12 Best Dry and Wet Cat Foods With Low Ash Content

If you’ve ever taken the time to read the ingredients of your cat’s food, you might be a little surprised! Alongside the expected chicken or beef, there is one ingredient that doesn’t seem right: ash! What’s that all about?

Ash is found in most pet food in varying amounts, but this is not a cause for concern. It isn’t literal ash – like what I first thought it was! What you’ll see listed as “crude ash” on the content label of cat food actually refers to the measure of minerals in that food such as magnesium, calcium, and phosphorus.

These are all essential for your cat’s health and can bring benefits to their overall well-being. So, what’s the problem? Well, unfortunately, cat food containing a high content of crude ash provides far more minerals than your cat needs. In fact, it provides more than your cat’s body can handle!

The minerals can block the urethra. This is a dangerous urinary condition that’s best avoided. And thankfully, there are low-ash cat foods on the market that reduce the risk of urinary complications. For cats that are already experiencing issues, these low-ash alternatives are even more essential.

Here you’ll find the best low-ash cat foods currently available. I’ve reviewed a selection of wet and dry options that are delicious, nutritionally balanced, and contain no more minerals than your cat needs. Keep reading for all the reviews and a handy buying guide to help you choose the right product.

My Top Picks

Purina ONE Urinary Tract Health Natural Adult Cat Food (Best Dry Cat Food)

My top pick for dry cat food with low ash content is this product from Purina. It has sufficient protein from real chicken, high moisture for dry food standards, a decent amount of fiber, and it is low in magnesium. My cat also loves the taste, and I’m sure your furry friend will do too!

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Purina Pro Plan Urinary Tract Health FOCUS (Best Wet Cat Food)

My top pick for wet cat food with low ash content is yet another product from Purina. Like their dry low-ash version, it has the best breakdown of protein, fiber, and magnesium. I also love that it has real meat as its protein source – cats prefer eating juicy chunks of chicken, and you know it’s high-quality meat that’s easy on digestion.

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Keep reading for the full review of these two products and more delicious and nutritious cat foods with low ash content. You can also find information on urinary tract issues in cats and further criteria to consider when choosing a diet to improve feline urinary health.

Choosing the Best Low Ash Content Cat Food

Low ash content cat food is usually preferred for cats with urinary tract issues or to reduce the risk of such issues arising. Therefore, my selection of products consists of cat food specifically formulated for urinary care.

I have also evaluated these foods based on the general quality and distribution of their macronutrients, moisture and mineral content, and any extra formulations to support urinary and digestive health in cats. Here is a closer look at each criterion and why they’re of utmost importance:

• High Protein Content: Cats are obligate carnivores, meaning they need meat and protein to supply the essential amino acids needed for survival. All good cat foods provide quality protein. The higher the quality, the richer it is in these essential amino acids.
• Low Magnesium Levels: There is a correlation between cat food high in magnesium and struvite crystal formation. This magnesium enters the urine and can crystalize in the urethra, causing a blockage. All cat foods on this page have extremely low levels of this mineral.
• High Moisture: Proper hydration is key to urinary tract health as an adequate amount of fluid help to dilute urine. Unfortunately, cats are notorious for not drinking enough water, so moisture-rich cat food is a smart way to ensure your kitty is properly hydrated.
• Low in Grains: Grains are found in many commercial cat foods, but they’re not part of a cat’s natural diet. Therefore, they’re harder to digest than protein. I looked for cat foods low in grains to help ease digestion. After all, your cat’s digestive and urinary tracts are closely linked.

Now you know my criteria, carry on and read the reviews below! I have split them into two separate categories: dry cat food and wet cat food. This is purely for the reason that macronutrient percentages of dry and wet food are not suitable for a direct comparison. If you want to know more, you can skip comparing the labels of dry food vs wet food for an explanation of why this is so.

Top 6 Dry Cat Food With Low Ash Content

1. Purina ONE Urinary Tract Health High Protein Natural Adult Dry Cat Food (Best Overall Dry Cat Food)

As mentioned, my favorite low-ash cat food is this product from Purina. This is a dry cat food that is formulated specifically for improved urinary tract health.

Its overall ash content is also low (6.2%) when compared to most dry foods. It has a low magnesium content and decreases the pH level of urine to make it more acidic. Alkaline urine favors the formation of calcium and other mineral deposits, so decreasing pH reduces the chance of a blockage.

The main protein source for this cat food comes from real chicken meat. It doesn’t rely on chicken by-products, so you can rest assured your cat is getting quality, easily digestible, amino acid-rich protein. It also has a high moisture level when compared to most other dry foods to help with hydration.

It is not completely grain-free but has 2% fiber only, which is the ideal amount of fiber that cats should consume daily. This is enough to help soften stools and promote digestion, but not too much that it makes digestion difficult.

Breakdown: Protein: 31% / Moisture:10% / Magnesium: 0.08% / Fiber: 2%

Pros

2. IAMS Proactive Health Adult Urinary Tract Health Dry Cat Food (Best All-Around Health Benefits)

In second place is this dry cat food from IAMS. This is a urinary care dry cat food with its main source of protein being chicken meat mixed with some chicken meal too. Despite the inclusion of chicken meal, real chicken is the first ingredient and so the overall protein quality is great.

This food promotes good urinary healthy by reducing the pH levels in urine. It does this by dropping the magnesium content to just 0.1% and balancing all the other nutrients perfectly. The cat food also has a high moisture level and very sufficient protein content to support strong muscles.

The health benefits don’t stop there either. The kibble is hard and crunchy to improve dental hygiene, the formula contains potassium and calcium for good heart health, vitamin E helps to strengthen the immune system, and your cat’s coat is kept shiny with the optimal amount of Omega 3.

Overall, this is a good quality urinary tract-sensitive dry food that is also quite affordable, and helps tackle lots of other health issues!

Breakdown: Protein 32% / Moisture 10% / Magnesium 0.1% / Fiber 1.7%

Pros

Cons

3. Hill’s Science Diet Dry Cat Food Urinary & Hairball Control (Best Wet Food for Hairball Control)

Does your cat suffer from urinary problems and hairballs? If so, this cat food from Hill’s could be the remedy you’ve been searching for! This is a dry cat food that promotes urinary care as well as weight and hairball control.

The protein in this food comes from real chicken meat and it doesn’t contain chicken by-product meals. You can rest assured that your cat is getting the best, and it tastes so good your kitty will gulp it down! It also is low in magnesium and regulates urinary pH to prevent the formation of mineral deposits and acidic crystals.

The one thing that can be questioned about this food is that it has an excessive amount of fiber because it helps with hairball prevention. High amounts of fiber can be exhaustive on the digestive tract, so if your cat suffers from such issues, you may want to choose another option.

Breakdown: Protein 29.5% / Moisture: 8% / Magnesium: 0.09% / Fiber: 6.5%

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4. Hill’s Prescription Diet c/d Multicare Urinary Care Dry Cat Food (Best Clinically Proven Formula)

Another great low-ash dry cat food from Hill’s is this special urinary formula. It is clinically proven to reduce the symptoms of urinary infections and is designed to help with idiopathic cystitis. So, you know it’s going to do what it says on the tin!

Unfortunately, it does require vet approval because it is a prescription formula. It also isn’t suitable for kittens or pregnant cats because of its mechanism of action: it works to dissolve existing struvite crystals and prevents their formation.

Like all other urinary care-specific foods, it is low in magnesium and controls urinary pH levels. Its main source of protein is real chicken meat, and it also has some chicken by-product meals. The fiber content is also within a good range for healthy digestion and stool formation.

Breakdown: Protein 30% / Moisture: 8% / Magnesium: 0.09% / Fiber: 1.6%

Pros

Cons

5. Hill’s Prescription Diet Weight Urinary Care Chicken Flavor Dry Cat Food (Best for Overweight Cats)

Hill’s has got yet a third low-ash cat food you might consider if trying to improve your cat’s urinary health. It has been clinically proven to improve urinary symptoms by actively dissolving kidney stones and limiting the amount of magnesium ingested.

This dry food is another urinary care-specific formulation that needs vet approval when purchasing.

I would recommend the other Hill’s Pet Prescription diet listed above over this because this one has too much fiber and no real chicken meat for a protein source.

However, this food is better for weight control! Fiber is harder for cats to digest, so it stays inside your cat’s stomach for longer. This means they stay fuller for longer and can help reduce the amount of food they consume. In turn, this calorie reduction leads to weight loss.

Breakdown: Protein: 32% / Moisture: 8% / Magnesium: 0.11% / Fiber: 16%

Pros

Cons

6. Royal Canin Veterinary Diet Urinary SO Dry Cat Food (Best Crystal Prevention)

The last dry cat food on my list of recommendations is this kibble from Royal Canin. This is a urinary care dry food that treats and prevents the formation of struvite crystals in the urine. It achieves this by maintaining low levels of urinary pH and regulating optimal urinary ion concentration.

This food also needs your vet’s approval for purchasing, which is a minor drawback. And unfortunately, although it does have high amounts of protein, this is from chicken by-product meal and chicken fat instead of real chicken meat. The fiber content is also a little higher than I would like to see.

Nevertheless, this does make it great for cats that are a little on the tubby side. The fiber keeps them feeling fuller, so they won’t keep gorging on excess food. On the other hand, cats with chronic kidney disease or heart disease need to steer clear of this cat food.

Breakdown: Protein: 32.5% / Moisture 8% / Magnesium: 0.1% / Fiber 4%

Pros

Top 6 Wet Cat Food With Low Ash Content

1. Purina Pro Plan Urinary Tract Health Gravy Wet Cat Food (Best Overall Wet Cat Food)

If you prefer feeding your cat wet food or a combination of both, this product from Purina is a great option. This is a wet food for urinary care that has real chicken and meat by-products as its protein source.

While it has a very high amount of good protein, it is low in magnesium to help reduce the number of mineral deposits in the urethra. The nutrient profile of the food additionally helps to regulate the pH of urine, ensuring it never gets too acidic or too alkaline.

It has a gravy consistency and cats seem to love it a lot, so you shouldn’t face issues when transitioning to this food. However, you should watch out for weight gain. It’s so scrummy cats can’t get enough of it!

Breakdown: Protein: 12% / Moisture: 78% / Magnesium: 0.022% / Fiber: 0.2%

Pros

Cons

2. Purina ONE Urinary Tract Health High Protein Natural Wet Cat Food (Best Beef Cat Food)

Most cat foods I have recommended so far use chicken as their primary protein source. But if your kitty isn’t a poultry fan, try this wet food from Purina. Its main source of protein is real beef and liver! It contains chicken and poultry by-products too, so your cat is getting all its essential amino acids and more.

Like every product here, this cat food is formulated specifically to improve urinary health and proactively prevent issues from arising. This is thanks to its low magnesium content and its ability to reduce urinary pH.

This food is also free of soy, wheat, and corn, and has an optimal amount of fiber. As a wet food, it is also high in moisture. This makes it aromatic and appealing while ensuring your cat stays hydrated.

Breakdown: Protein: 10% / Moisture: 78% / Magnesium: 0.024% / Fiber: 0.5 %

Pros

Cons

3. Hill’s Prescription Diet Weight + Urinary Care Vegetable & Chicken Stew Canned Cat Food (Best Wet Food for Weight Loss)

This combo cat food from Hill’s tackles urinary health and weight maintenance in one! It is a prescription wet food and so does require approval from a qualified veterinarian, but it is clinically proven to work.

It has real chicken and tuna, as well as pork liver for its protein source. This mix of nutritious proteins ensures your cat gets everything it needs, plus Omega 3 acids, vitamins, and minerals. It also contains whole foods such as carrots and flaxseed.

Overall, this is a good quality veterinary food that actively helps prevent urinary tract problems. This is thanks to its low magnesium content and pH regulating abilities. However, it is high in fiber and not ideal unless you’re trying to get your cat to shift a few pounds.

Breakdown (dry-matter): Protein: 38.2 % / Magnesium: 0.078% / Fiber: 10.8 %

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Cons

4. Hill’s Science Diet Wet Cat Food Urinary & Hairball Control (Best for Hairball Control)

Another option for cats that suffer from frequent hairballs is this product from Hill’s. This is a urinary care wet food that has real chicken as well as pork by-products for protein.

Unfortunately, its protein is not as high when compared to other wet food (the dry matter percentage is 31%). However, it has a high moisture content for dilute urine, a low magnesium content, and helps to regulate urinary pH.

It has also a high level of fiber to prevent hairballs. But while effective at hairball elimination, it can be a strain if your cat has digestive discomfort. This is something to consider, but as another prescription cat food, your vet can advise you on whether or not it’s the right choice.

Breakdown: Protein: 7% / Moisture: 78% / Fiber: 1.5-4%

Pros

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5. Royal Canin Veterinary Diet Urinary SO Morsels in Gravy Canned Cat Food (Best High Protein Option)

Another prescription wet food for urinary care is this canned food from Royal Canin. If you want to feed your cat a high-protein option, this is as high as it gets. Protein accounts for a huge 48% of the total ingredients on a dry matter basis!

Although it has a very high protein content, this protein doesn’t have real meat. Instead, it has pork and chicken by-products and chicken liver as its protein source. Nevertheless, the combination of multiple meat sources still provides a relatively balanced blend of amino acids.

Other than that, it is low in magnesium and actively helps prevent struvite crystal formation. This food also has the highest moisture content on this list and when compared to most wet foods, great for hydration and added taste!

Breakdown: Protein: 8.5% / Moisture: 82.5 % / Fiber: 1.78%

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Cons

6. Purina Pro Plan Veterinary Diets NF Kidney Function Advanced Care (Best Kidney Care Cat Food)

This is a wet food specifically formulated for kidney care! Since the kidneys are an essential part of the urinary tract, I wanted to include this food in my recommendations. It is a solid prescription option for cats that need specific mineral requirements for kidney health.

This cat food is low on phosphorus because this mineral exhausts the kidneys. It has meat and by-products from salmon, liver, and chicken heart as its sources of protein, providing a great blend of amino acids.

Its protein level is not very high, but this is intentional to help improve kidney function. Additionally, it has a delicious pate consistency. This makes it especially suited for cats with dental issues or kittens that are teething.

Breakdown: Protein: 6% / Moisture: 77% / Phosphorus: 0.12% / Fiber: 3%

Pros

Cons

Comparing the Labels of Dry Food vs Wet Food

When comparing the breakdown of nutrients in wet foods and dry foods, we need to be aware that their huge difference in moisture causes their content percentages to appear very different.

When you look at the breakdown of nutrients in my two selections, you might have noticed that most dry foods listed have about 30% protein while the wet foods have about 10%. This might make it seem like dry foods generally have three times more protein than wet foods.

However, this is not a correct inference to make. In fact, wet foods usually have more protein than dry foods. The reason why it appears like this on the label is that since wet food is mostly made up of moisture, there is a lot less dry matter remaining in which the macronutrients reside. When a macronutrient percentage is given, this is for the whole of the food, including its moisture content. That’s why the protein percentage appears lower in wet food.

If you want to compare the macronutrient percentages on wet and dry food labels correctly, you must do so on a dry matter basis.

This means that their moisture content should be extracted from the equation and only the remainder should be compared.

Let’s say we want to compare the protein levels of one wet food and one dry food brand.

We must divide the protein percentage on the label by the percentage of its dry matter (which is 100 minus the percentage of moisture). This will give you the protein percentage of dry matter only. When you do the same with the other food, you’ll get numbers that you can compare directly.

FAQs: Ash Content in Cat Food

Here are some Q&As about ash content in cat food:

Why is There Ash in Cat Food?

I’ve mentioned at the beginning that ash content actually refers to the mineral content in cat food. These minerals include calcium, phosphorus, potassium, sodium, and magnesium, which are all necessary for a balanced and healthy cat diet.

But why do we refer to these minerals as “ash”?

When testing the content of food in a lab, scientists burn a sample of the food to determine its nutritional value. Since all three macronutrients (carbohydrates, fats, and protein) dissolve completely when burned, any ash that remains is the signifier of the food’s mineral content. This is because when burned, minerals don’t vanish completely like macronutrients, but instead, they leave a trace of ash.

Don’t worry, this burnt food is not what you feed your pet. There isn’t actually any literal ash in the food – the “ash” you’ll see on the label is just a term to signify the amount of mineral content.

Which Minerals Make Up the Ash Content in Cat Food?

This may vary with each food, but generally, the minerals that make up the ash content in cat food are sodium, magnesium, phosphorus, calcium, chlorine, iron, zinc, and potassium. Ash is the general term used to refer to the presence of all these minerals.

Good cat food labels will offer you a breakdown of the ash content so that you can see exactly which minerals and how much of each there are in that food.

Why is the Amount of Minerals Important in Cat Food?

Minerals are necessary for your cat, but high levels can have negative effects on your cat’s urinary tract health. Generally, an excess amount of minerals can gather to form crystals in your cat’s bladder and urinary tract. So keeping your cat’s mineral consumption at a healthy level is very important.

Of course, each mineral has a different effect. So instead of choosing food depending on the level of its general ash content, you may need to look out for the levels of separate minerals based on your cat’s needs (with the guidance of your vet.)

Considering each mineral separately proves especially important in cats with kidney issues. Feeding a diet that is low on phosphorus has shown to be beneficial for cats that suffer from kidney issues. On the other hand, the mineral potassium is very important for kidney health. In fact, potassium deficiency may even lead to chronic kidney disease.

So if you opt for a food with low ash content to decrease your cat’s phosphorus intake, you may end up denying her the potassium that her kidneys would benefit from.

Is There a Difference Between Dry and Wet Foods in Terms of Their Ash Content?

Both wet and dry cat food can contain ash of about similar levels.

On labels, it appears as if wet foods have a lower ash content. This is because of the difference in their moisture levels which affects the percentage calculations. So when choosing food for urinary care, opt for dry food that has lower than 8% ash content and wet food with no more than 2%.

If you have a cat with urinary tract issues, you may prefer wet foods over kibble because they have more moisture. Proper hydration is a very effective method in dealing with urinary tract discomfort. If your cat strictly prefers kibble over dry food, then urging her to consume more water daily is another option.

You may also consider mixing dry food and wet food or softening dry cat food to increase its moisture content by adding some broth or water.

Dry foods usually have a higher grain and vegetable content which alters the pH levels of your cat’s urine to make it more alkaline. This may cause struvite crystal formations in the pee. On the other hand, wet foods generally have more protein, which helps regulate the desired level of pH in cat urine.

What is the Appropriate Amount of Ash Content in Cat Food?

Since ash content means mineral content, the question we are really asking is what the appropriate amount of each mineral should be in a healthy cat diet.

Healthy adult cats need about 2% ash content in their daily caloric intake.

Of this, about 0.6% comes from calcium, 0.5% from phosphorus, 1% from potassium, and the remainder is made up of sodium, magnesium, chlorine, iron, zinc, and other trace minerals.

Which Cats Require Low Ash Content in Their Food?

• Cats with urinary tract issues: These cats require low ash content in their food because an excessive amount of minerals (especially magnesium) can build up in their system to cause crystal formation in their urinary tracts.
• Cats with renal problems: Minerals are regulated through the kidneys, so low ash content (especially of phosphorus) in food is generally beneficial for cats with renal issues such as chronic kidney disease, renal infections, etc.
• Senior and geriatric cats: As cats age, so do their kidneys. This means that the efficiency of their kidneys will most likely start to deteriorate. Feeding a low mineral diet to such cats will ease the pressure on their kidneys.

The Best Diet For Cats With Urinary Tract Problems

The most common urinary tract problem in cats associated with high levels of ash is Feline Lower Urinary Tract Disease (FLUTD), which typically causes crystal formation in their bladder and urinary tract.

Crystal formation can be a very dangerous condition if not treated timely. These crystals can be small and inconsequential at first, but they can block the urethra of male cats’ when they are larger. If this becomes the case, a cat may die within 24 hours of the urethral blockage.

This disease is often correlated with high levels of ash in a cat’s diet. However, ash content is not the primary culprit for FLUTD like it was once deemed in the 70s and 80s. Many other factors contribute to FLUTD and crystal formation, most of which you can avoid through a carefully arranged diet for your cat.

Provide a Sufficient Amount of Protein

Crystal formation in cat urine is often due to the increased alkalinity of a cat’s urine. An increase in alkalinity is usually a result of low protein in their food. Healthy cats normally have slightly acidic urine because their diet is very protein-heavy. When the protein level in their diet is not sufficient, their urine becomes more alkaline, which can lead to the formation of crystals in their urinary tract. This is why feeding your cat a high-protein diet is the best way to avoid the formation of struvite crystals in her urine.

With this being said, foods with added meat meals to boost their protein content will also have a higher ash content. This is because meat meals are usually made up of bone and cartilage which have high mineral contents. So, if you are looking to increase your cat’s protein intake, try to avoid an increase in ash content and opt for foods that contain more real meat rather than meat by-products.

You should also keep in mind that some protein sources like salmon or lamb contain more minerals than poultry.

Avoid High Vegetable and Grain Content

High vegetable and grain content in food also cause your cat’s urine to become more alkaline. Generic dry foods have a higher vegetable and grain content than more refined dry foods or wet foods in general. It is therefore quite important to read the nutrition label of cat foods to determine how much of each nutrient your cat is going to be consuming.

Vegetables and grains are high in carbohydrates and good sources of fiber. Although these are nutritious and necessary for cats, carbohydrates should make up only about 2% of an adult cat’s diet. An excessive amount of carbs and fiber will exhaust a cat’s digestive tract because they don’t have all the enzymes to break them down. Too much fiber in a cat’s diet usually causes diarrhea.

Grains are also rich in magnesium, which is the mineral that causes crystal formation in the urinary tract when consumed excessively.

Go for a Well-balanced and Appropriate Amount of Minerals

Apart from the alkalinity of the urine, another cause for crystal formation is a high content of specific minerals like magnesium in your cat’s diet. It is therefore important to keep track of the breakdown of the ash content in your cat’s food.

It is also good to remember that all minerals affect each other and work in close relation to one another.

For example, while maintaining a necessary amount of potassium in your cat’s diet is very beneficial for her kidney and heart health, too much chlorine will cause your cat to lose potassium. Or, even though an excess of magnesium is linked to stone formation in the urinary tract, a calcium deficiency will cause your cat to crave more magnesium. At the same time, an excess amount of phosphorus can hinder the absorption of calcium.

I know it can get quite confusing but most good quality cat foods adhere to these delicate balances so that you don’t have to be extra meticulous about label reading.

But just in case, here’s a general guideline for the daily recommended intake of minerals for healthy adult cats:

• Calcium: 0.18 g
• Phosphorus: 0.16 g
• Magnesium: 25 mg
• Potassium: 0.33 g
• Chlorine: 60 mg
• Sodium: 42 mg
• Iron: 5 mg
• Zinc: 4.6 mg

Encourage Proper Hydration

Proper hydration is the most essential thing that helps prevent urinary tract issues. For this reason, you may choose to opt for wet foods because they have a lot more moisture than dry foods.

If your cat refuses to eat anything other than dry food, you can soften it with vegetable or chicken broth, or mix dry food and wet food.

Make sure to encourage your cat’s consumption of water by always keeping her water bowl full and fresh.

Consult Your Vet About Supplements

Cat foods that are specifically formulated for urinary and digestive tract care often include supplements such as urine acidifiers or whole-foods such as cranberries, blueberries, flaxseed, carrots, pumpkins, etc.

You can consult your vet on supplementing your cat’s food with such ingredients or about administering such supplements separately for increased beneficial effects.

The key here is to have your vet examine your cat closely and to follow your vet’s advice in administering supplements that are specific to your cat’s needs.

CONCLUSION

Whether it is dry or wet, all cat foods have an ash content – in other words, a mineral content. Minerals are important in a cat’s diet, but they have to be in proper amounts and at a delicate balance. Hopefully, I’ve been able to provide you with a basic understanding of the effects some minerals can have especially on the urinary tract of cats.

Low ash content is a very general term and can have a lot of implications. It is always best to regard the complexity of a cat’s specific needs in terms of their diet. Therefore, I’ve tried to provide you with the specific nutrient breakdowns of each food as best I can.

As you’ll have seen, almost all the foods in my two selections are specifically low in magnesium rather than in their ash content as a whole. There are also lots of other factors besides ash content such as protein levels, regulation of urinary pH, and hydration that constitute good urinary tract care for cats.

It is a good idea to keep in mind all these factors, and of course, to consult your vet first when you are considering switching your cat’s diet.