High blood sugar levels affect nearly every part of your body because every part of your body relies on the ingredients in your blood — water, salt, iron, glucose, oxygen, platelets — the list goes on and on!

But high blood sugar levels mean every part of your body is getting far more glucose than it needs. And along with excess sugar, high blood sugar levels can also mean excess acid.

That excess acid is the primary reason that people with diabetes are more likely to develop kidney stones.

What are kidney stones?

Kidney stones — also known as “renal stones” or “uric acid stones” — are hard, small objects that develop from an excess of acid in your urine, according to the National Kidney Foundation (NKF).

Your kidneys are a filter and work continuously to remove different types of waste from your body. When the balance of waste versus water gets out of whack, little crystals start to form from excess chemicals in your urine. 

Sometimes, we pass these smaller crystals through our urine without even knowing. 

When, however, the crystals grow more quickly than your body can manage to pass them, they become too large to pass.

This is when you start becoming aware of common symptoms, including:

• Sudden, intense pain in your lower back
• Pain throughout your torso
• Bloody urine
• Cloudy urine
• Nausea or vomiting
• Fever and chills
• Very strong odor in your urine

If you have some or all of these symptoms, call your healthcare team or visit the nearest urgent care for treatment. 

Types of kidney stones

1. Uric acid — the most common in people with diabetes: This type of stone develops from high levels of acid in your blood and that includes ketone acids from high blood sugar levels. Non-diabetics can develop these, too, and often these stones occur in several family members.
2. Calcium oxalate — the most common in the general population: These form when calcium mixes with oxalate in your urine, but this doesn’t mean you’re getting too much calcium. In fact, it usually means you’re not getting enough calcium (especially from dark, leafy greens) or enough water. Drink more water! Eat more spinach, kale, and romaine!
3. Struvite — common in people with frequent urinary tract infections: As if UTIs aren’t tedious enough, frequent UTIs can lead to struvite kidney stones. The best way to address this is to work with your healthcare team on identifying the cause of your UTIs, and then preventing them from occurring as often.  
4. Cystine — the result of a rare condition called “cystinuria”: These are also commonly genetic, running in the family, and are a direct result of high levels of cystine in your urine. Cystine is an amino acid that builds-up to unhealthy levels, leading to a diagnosis of “cystinuria.” Work with your healthcare team to manage this rare condition.

Let’s take a closer look at the basic symptoms of kidney stones, and the stones most likely in people with diabetes.

Why diabetes increases your risk of kidney stones

The first and most significant reason people with diabetes are more likely to develop kidney stones is that high blood sugar levels make your blood more acidic. That build-up of acid can create crystals, which — if blood sugar levels don’t improve — then form into stones.  

That excess acid disturbs the natural pH balance in your urine, making it the ideal environment for kidney stones to develop.

European Urology researchers determined that people with type 2 diabetes whose A1c levels were over 6.5 percent were 92 percent more likely to develop kidney stones than people without diabetes.

Insulin resistance can also play a factor — which makes sense since people struggle with high levels of insulin resistance are also likely to struggle with higher blood sugar levels. 

“Insulin resistance plays a key role in type 2 diabetes mellitus,” reports research from Reviews in Urology, “and it has been linked to uric acid stone formation. Insulin resistance might result in a deficit in ammonium production in the kidney, which lowers urinary pH, thus generating a favorable milieu for uric acid stone formation.”

If you suspect you’re struggling with kidney stones, you should absolutely talk to your healthcare team about the most effective treatment path — and again, visit the nearest urgent care center if your symptoms are severe.

The number one most helpful thing you can do to prevent future kidney stones is to improve your blood sugar levels. This is easier said than done, of course, but it’s essential for your longterm health, including avoiding kidney stones.