Updated: Aug 7, 2019
By: Lisa A. Pierson, DVM
The information contained in this post is an excerpt from Feeding Your Cat: Know the Basics of Feline Nutrition which can be found at catinfo.org.
Diet is the brick and mortar of health. This paper lays out some often-ignored principles of feline nutrition and explains why cats have a better chance at optimal health if they are fed a quality canned food diet instead of dry kibble. Putting a little thought into what you feed your cat(s) can pay big dividends over their lifetime and very possibly help them avoid serious, painful and costly illnesses. An increasing number of American Veterinary Medical Association members, including board-certified veterinary practitioners, are now strongly recommending the feeding of canned food instead of dry kibble.
The three key negative issues associated with dry food are:
1) type of protein - too high in plant-based versus animal-based proteins
2) carbohydrate load is too high
3) water content is too low
Keep in mind that the best time to implement a diet change is when the cat is healthy. Trying to get an ill cat to embrace a new type of food can be problematic and a cat that is not feeling well may even develop a food aversion if they associate the new food with their discomfort.
Sick cats are often not consuming enough calories as it is so if your cat has a decreased appetite due to illness, this is not the time to push a diet change with too much intensity.
For patients with urinary tract problems, it is extremely important for them to increase their water intake. However, because cystitis (inflammation of the bladder wall) is thought to be linked to stress – and implementing a diet change can be stressful - we need to be mindful of this and go slowly.
While you are working toward getting your cat to eat canned food, you can increase their water intake by using flavored waters such as tuna water, beef or chicken broth, clam juice, lactose-free cat milk, etc. You can make you own tuna water by adding 3 cups of water to a can of tuna. Mash it up and let it sit for ~15 minutes then pour the water into covered (to help maintain freshness) ice cube trays. 3 cups of water will fill two 16-cube trays. The ice cube trays can be used for other flavored liquids as well.
Prior to using, heat the ice cubes to ‘mouse body’ temperature and then add 1-2 TBS per meal of canned food in addition to putting some in a bowl as a separate drink of water.
For diabetic patients, it is very important to decrease their carbohydrate consumption (to less than 7-10% of their daily caloric intake) while keeping in mind that as dietary carbohydrates are lowered so will the insulin needs for nearly all cats. If this fact is not considered – with the insulin lowered accordingly - a dangerous hypoglycemic (low blood sugar) state may occur. This issue is discussed in more detail at catinfo.org – Feline Diabetes – under the ‘STOP sign’ section and should also be discussed with your veterinarian. It is critical for diabetic patients to consume enough total calories per day to help prevent the onset of diabetic ketoacidosis (DKA). This does presents a more challenging situation when implementing a diet change for these patients, but not an impossible one.
On a good note, one of the side effects of diabetes is increased hunger because the body is ‘starving internally’. This negative issue can actually work to our benefit because it may make the patient more inclined to try a new food but, again, monitoring total daily caloric intake is critical when transitioning a diabetic cat to any new diet.
Please understand that I am not saying that you should refrain from introducing canned food into a sick cat’s world - because they may even surprise you by favoring canned over dry - but go forward with the above comments in mind while making sure that your cat is consuming enough calories as discussed below.
Vacations and jobs that demand long working hours are often used as reasons for free-feeding dry food to cats. However, these situations have a very simple remedy.
With regard to vacations and pet-sitters, cats need to be checked on at least once each day to clean their litter box and to make sure that all is well.
Let’s say that you are going to be gone for 1 week. Freeze 7 meals and have your once-a-day pet-sitter put out two meals at each visit – one meal that is at ‘mouse body’ temperature and one that is frozen. The freshness of the frozen meal will be prolonged and your cat will be fine until your pet-sitter returns.
The same trick can be used if you are working long hours or if you live in a particularly hot climate and want to leave food out for many hours.
There are few things in life more frustrating than dealing with a finicky cat. The members of this species can be incredibly ‘set in their ways’ when it comes to their dietary preferences. Cats, like children, often resist what is best for them. The two most frequent comments that I hear from people when trying to convince them to feed their cats a healthier diet are "my cat won't eat canned food" and "but my cat really likes his dry food." Children really like potato chips and ice cream but that certainly does not mean those food items constitute optimal nutrition.
The transition process often involves much more than just plunking down a new food item. Time, patience, and tricks are often required.
One reason that cats like dry food so much is because the pet food companies do not play fair when manufacturing this sub-optimal food source. They coat the kibble with extremely enticing animal digest sprays which are very pleasing to a cat - making a poor quality diet very desirable to the target animal.
In addition to the aforementioned coating of dry food with animal digests, another issue is one of a crunchy texture which is very different from canned food. Cats are very resistant to such a drastic change in the texture of their food.
If you are convinced that getting your cat off of dry food is the way to go, read on for some tips on how to accomplish this.
The key is to do it slowly and with patience and incorporate various tricks for the stubborn cats. The most important issue is actually making the change, not how fast you accomplish it. I must say that my cats tested every ounce of patience I had over a 3 + month period of time during their transition from dry to canned food. They had been on dry food their entire lives and did not recognize canned food as food. My cats ranged in age from 2 years to 10 years at the time of the transition.
The single biggest mistake I see people make time and again is to say that their cat "won't touch" the new food and then panic and fill up the bowl with dry food. In many cases, it is simply not that easy to get cats off of dry food! So, roll up your sleeves and be prepared to patiently out-stubborn your cat. (See Molly's story at catinfo.org – Feline Obesity page - for a look at one very stubborn cat.)
There are two categories of cats - those that will eat canned food and those that will be extremely resistant to eating anything other than dry food. If your cat falls into the first category, lucky you. These cats will take to it with the attitude of “finally – an appropriate diet for my species.” In this case, if your cat has been on all dry food, or only receives canned food as an occasional 'treat', start by feeding canned food in increasing amounts. Gradually decrease the dry, taking about a week to fully switch the cat over to 100 percent canned food.
Note: Truth be told, I have switched many cats from a 100% dry food diet to 100% canned food ‘cold turkey’ without any problems at all. That said, it never hurts to be more cautious by going slower.
Some cats may experience softer stools during the transition. I do not worry if this happens and tend to 'ride it out'. If diarrhea results from the diet change you will either need to experiment with different canned foods or slow the transition down and do it over a period of several weeks.
When cats develop diarrhea during a diet change, many people run back to dry food and abandon the transition. However, that this is not a good answer. I have never encountered a cat that ‘needed’ dry food for intestinal health. There has always been a healthier dietary solution.
Another complaint that I often hear is that cats often regurgitate their canned food shortly after ingesting it. I confess that in the otherwise-healthy cat, I do not understand why cats do this. However, it is not an uncommon complaint and I urge people to stay the course if the cat seems to be healthy otherwise. One of my own cats did this a few times per week for many weeks after the transition – and then she stopped doing it. I tried to tell her how expensive the food was – and to please stop doing that, especially on carpet - but she ignored me.
The average cat should eat 4-6 ounces of canned food per day split between 2-3 meals but this is just a general guideline. When determining how much you should be feeding your cat once transitioned to canned food, keep it simple. Too fat? Feed less. Too thin? Feed more.
Some cats are very easy to transition to canned food simply by gradually mixing increasing amounts of canned food in with their dry. However, many cats won’t fall for this trick.
Now....for the stubborn cats......
If you are unlucky like I was, and your cat does not recognize the fact that he is a carnivore and would live a healthier life if eating canned food, (or a properly balanced home-prepared diet) then you will have some work to do. Some cats that have been on dry food for their entire life will be quite resistant to the diet change and may take several weeks or longer to make the transition to a healthier diet – so be prepared to be frustrated…..patient…..and more stubborn than your cat!
For 'resistant-to-change' cats, you will need to use the normal sensation of hunger to help with the transition. For this reason, it is very important to stop free-feeding dry food. This is the first, and very critical, step. You need to establish set mealtimes. They are not going to try anything new if their bowl of dry food is in front of them 24/7.
Cats do not need food available at all times. It really is okay for them to experience a hunger pain! That said, it was very hard for me to listen to my cats begging for food even though I was strong in my conviction that I was heading them in the best direction for optimal health. It truly was a stressful time for me and them. Actually, I think it was harder on me! This is where many people fail and just give in and fill up the dry food bowl. There were a few times when I had to call my 'sponsor' and was instructed to "just leave the house if you can't take looking into those eyes!" I left the house. Those pitiful little cries of "I have not had food for two WHOLE hours!" were hard to take. But, lo and behold, they were just fine when I returned. Not one cat had died from hunger.
On the other hand, do not attempt to withhold food for long periods of time (greater than 24 hours) with the hope that your cat will choose the new food. You need to ‘convince’ them that a high quality canned food really is good for them, rather than to try starving them into it - which does not work anyway. Allowing a cat to go without food - especially an overweight cat - for a long period of time (greater than 48 hours) can be quite dangerous and may result in hepatic lipidosis (fatty liver disease).
Hepatic lipidosis can also develop when a cat consumes ~50% or less of his daily caloric requirements over a period of many days. The definition of "many" varies from cat-to-cat. For this reason it is important to understand that you need to have some idea of the calories from canned food combined with the calories from dry food that your cat is consuming on a daily basis while you are implementing the transition to canned food. Or, if you have a multiple-cat household that makes it difficult to know how much each cat is consuming, I suggest weighing the transitioning cat daily.
I have never seen a cat develop hepatic lipidosis when consuming at least 15 calories per pound per day. This number is figured on lean body weight, not fat weight.
If your cat weighs 18 pounds but really should weigh 12 pounds, please make sure that he is consuming at least ~180 calories per day. (12 pounds lean body mass X 15 calories/pound/day = ~180 calories/day)
If you have a small female cat that should only weigh 9 pounds, please make sure that she is consuming at least 135 calories per day.
Canned foods never list the calorie content on the can but many dry foods do list this information on the bag. A rough guideline for the calorie content of most canned foods that are 78% moisture is ~30 calories/ounce but can range from 20 to 40 calories/ounce as shown by the chart located at binkyspage.tripod.com/canfood.html.
Most cats will lose some weight during the transition to canned food. Given that a very high percentage of cats are overweight to begin with, this is a favorable result of the diet change - as long as they do not lose too much weight too fast! A cat should never lose more than 1-2% of his body weight per week - preferably closer to 1%.
I highly suggest that all cat caregivers weigh their cats periodically – daily if you are not able to monitor their caloric intake as mentioned above. This will help ensure a safe transition to a healthier diet and, in general, weight loss is often the first sign of ill health for any reason. I make it a point to weigh my cats at least twice yearly.
The Health-O-Meter HDC100-01 baby scale weighs to the nearest 1/2 ounce and has a 'hold' button on it that helps obtain an accurate weight even for a cat that is moving around a bit.
All of my cats lost weight during the three months that it took to switch them to canned but none of them became too thin or lost weight too fast. They slimmed down to a nice lean body weight – losing fat while maintaining their muscle mass. They also became much more active.
If your cat is overweight, please see the Feline Obesity page at catinfo.org.
Resign yourself to the fact that you will be very frustrated at times and you will be wasting canned food as they turn up their nose at it. Also, you may want to immediately switch your cat to a dry food that has fewer calories from carbohydrates than most dry foods – especially if you are dealing with a diabetic cat. There are three grain-free/low carbohydrate dry foods currently on the market: Natura/Innova's EVO, Wellness CORE, and Nature's Variety Instinct.
These low-carb dry foods are very high in fat and therefore are very calorie dense. These foods must be portion-controlled otherwise your cat may end up gaining weight. Note that dry Innova EVO has 612 calories per cup according to the information on the bag. This is substantially higher than most dry foods.
One quarter of a cup contains 153 calories so be very careful to pay attention to how much of these high calorie dry foods you feed.
The caloric needs of an average cat can range between 150 - 250 calories/day depending on their lean body weight and activity level.
The low-carb dry foods are also very high in phosphorus. This is especially detrimental for cats with compromised kidney function.
And, of course, these low-carb dry foods are water-depleted - just like all dry foods - are and are cooked at very high temperatures in order to dry them out.
I do not recommend these dry foods for long-term feeding for all of the reasons stated above. Please use them only as transition diets.
Be sure to stay away from any "light" varieties since those types of foods are very high in carbohydrates.
Here are some various tricks for the stubborn dry food addicts. Keep in mind that different tricks work on different cats:
• If your cat has been eating dry food on a free-choice basis, take up the food and establish a schedule of two - three times per day feedings. I really do prefer just twice-daily feedings when trying to transition them. A normal, healthy hunger response after 12 hours goes a long way to convince them to try something new.
Once the cat has transitioned to canned food, I prefer to either free-feed them (if they are not too fat) or to put out a meal three times per day. Small cats in the wild eat 8-10 small meals per day. I do not worry about leaving canned food out for up to 12 hours at a time. Keep in mind that a lion is not going to eat his entire prey immediately.
If you want to take the transition very slowly, you can feed the amount that your cat normally consumes in a 24 hour period - split up into two feedings to get him used to meal feeding. Many people, however, are unsure as to how much their free-fed cat really eats so I would start off by figuring out the calories that your cat needs to maintain his weight - if he does not need to lose any weight – and then divide that in half for the AM and PM feedings.
Again, most cats only need 150-250 calories/day. This means that, roughly, the AM and PM feedings should be about 100 calories each. The dry food bag should tell you how many calories are in a cup of food but if it does not, you can check to see if it is listed on the dry food chart at binkyspage.tripod.com/dryfood.html
Leave the dry food down for 20 - 30 minutes, and then remove any uneaten portion. Repeat in 8 -12 hours depending on if you are feeding 2 or 3 times per day. During the first few days of transitioning to a set schedule, you can offer canned food during the dry food meals, or in-between meals. The stubborn ones, however, will not touch it. Do not despair - all cats will eventually eat canned food if their caregiver is determined, methodical, and patient enough. Once your cat is on a schedule you will notice that he is more enthusiastic about food during his proper mealtimes and will be much more inclined to try something new.
• Once you have established scheduled mealtimes, you will most likely need to start feeding a bit less at each mealtime in order to get the normal sensation of hunger to work in your favor. Again, we are trying to use the normal sensation of hunger to help us out. We are not trying to starve the cat into the diet change.
• Once your cat is on a schedule of meal-feeding instead of free-feeding, try feeding a meal of canned food only. If he will not eat it - and the very stubborn ones won't - try not to get frustrated - and do not put down dry food. Try some of the other tips listed below. If he still will not eat the canned food, let him get a bit hungrier. Offer the canned again in a couple of hours – or just leave it out. Some cats will be more apt to try something new if they keep walking by it and seeing/smelling it. Try a different brand/flavor or a different 'trick'. Once it has been ~18 hours since he has eaten anything, give him just a small amount (~1/4 of a cup - or less if it is EVO) of his dry food – keeping track of his daily calorie intake.
• Remember to be patient. You do not have to accomplish this in a day…or a week…or even in a month.
• Exercising your cat with a tassel toy before feeding can also help stimulate his appetite.
• Instead of putting the dry food portion in his bowl, turn it into a game. Throw the dry food, one or two pieces at a time across the room so that he has to run back and forth and ‘hunt’ for it. This trick worked very well for my obesity project, Bennie. Bennie went from 30 lbs to 18 lbs once on portioncontrolled canned food. I used 25 pieces/day of EVO for him to run after which was about 25 calories. EVO is very calorie-dense so 25 pieces of most dry foods will not contain this many calories.
Playing the ‘toss the dry food portion’ game will help your cat burn off calories and should stimulate his appetite so that he may be more inclined to try canned food. It is also a great way to interact with your cat which helps to relieve the stress/boredom that many indoor cats experience.
• Cats' noses are much more sensitive than ours are. They can smell the dry food in the cupboards. I suggest putting it in the refrigerator (preferable to keep the fats from getting rancid) or at least putting it in a tightly sealed container. If they can smell it, they will hold out for it. Some people recommend getting it out of your house completely, but this is not possible when you are dealing with a very stubborn cat that needs a bit of time and patience to make the transition happen.
• Pet your cat while he is in front of the food bowl. Some cats will be stimulated to eat when being petted.
• The following worked for my cats: Sprinkle a very small amount of tuna – or any other favorite treat (some cats do not like fish and would prefer cooked chicken) - on the top of the canned food and then once they are eating this, start pressing it into the top of the new food. (The “light” tuna is better than the fancy white tuna because it has a stronger smell. Or, Trader Joe’s makes a Cat Tuna that is very stinky.) Be careful to decrease the amount of fish as soon as possible. Health problems can occur with a predominantly fish-based diet. Plus, you do not want to create a situation where your cat will only eat very fishy foods.
• Make sure that any refrigerated canned food is warmed up a bit. Cats prefer their food at 'mouse body’ temperature.
• Try offering some cooked (or raw – whole meats, rinsed well or parboiled) chicken or meat baby food or deli-meat (‘cold-cuts’). One of the goals is to get your cat used to eating food that does not crunch. He needs to get used to a different texture. Also, chicken is a great source of protein to point him in the proper direction toward a high protein, low carbohydrate diet. If he eats the chicken, he may head right into eating canned food. Then again....he may not.
• Try sprinkling some parmesan cheese on the canned food. Most cats love parmesan cheese and this trick has been very successful for me.
• Try a product called FortiFlora. This product can be obtained from your veterinarian or online. Most cats love FortiFlora and this has recently become my favorite trick. This is a probiotic made by Purina but you are not going to use it for its probiotic properties. You are just going to use it as a flavor enhancer. The base ingredient in FortiFlora is animal digest - the very substance that makes dry food so very enticing to cats. The directions say to use 1 package/day - and you can use this much if you want to - but this amount is not usually necessary. You may only need ~1/4 of a package - or less - with part mixed into the food and part sprinkled on top of the food just as you would use salt and pepper on your own food. I also have no worries about using this product past the expiration date.
• There are numerous freeze dried meat treats on the market that you can also sprinkle on top of the canned food. Halo's Liv A Littles is a popular choice.
• Speaking of texture, a common question is "can I just soak the dry food in water?" I hedge more than just a bit at this question. Dry food often has a high bacterial content. Mold is also often found in dry food. There have been many deaths of dogs and cats secondary to eating mold mycotoxins, vomitoxins and aflatoxins which often contaminate the grains found in dry food. If you want to try the trick of wetting down the dry food to alter the texture, please leave it out for only 20-30 minutes then discard it. Bacteria and mold thrive in moisture.
• Try dipping some dry food pieces in the juice from the canned food. Some cats may refuse to eat it if the dry food even touches the canned food. But if he will eat it with a bit of canned juice on it, try the 'chip and dip' trick. Scoop up a tiny bit of canned food onto the piece of dry food. Put them on a separate plate from his small portion of dry food. Some cats will eat their small portion of dry and then go investigate the dry food with a tiny bit of canned on it.
• Going one step further, try adding a few small pieces (the size of an eraser head) of the canned food to the portion of dry food. Your cat may pick around the canned food but will get used to the smell - and texture - even if he does not eat any pieces of the new food.
• Crush some dry food and sprinkle it on the top of the canned food.
• If you do not think it will upset your cat, try gently rubbing a bit of canned food or juice on the cat's gums. This may get him interested in the taste and texture of the new food - but do it gently. You do not want to make this a stressful situation and create a food aversion. (This trick is commonly used to get just-weaned kittens used to eating canned food.)
• If you do not think it will upset your cat, use your finger to put a tiny bit of canned food or juice on his paw for him to lick off. This has not worked for me in the two cats I have tried it on but it is another idea. Make sure you do it without stressing your cat. Again, you do not want to create a food aversion.
• If you have a multiple cat household, some cats like to eat alone in a less stressful environment, so you may need to take these cats into a separate, quiet room to think about the error of their ways - their carbohydrate/dry food addiction. Once in a quiet setting, away from the other cats, two of my cats would eat canned food/tuna ‘meatballs’ by hand. Not from a bowl, mind you, but only from my hand. I’m not sure who was being trained. They did eventually start eating from a bowl after a few hand feedings.
• Try various brands and flavors of canned foods. Try Friskies, 9-Lives, Fancy Feast, etc. Many cats love the foods that are all by-products and turn up their noses at the ‘higher end’ foods like Merrick, Wellness, Nature’s Variety, etc. You can worry about feeding a higher quality canned food later and you can always mix different types of food together. The initial goal is just to get your cat used to eating canned food and not dry kibble. And keep in mind that it is better to feed Friskies or 9-Lives canned food than any dry food because, even though they are made up of by-products, they have the Big Three covered: 1) high in water, 2) usually low in carbohydrates, 3) animal-based proteins – not plant-based.
• Syringe-feeding is also another option but has to be done with finesse and patience so as to avoid a food aversion. If you choose to syringe-feed, your goal is not to feed him a full meal. Sometimes just syringing a 1-2 cc's can 'jump-start' your cat’s into eating the canned food - maybe not the first time but it will at least get him to taste the new food and experience a foreign texture. The best way to syringe- feed is to kneel on the floor with your cat between your legs so he is facing the same way as you are. Then, using a small (1cc/TB) syringe, slip it in the side of his mouth and give about 1/2 cc at a time. You don’t want to overwhelm him with too much in his mouth. He may spit it out but you are just trying to get him used to the taste and texture, not stress him.
Few canned foods will make it through the tip of a syringe but human meat baby food works well for this trick. You can also water it down a bit if you need to. Even though human baby food is not a balanced diet for long-term use, it is a great tool that can be used to help transition a cat to a texture that he is not used to.
If you want to use canned cat food instead of baby food, you can ask your vet for a canned food that is designed to be syringe-fed. Or, if using commercial canned food, you will need to cut off the end of the syringe so that the opening is as big as the barrel. Make sure that the tip is smooth. If you do not want to cut the tip of the syringe off, you will need to puree a pate (versus chunks) type of food. I puree Wellness for this. I run it through the blender with a small amount of water (~3-4 tablespoons/5.5 ounce can). Then I strain it to remove anything big enough to clog the small tip of the syringe.
• I did have to take drastic measures for a foster cat named Molly. She was dangerously obese (20 lbs - double what she should have weighed) and would not eat canned food even after two weeks of syringe-feeding her. She needed to go in for a dental so while she was under general anesthesia, I put in a feeding tube that I could use for easy delivery of canned food. This took the stress off of both of us. After two weeks of feeding her via the tube she started licking the canned food from my fingers then suddenly decided it was time to eat it. That was a few years ago and she is now a playful, animated cat. Before the weight loss of 7 lbs, she could barely walk, could not clean herself, and was quite possibly headed for diabetes and arthritis.
• Don't give up. One of my barn cats ate dry food for the first 12 years of her life. She would never touch the canned food that the other cats ate. Then, one day, she found her 'inner carnivore' and started eating canned food out of the blue! I was shocked. That was 4 years ago and she has been on a 100% canned food diet since she made the switch. These are just a few tricks that you can try. Different tricks work on different cats. The key is to be patient. Remember, it took me three months to get my cats on 100% canned food. Most cats, however, will not take this long.