Urinary Crystals in Cats: What You Need to Know and How Nutrition Can Help

“Cats can work out mathematically the exact place to sit that will cause the most inconvenience.” – Pam Brown, Poet

Urinary crystals are common in cats. Urinary crystals are microscopic crystals that form in your cat’s urine. These crystals irritate the bladder wall and can lead to a bladder infection. These crystals can also clump together and form bladder stones. In male cats, urine crystals can clump together into a kind of plug that can get stuck in the urethra, leading to a life-threatening blockage.

How do urinary crystals develop?

Urinary crystals are caused by a complex interplay of:

• Urine pH: The acidity of the urine determines what type of crystals form. An alkaline (high pH) urine promotes struvite formation, while an acidic (low pH) urine stimulates calcium oxalate formation.
• Nutrition: There are several factors in the diet that play a role in the development of bladder crystals. For example, an imbalance in minerals such as magnesium, calcium and phosphorus in the diet can contribute to crystal formation. Nutrition also has a major impact on the pH of the urine.
• Low fluid intake: If your cat doesn’t get enough water, the urine becomes more concentrated, which increases the risk of crystal formation.
• Stress: Stress can lead to changes in urination behavior, which causes urine to stay in the bladder longer. This promotes crystal formation.
• Overweight: Overweight cats are more likely to suffer from urinary tract problems, including bladder stones.

Complaints in Cats with Urinary Crystals

If a cat has urinary cystals, the following symptoms may occur:

• Difficulty urinating: The cat often sits in the urination position, but there is little or no urine.
• Pain or discomfort during urination: Your cat may meow plaintively or show visible stress.
• Blood in the urine (hematuria): You may notice a pink or red tint in the urine.
• Excessive licking of the genitals: This may indicate pain or irritation.
• Peeing outside the box: Bladder problems often cause uncleanliness.
• Lethargy or loss of appetite: In severe cases, such as a blockage, the cat quickly becomes ill.

How do we determine bladder crystals?

The veterinarian can diagnose bladder crystals by:

• Urinalysis: An analysis of the urine can reveal the pH, crystals, blood, and any infections.
• X-ray or ultrasound: This can be used to detect bladder stones.
• Physical: The vet will check if the bladder is full and causing pain.

The two most common types of bladder crystals in cats

In cats, the two most common types of urinary crystals are:

• Struvite (magnesium-ammonium-phosphate)
• Calcium oxalate

Each type requires a different approach, particularly when it comes to nutrition.

Struvite Urinary Crystals

Struvite consists of magnesium, ammonium and phosphate and usually forms in an alkaline urine (pH > 7). It is the most common form of bladder stones in cats and is often treatable with food.

The nutritional approach to struvite

• Lowering urine to pH <6.5: The diet has a major impact on the pH of the urine. By adjusting the feeding, we can influence the pH.
• Magnesium and phosphorus: An excessive amount of these minerals in the diet increases the risk of struvite.
• To increase fluid intake: Food with more water, such as fresh food or canned food, increases fluid absorption and reduces the risk of struvite.

Feeding Options for Cats with Struvite

Fortunately, for cats that are sensitive to struvite, there are multiple food options available to regulate urine pH and prevent crystal formation:

• Kibble and canned food: Special dietary foods are available through the veterinarian, both in kibble and in wet food. These are formulated in such a way that they make the urine more acidic (pH <6.5) and limit the amounts of magnesium, phosphorus and ammonium. Wet food is preferred because it increases fluid intake, which is important for diluting urine.
• Raw meat food (BARF or KVV): There are various raw meat foods available that are suitable for cats that are sensitive to struvite.
• Tailor-made fresh food: For the most individual approach, you can opt for a freshly prepared diet that is fully customized by a veterinary nutritionist. This is an excellent choice if your cat has specific needs, such as allergies, other health issues, or if you want complete control over the ingredients.

With all these options, it is important to make the right choice for your cat. As an integrative veterinarian, I am happy to help you determine which food best suits your cat’s unique needs. Together we look at his health, preferences and what is practically feasible for you. The goal? A happy, healthy cat with no bladder problems!

Calcium oxalate crystals

Calcium oxalate is formed from calcium and oxalates in an acidic urine (pH <6.5). This form of grit is more difficult to influence with food than struvite. Once stones have formed, they can no longer be dissolved with food and surgical removal of the stones is often necessary.

Nutrition does play an important role in preventing calcium oxalate.

Nutritional approach:

• Keeping urine pH neutral (6.2-6.8): This prevents the urine from becoming too acidic and promotes the formation of calcium oxalate crystals.
• Limiting oxalates: Avoid foods rich in oxalates, such as spinach and rhubarb.
• Regulating calcium intake: A balanced calcium intake is essential; An excess or deficiency can increase the risk of calcium oxalate. Some cats with calcium oxalate have too high a calcium level in the blood. It is important to check this.
• Magnesium and phosphorus: Regulating the amounts of these minerals in the diet.
• To increase fluid intake: Hydration is very important with this form of grit to dilute the urine and prevent crystal formation.

Feeding Options for Cats with Calcium Oxalate

For cats that are sensitive to calcium oxalate grit or stones, it is important to choose the food carefully. Unfortunately, calcium oxalate stones do not dissolve through diet, so the focus is entirely on prevention.

• Kibble and canned food: There are special dietary foods available that indicate that they are suitable for the prevention of calcium oxalate stones. This food focuses on maintaining a neutral urine pH (between 6.5 and 6.8) and limiting oxalates and calcium. Although these diets can be useful, in practice they are not always effective. That’s why it’s important to check the urine regularly (for example, via urine pH strips or at the vet) to see if the food is actually working for your cat.
• Raw meat food (BARF or KVV): There is a raw food that can be used in cats with calcium oxalate. As with the kibble and cans, it does not always work very well and it is important to check the efficacy of the food through urine and blood tests.
• Tailor-made fresh food: In my experience, tailor-made fresh food offers the best results in cats with calcium oxalate problems. With a fresh diet, we can tailor the diet to your cat’s specific needs, including blood values and urinalysis. This approach requires expertise, but often offers the best results. This is what I do regularly and what I see good results with. By combining a tailor-made diet with regular check-ups, we help your cat to live comfortably and minimize the chance of new calcium oxalate formation.

Conclusion: Nutrition as a Key Factor

Bladder crystals in cats can cause serious health problems, but with the right diet, you can prevent many problems. Whether it’s struvite or calcium oxalate, hydration, urine pH, and mineral balance are crucial.

As an integrative veterinarian , I help cats like yours stay healthy and happy, even with challenging issues like bladder stones. My approach is personal and scientifically based. This means that I will work with you to look at the specific needs of your cat and make a tailor-made plan.

Whether you choose commercial food or want to cook for yourself, I will help you find the right balance and prevent or control bladder stones.

Do you have a cat with crystals or do you just want to make sure you’re making the best choices for its health? Please feel free to contact me. Together we ensure that your cat can live a comfortable, healthy and long life!