Calcium Oxalate Crystals

Reference range:

Kidney stones can be very painful. They can also cause complications like urinary tract infections. But they are often preventable with a few dietary changes.

Where does oxalate come from?

Oxalate comes from many of the foods in our diet. The main dietary sources of oxalate are:

- French fries and baked potatoes

- spinach and other green, leafy vegetables

- rhubarb

- wheat bran

- almonds

- beets

- navy beans

- chocolate

- okra

- nuts and seeds

- soy products

- tea

- strawberries and raspberries

When you eat these foods, your GI tract breaks them down and absorbs the nutrients. The leftover wastes then travel to your kidneys, which remove them into your urine. The waste from broken-down oxalate is called oxalic acid. It can combine with calcium to form calcium oxalate crystals in the urine.

What are the symptoms?

Kidney stones may not cause symptoms until they start to move through your urinary tract. When stones move, the pain can be intense.

The main symptoms of calcium oxalate crystals in the urine are:

- pain in your side and back that can be intense, and may come in waves
- pain when you urinate
- blood in your urine, which can look red, pink, or brown
- cloudy urine
- foul-smelling urine
- an urgent and constant need to urinate
- nausea and vomiting
- fever and chills if you have an infection

What causes calcium oxalate crystals?

Urine contains chemicals that normally prevent oxalate from sticking together and forming crystals. However, if you have too little urine or too much oxalate, it can crystalize and form stones.

Reasons for this include:

- not drinking enough fluids (being dehydrated)
- eating a diet that’s too high in oxalate, protein, or salt

In other cases, an underlying disease causes the crystals to form into stones. You’re more likely to get calcium oxalate stones if you have:

- hyperparathyroidism, or too much parathyroid hormone
- inflammatory bowel disease (IBD), such as ulcerative colitis or Crohn’s disease
- Dent disease, an inherited disorder that damages the kidneys
- gastric bypass surgery for weight loss
- diabetes
- obesity

Potential treatment options:

Small stones may pass on their own without treatment in about four to six weeks. You can help flush out the stone by drinking extra water.

Your doctor can also prescribe an alpha-blocker. These drugs relax your ureter to help the stone pass from your kidney more quickly.

Pain relievers such as ibuprofen and acetaminophen can help relieve your discomfort until the stone passes. 

However, if you’re pregnant, talk with your healthcare provider before taking non-steroidal, anti-inflammatory drugs (ibuprofen, naproxen, aspirin, and celexcoxib).

If the stone is very large or it doesn’t pass on its own, you may need one of these procedures to remove it:

Extracorporeal shock wave lithotripsy (ESWL):

ESWL delivers sound waves from outside your body to break the stone into little pieces. Within a few weeks after ESWL, you should pass the stone pieces in your urine.


In this procedure, your doctor passes a thin scope with a camera on the end through your bladder and into your kidney. Then the stone is either removed in a basket or broken up first with a laser or other tools and then removed. The surgeon may place a thin plastic tube called a stent in the ureter to hold it open and allow urine to drain while you heal.

Percutaneous nephrolithotomy: 

This procedure occurs while you’re asleep and pain-free under general anesthesia. Your surgeon makes a small incision in your back and removes the stone using small instruments.

Possible Prevention:

You can prevent calcium oxalate from forming crystals in your urine and avoid kidney stones by following these tips:

- Drink extra fluids. Some doctors recommend that people who’ve had kidney stones drink 2.6 quarts (2.5 liters) of water each day. Ask your doctor how much fluid is right for you.

- Limit the salt in your diet. A high-sodium diet can increase the amount of calcium in your urine, which can help stones form.

- Watch your protein intake. Protein is essential to a healthy diet, but don’t overdo it. Too much of this nutrient can cause stones to form. Make protein less than 30 percent of your total daily calories.

- Include the right amount of calcium in your diet. Getting too little calcium in your diet can cause oxalate levels to rise. To prevent this, be sure you’re getting the appropriate daily amount of calcium for your age. 

- Cut down on foods that are high in oxalate, like rhubarb, bran, soy, beets, and nuts. When you do eat oxalate-rich foods, have them with something containing calcium, like a glass of milk. This way the oxalate will bind to calcium before it gets to your kidneys, so it won’t crystallize in your urine.



10 000+ happy customers
100% satisfaction
★ ★ ★ ★ ★ customer support

Understand blood, stool, and urine medical results from all your laboratories.

Upload Your Personal Results

Upload Personal Results

For professional account plans go here

for professional account plans go here

Monthly plan

Annual plan

Own it for life

  • Subscription
  • Data entry service included

    Data entry service

    Our exclusive data entry service is a convenient way to get your results into your private dashboard. Simply attach an image or a file of your lab test results, and one of our qualified data entry team members will add the results for you. We support all sorts of files, whether PDFs, JPGs, or Excel. This service is excellent whether you have a lot of reports to upload or are too busy to do the data entry yourself.

  • Instant interpretation
  • Use free data entry form

    Free data entry form

    We strive to make the data entry process easy for you. Whether by offering dozens of templates to choose from that pre-populate the most popular laboratory panels or by giving you instant feedback on the entered values. Our data entry forms are an easy, fast, and convenient way to enter the reports yourself. There is no limit on how many lab reports you can upload.

  • 4000+ biomarkers explained
  • Nutrition recommendations
  • Cancel anytime


$15 /month

billed every month

  • monthly
  • $15 per report
  • ✓ Instant interpretations
  • ✓ 4000+ biomarkers explained
  • ✓ Nutrition recommendations
  • ✓ Free data entry form
  • ✓ Unlimited data
  • ✓ $15 data entry service
  • ✓ Cancel anytime

Most popular

Data entry included


$79 /year

$6.60/month billed annually

  • yearly
  • 5 reports free
  • ✓ Instant interpretations
  • ✓ 4000+ biomarkers explained
  • ✓ Nutrition recommendations
  • ✓ We enter 5 reports for you
  • ✓ Yearly subscription
  • ✓ Cancel anytime

Data entry included


$250 /once

own it for life

  • pay once
  • 10 reports free
  • ✓ Instant interpretations
  • ✓ 4000+ biomarkers explained
  • ✓ Nutrition recommendations
  • ✓ We enter 10 reports for you
  • ✓ No subscription
  • ✓ Dedicated support
  • ✓ Unlimited access

Are You a Health Professional?

Get started with our professional plan

Welcome to Healthmatters Pro.

Save time on interpreting lab results with the largest database of biomarkers online. In-depth research on any test at your fingertips, all stored and tracked in one place. Learn more

Pro Monthly Plus

for health professionals

  • ✓ Track multiple clients results
  • ✓ No setup fees
  • ✓ No hidden costs
  • ✓ Instant interpretations
  • ✓ 4000+ biomarkers explained
  • ✓ Includes data entry service
  • ✓ Personal training and support
  • ✓ Cancel anytime

$75 per month

Use promo code to save 10% off any plan.

We implement proven measures to keep your data safe.

At HealthMatters, we're committed to maintaining the security and confidentiality of your personal information. We've put industry-leading security standards in place to help protect against the loss, misuse, or alteration of the information under our control. We use procedural, physical, and electronic security methods designed to prevent unauthorized people from getting access to this information. Our internal code of conduct adds additional privacy protection. All data is backed up multiple times a day and encrypted using SSL certificates. See our Privacy Policy for more details.