and avoid vigorous exercise.

Serotonin

If you have been scheduled for a 25-hour urine test to measure serotonin levels, you must abstain from the following:

• Bananas
• Avocados
• Tomatoes
• Eggplant
• Plums
• Walnuts
• Hickory nuts
• Coffee
• Pineapple
• Mollusks.

Arsenic

Do not eat any seafood for 48 hours before the urine test. Seafood, which includes shellfish, finfish, and seaweed, is the leading source of arsenic exposure in humans.

Copper

Avoid high-copper diets and mineral supplements for 5 days before collection. 

The following foods are all high in copper:

• Organ meats
• Chocolate
• Mushrooms
• Shellfish
• Wheat bran products
• Whole-grain goods
• Seeds
• Nuts

Uric acid

This test determines the level of uric acid in your urine. Uric acid is a natural waste product of the body. 

It is formed when purines, chemical compounds in food known to cause gout, degrade.  

Foods high in purines include:

• Organ meats
• Some kinds of seafood and fish (including lobster, crab, tuna, and trout)
• Mushrooms
• Dried peas
• Beans

Creatinine

You do not need to abstain from any foods for this test. Ensure your doctor knows all medications, herbs, vitamins, and supplements you are taking. 

This covers over-the-counter medications as well as any illicit substances you may use.

Manganese

Five days before collection, avoid eating manganese-rich foods and mineral supplements. Manganese is found in many foods, including:

• Whole grains
• Oysters
• Clams
• Almonds
• Mussels
• Soybeans and other legumes
• Green vegetables
• Rice
• Tea
• Coffee
• Spices, including black pepper

Before the test, consume these meals in moderation.

Oxalate acid

For at least 48 hours before the collection period, avoid drinking coffee or tea and eating spinach, chocolate, or rhubarb. 

Limit your vitamin C intake (foods or supplements) for 48 hours before and during collection.

Zinc

Avoid taking mineral supplements for 5 days before collection. In rare circumstances, iodine-containing items such as seafood and salt should be avoided for roughly a month before the element testing since they may interfere with the results. 

Fasting samples are also desirable because meals impact zinc levels in the urine.

Mercury

Small levels of mercury found in everyday foods and items may have no effect on test findings.  Avoid eating seafood for 5 days before collection.

Eating high-mercury-content fish and shellfish can elevate your mercury levels. If you have a urine mercury test, you should avoid drinking red wine for 72 hours before the collection.

Histamine

A histamine-free diet must be followed for 24 hours before and during the collection of 24-hour urine. 

You should avoid the following foods:

• Aged bacon
• Beef
• Ham
• Pig
• Sausages
• Silverside
• Cheese
• Frozen fish
• Soy sauce
• Tuna
• Salmon
• Stocks
• Sardines
• Flavor enhancers
• Cauliflower
• Broccoli
• Eggplant
• Olives
• Spinach
• Mushrooms
• Tomatoes
• Gherkin 
• Peanut butter
• Mayonnaise
• Avocados

Calcium

Do not consume alcohol or calcium supplements for 48 hours before beginning urine collection. 

Do light exercise for 24 hours before and following the test. You should avoid milk and other dairy products, such as:

• Yogurt
• Cheese
• Ice cream
• Pudding
• Canned salmon or sardines with soft bones
• Calcium-fortified orange juice
• Ready-to-eat cereals

Citrate

The results of this test are influenced by your diet, which is typically performed while you are on a normal diet. 

A high-carbohydrate diet may raise citric acid levels in the urine. Similarly, vitamin D may interfere with test results.

What Can You Eat During A 24-Hour Urine Test?

Before a 24-hour urine test, you must change your diet and medications. There are no foods to avoid if you are taking a 24-hour urine test for kidney function, kidney stones, or bone health.

Your doctor may instruct you to discontinue specific foods, medications, or supplements depending on the result. This is unique to each person and exam.

Can I Drink Coffee During A 24-Hour Urine Test?

Tea and coffee should be avoided since they serve as natural diuretics, causing you to pass more urine. 

Furthermore, if your doctor has ordered a urine test for metanephrine, you should abstain from caffeine for 24 hours before and during your specimen collection.

How Much Water Should I Drink For 24-Hour Urine Collection?

You will need to drink plenty of fluids during a 24-hour urine collection. Remember, drink at least 8 glasses of water during the 24-hour period.

Can Drinking Too Much Water Before A Urine Test Affect Results?

Yes. Excessive water consumption may result in erroneous results.  This can dilute your urine, making certain components of the 24-hour urine test more challenging to detect.

What Can You Not Do On A 24-Hour Urine Collection?

Things to avoid before a 24-hour urine collection include:

• Exercising vigorously.
• Acute stress.
• Make sure to collect all your urine within the 24-hour period.
• Crossing the 24-hour collection period and collecting an excessive amount of urine.
• The loss of urine from the specimen container due to spillage.
• Failure to keep urine cold when collecting it.

Furthermore, do not mix feces (poop) with pee, or the test will have to be redone. Check that the urine does not freeze before performing tests such as amylase, immunoelectrophoresis, arylsulfatase, pregnanetriol, microalbumin, protein, or uric acid.

What Does A 24-Hour Urine Test Measure?

The components of 24-hour urine tests differ depending on the laboratory.  Many factors will be measured depending on why your doctor ordered the 24-hour urine test. 

Most standard 24-hour analyses include urine volume, oxalate, urine pH level, calcium, citrate, and uric acid concentrations, and supersaturation values.

Calcium oxalate, calcium phosphate, and uric acid supersaturation are all common. Urine potassium, phosphorus, magnesium, ammonium, sulfate, chloride, and nitrogen in the form of urea are also commonly measured.

How To Do A 24-Hour Urine Test

A 24-hour urine sample is used to measure the components of your urine. It necessitates collecting your urine in a particular container for 24 hours.

Preparation

Your healthcare provider will describe the procedure, and you will have the opportunity to ask questions. 

Ensure you understand whether you must avoid particular foods while collecting your urine.

You will be provided huge containers in which to store your urine as well as a container in which to urinate. 

Make sure you understand how to use them. While you’re collecting the urine, keep it in a cool place, for example, in a refrigerator or an ice-filled cooler.

You may be instructed to begin collecting at a specified time. Choose a 24-hour period when you will be at home if feasible to avoid having to transfer your urine.

Inform your healthcare provider if you are pregnant or suspect you are pregnant.

Ensure that your physician is aware of all medications (including prescription and over-the-counter),  vitamins, herbs, and supplements you are taking.

Your healthcare physician may request further specific preparation based on your medical condition.

Before you agree to the test or process, make sure you understand the following:

• The test or procedure’s name.
• The reason for the examination or procedure.
• What to expect and what it all means.
• The test’s or procedure’s risks and advantages.
• What are the potential adverse effects or complications?
• When and where the test or procedure will take place.
• Who will do the test or procedure, and what their qualifications are?
• What would happen if the test or procedure was not available?
• Are there any other tests or procedures to consider?
• When and how will you receive your results?
• Who to contact if you have questions or concerns following the test or procedure?
• How much will the test or procedure cost you?

Things to remember

• Maintain your regular diet, medications, and fluid intake unless otherwise directed by your doctor.
• Do not drink alcoholic beverages.
• This isn’t a competition or a test to see how much urine you can collect in 24 hours.
• A special collection container manufactured by the laboratory is required. It might have a caustic preservative in it. 
• Please do not spill the container’s contents.

Instructions

• Empty your bladder into the toilet when you wake up in the morning. On your container label, write the time and date. This urine should not be included in your timed collection.
• Collect all urine you pass for the remainder of the 24-hour period and immediately place it in the appropriate collection container.
• The test concludes 24 hours after the first (uncollected) specimen was collected the day before. On the container label, write the end time as “Date and Time Completed.”
• Do not extend the collection time if you cannot collect a urine sample at the end of the test.
• Unless otherwise ordered by laboratory workers, the urine container must be refrigerated or stored in a cool place during collection.
• After the collection is complete, return the 24-hour urine container to the laboratory as soon as possible.
• You may be required to have a blood sample collected when you return your container to the laboratory, depending on the test your doctor ordered.

Post-collection

There is no special care required following a 24-hour urine collection. However, depending on your specific case, your healthcare professional may offer additional advice after.

Tips For A Successful 24-Hour Urine Test

A 24-hour urine test is not painful, but it can be annoying! It is not easy to collect all of your urine for 24 hours. 

Here are some tips for passing a 24-hour urine test so you don’t have to redo it!

Make sure that you collect ALL of your urine

Even missing one trip to the restroom can cause the urine test to be less reliable.

Take care not to collect too much urine

Your laboratory will provide you with detailed instructions on when to begin and stop collecting urine. Keep a watchful eye on everything!

Keep your urine cold if required 

Many 24-hour urine tests need you to keep your urine in the refrigerator. Check your directions carefully to check if your urine needs to be kept cold.

Don’t forget to include the preservative

Many 24-hour urine tests include a small vial of powder that helps in obtaining an accurate result. Don’t forget to add it!

Act normally

It’s much easier said than done. Changing your diet or drinking habits can affect your 24-hour urine test results. High stress or unusually strenuous activity can potentially alter the results.

Conclusion

Nobody enjoys completing a 24-hour urine collection. However, it is possible to do it correctly if you follow your healthcare provider’s dietary and collection instructions. 

Following this thorough list of foods to eat and avoid may come in handy because the 24-hour urine test examines the amount of particular components in your pee, such as calcium, salt, oxalate, citrate, magnesium, etc.

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