Finicky cat with food choicesCats are what we call “obligate carnivores” – they have evolved to eat a diet primarily of animal meat. They have small stomachs, short intestinal tracts, and are designed to eat frequently.  A feral cat eats eats the equivalent of 6-8 mice as he hunts from dusk to dawn. In addition to small rodents, reptiles, birds, insects, and rabbits are also on the menu. He consumes the entire prey, including the blood, hair, skin, bones, tendons, and gut contents. These prey are high in protein, have some fat, but little carbohydrate. A feral cat gets about 52% of his energy from protein and 46% from the fat of the prey he eats.

This post is the first in a series that aims to highlight things you need to know when feeding your cat.

Three things to know when feeding your cat

Essential Amino Acids

Amino acids are the building blocks of proteins, those molecules that are used to build and repair tissues and act as hormones or enzymes, among other roles.
Amino acids not synthesized in the body are called essential amino acids and must be consumed in the diet. The 9 essential amino acids required by most mammals are: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine. (Reference 1)

Cats must consume two additional amino acids: arginine and taurine. (Reference 1)

  • Taurine (for vision, cardiac muscle function and the function of nervous, reproductive and immune systems). Sources are meat, poultry (in particular the heart) and fish.
  • Arginine (for making proteins, stimulating the release of growth hormone and insulin, helps eliminate ammonia from the body).  Sources are animal tissue.

#1. These 11 essential amino acids will be supplemented in cat foods that are formulated according to the AAFCO feeding guidelines.

Feeding Your Cat – Can Cats Digest Carbohydrates?

Cats in the wild eat a diet high in protein and fat, with little carbohydrate.  Carbohydrates (grains, corn, potatoes, legumes) are needed to make dry commercial pet foods. Carbohydrates are combined with other nutrients to make a “dough” that is formed into kibble and cooked.  These foods certainly are convenient and many cats like them, but can they digest the carbohydrates in these foods?


Dietary carbohydrate provides glucose to the cells for most species including humans. If there is not enough dietary carbohydrate, proteins can be used as a glucose source via the process of gluconeogenesis. Gluconeogenesis occurs in the liver and is activated for most species during fasting and starvation.

In contrast, cats are obligate carnivores and consume a diet high in protein in the wild. They typically use proteins for energy and produce glucose via the gluconeogenesis pathway, regardless of fasting or starvation. Glucose can be stored in the tissues in the form of glycogen (Reference 2).

#2. Cats have low levels of the enzymes needed to digest carbohydrates in their saliva and gastrointestinal tract. However, recent studies have found that adult cats can digest carbohydrates added to a meat-based diet, providing the starches and grains are processed appropriately, for example, by cooking.

These studies also show that cats can increase or decrease protein metabolism depending on how much protein is available.  For this to happen, the cat has to eat a minimum amount of protein. After that threshold (about 15% metabolizable energy in cats) is reached, cats can use carbohydrates to produce glucose, sparing the proteins for other essential processes in the body, such as building and repairing tissues and acting as hormones. (Reference 3)

feeding your cat – make sure your cat eats every day

The Process of Starvation

Cats are designed to eat frequently.  When faced with dwindling food supplies, the cat will initially use glycogen for energy.  Once glycogen stores are depleted, amino acids are mobilized from lean muscle. Within a few days, the cat’s body will start to use fat stores for energy.

The fat moves to the liver to compensate for the fat that would normally be eaten in food. The cat’s liver can only process so much fat at a time and, consequently, fat can accumulate in the cat’s liver (“fatty liver syndrome”) and prevent the liver from functioning properly.

Hepatic Lipidosis – “Fatty Liver Syndome”

  • The liver of a cat with hepatic lipidosis may triple in size due to accumulation of fat.
  • Hepatic lipidosis is associated with anorexia (not eating).
  • The onset can be rapid, maybe 2-7 days.
  • Hepatic lipidosis can be FATAL!

Treatment of the Yellow Cat

The typical patient with hepatic lipdosis is a cat around 7 years old who is overweight. Clinical signs include lack of appetite, vomiting, diarrhea and lethargy. As the disorder progresses, the cat’s ears, mouth and skin may take on a yellowish hue.

Cats with hepatic lipidosis require nutritional support and intravenous fluids to correct dehydration and electrolyte imbalances. Diagnostic bloodwork is done to identify possible underlying disease.

A feeding tube may be passed through the nose into the stomach or placed surgically in the esophagus via an incision in the neck.

With appropriate care, most patients survive although recovery often involves 3-6 weeks of tube feedings.

#3.  Please seek veterinary care promptly if your cat does not eat for 24-48 hours. Hepatic lipidosis is less costly to treat and the prognosis is better the sooner treatment starts.


Your cat evolved to be a superb hunter.  Along the way, her body adapted to a diet high in animal protein with a unique physiology and metabolism.  Here are three things to remember when feeding your cat:

  1. Choose a food formulated for cats to ensure that she will get all the essential amino acids she needs and enough protein.
  2. Cats can digest carbohydrates that have been processed appropriately if they consume sufficient protein.
  3. Make sure your cat eats every day. Seek veterinary care if she does not eat for 24-48 hours.
Daily Food Portion Cat
Gus looks at his daily food allotment. Treats count!


1. Danks, Lee. “The cat as a carnivore: proteins, carbohydrate and beyond” (viewed 4/29/23)

2. Schermerhorn, T. Front. Endocrinol., 03 December 2013, Sec. Clinical Diabetes,Volume 4 – 2013 |

3. Laflamme, Dottie “Focus on Nutrition: Cats and Carbohydrates: Implications for Health and Disease”, Nutrition Compendium January 2010 (Vol 32, No 1).


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In celebration of Earth Day, this week’s post continues to focus on sustainable cat care. One of your cat’s essential resources is his litter box. Litter boxes are typically made of plastic but there are many choices of litter box filler. How can your choice of cat box filler help in reducing your cat’s carbon pawprint?

What makes a cat litter sustainable?

  • Made from renewable resources
  • High absorbency to reduce the amount needed
  • Biodegradable

Reducing your cat’s carbon pawprint: sustainable cat litters

the scoop on kitty litter

Kitty litter is the brainchild of Edward Lowe. He began promoting fuller’s earth, an absorbent clay, as  a cat box filler in 1947. Previously sand and ashes had been used as cat box filler – neither had the absorbency of the new clay product.

Clay cat litters are still with us. The original kitty litter was a non-clumping litter. In 1984, Thomas Nelson developed clumping cat litter using calcium bentonite. Clay materials dominated the cat litter market in 2021 with a share of 83.6% per Grandview Research

Clay Litters are not sustainable

These materials come from strip mines. Not only are they not renewable (at least in our lifetimes), they wreak havoc on the environment. They are not biodegradable. They are, however, relatively inexpensive.

Alternatives to Clay Litters

Other types of litters include those made from silica, recycled paper, wood, corn, peas, walnut shells, coconut husks, and grass.

Cat litter made from silica (crystal litters) and diatomaceous earth also must be mined. Diatomaceous earth is the fossilized remains of tiny aquatic organisms called diatoms – again, these litters are not renewable and not sustainable.

Recycled Paper

Litters made from recycled paper come from sustainable sources. However, some paper litters are not very absorbent and have to be changed frequently.  This may contribute to increased mass in a landfill. Paper is biodegradable.

Clumping or non-clumping?
Clumping litters make it easier to scoop the litter box frequently (at least once a day!) The clumping litter sticks to the waste and keeps it from contaminating the remaining litter. It more likely that you will dump non-clumping litter more frequently because the soiled litter with  mixes the non-soiled litter.  Using non-clumping litter may increase the amount of litter in the landfill.

Plant-based Litters

Plant-based litters are made from corn, peas, wheat, wood, and even tofu by-products. Starch and plant fibers such as guar gum make these litters clump. These litters tend to be lighter, less dusty and more absorbent than clay litter and are biodegradable. They are unfortunately more expensive than the old clay standby but they are sustainable.

  • You can grow more plants to produce more litter.
  • The growing and harvesting methods do not damage the environment as much as strip mining.
  • Plant-based litters are more absorbent than clay and less plant-based litter is needed for the litter pan.

A Better Mousetrap?

The Tidy Cat Breeze system uses zeolite pellets on a grate with a disposable pad underneath to catch liquid waste. Per the manufacturer, the pad is changed every week and the pellets monthly.

Zeolite is another mined material so loses some marks in sustainability although some people wash and reuse these pellets. This can extend the life of the pellets by a few months. The absorbent pad is plastic-backed so this is more plastic to go in the landfill.  Another downside to this system is you may have to train your cat to use it – cats prefer softer finer particles in their litter.

litter in the landfill

 Disposal options for cat litters include landfills, flushing down the toilet, and composting.

  • Clay litters cannot be flushed down the toilet or composted.
  • Even biodegradable litters may not degrade much in a landfill.
  • Although much of the plant-based products can be flushed, there are the risks of clogged plumbing and introduction of pathogens into the water supply.
  • These litters can be composted although there are concerns about parasites and bacteria from decomposing pet waste.

Composting cat litter
This is a controversial topic. Although plant and paper-based soiled cat litters can be composted, home compost piles do not get hot enough to kill pathogens so you certainly do not want to use composted cat litter on vegetable gardens.

Reducing Your cat’s carbon pawprint using sustainable cat litter

As the sun sets on 2023 Earth Day, here are some conclusions:

  • Clay and other mineral based cat litters come from limited natural resources and are not sustainable.
  • Paper and plant-based litters come from renewable resources, are biodegradable, and more sustainable.
  • Paper and plant-based cat litters absorb more liquid than clay litters so not as much litter is needed in the litter tray.

If you are interested in reducing your cat’s carbon pawprint, consider trying the paper and plant-based litters.

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Can insect-based cat food help you reduce your cat’s carbon pawprint?

Sustainability is a word you hear a lot these days, as more and more people compete for natural resources and deal with the effects of climate change. Sustainability is defined as “meeting the needs of the present without compromising the ability of future generations to meet their own needs” (United Nations Brundtland Commission 1987). So, you recycle plastics, take reusable bags to the grocery store, and limit the use of your car to reduce your “carbon footprint”.

How can you care for your cat sustainably? How can you go about reducing your cat’s carbon pawprint? In this post, we will talk about one of the recent trends in pet food aimed at sustainability: the use of insects as a food source (Reference 1)

reducing your cat’s carbon pawprint

Do Insect-based Foods Provide Sufficient Nutrition for Cats?

Our cats are obligate carnivores and are designed to eat primarily meat. Since many of our cats live indoors with us, they are not out hunting – we provide them meat-based cat food. Raising food animals (chickens, cattle, pigs…) for pet food produces significant amounts of greenhouse gases (carbon dioxide, methane, water vapor…)  and so is not very sustainable.

Insect Nutrition

  • Meal made from insects has as much protein as animal meal.
  • Insects have amino acids that are very similar to those in animals and cats are able to digest these.
  • Insect larvae are a good source of energy due to their fat content.
  • Insects are rich in minerals and provide necessary dietary fiber.
  • Insects are more protein dense – per weight, it takes 3 times more chicken leg meat to provide the same protein as insect meal.
  • Insects make up 2% or more of a feral cat’s diet.

Reducing Your Cat’s Carbon Pawprint by Feeding Insect-based Foods

  • Insects require less water and land use than food animals.
  • There are lower greenhouse gas emissions when farming insects compared to food animals.
  • Mealworms and fly larvae convert 45-55% dietary protein into edible body mass compared to the 33% conversion rate of a chicken.
  • Insects can feed on fruit and vegetable by products, household waste, slaughter plant waste and convert this into edible food.

What Insects are Used for Pet Food?

There are three insects currently used in animal foods: black soldier fly larvae, mealworm larvae, and adult house crickets. Black soldier fly larvae are most commonly used in pet foods.

Are Insect Foods Safe for Our Pets?

The insect larvae are blanched, chilled or frozen, then dried and ground into meal. In the process, moisture is removed, reducing microorgansims and inactivating enzymes that cause spoilage.  Heat treatment of the meal when making pelleted foods helps reduce bacteria and microorganisms.

Most insect bacteria and viruses usually do not affect animals and humans.  However, insects can be vectors of some pathogens, parasites, and prions.  Feeding the insects on vegetable waste (and not animal waste) makes insect food safer.

More studies aimed specifically at cats eating insect-based foods are needed.

Do I want my cat to eat bugs?

In Asia, Africa and South America, it is not uncommon to find insects on the menu. Chapulines or fried grasshoppers can also be found in restaurants in Mexico and even in California and Texas. However, insect consumption is not widespread in western countries.

Researchers from Oklahoma State University conducted a survey of 1,021 Americans in 2021 to see if they would be more willing to consume food containing powdered crickets than raw oysters (a food that although widely eaten is viewed as “yucky” by some). The findings: about one-third of Americans are willing to both try and consume insect products on a regular basis, provided they are tasty and safe to eat. (see Reference 2)

Another survey (Reference 3) in the United States that targeted dog owners found that participants:

  • were more likely themselves to try food made with insect flour than to eat the whole insects
  • were  more willing to incorporate insect meal but not whole insects into their dogs’ diets.

Where Can I Buy Insect-based Cat Food?

A casual Internet search turned up a handful of companies marketing cat foods with insect protein.  Most of these are based in Europe and Asia.  The only cat food that I could easily purchase in the US is made by the Canadian company Catit.  Catit offers dry cat food mixes of insect protein with chicken or herring called Catit Nuna. I contacted Catit regarding feeding trials with these foods.  They responded that Catit Nuna is formulated by pet nutritionists and has undergone feeding trials per AAFCO protocols for acceptability, digestibility and palatability.

Insect-based cat foods certainly sound like they may offer some options in reducing your cat’s carbon pawprint. However, it looks like we will need to wait for more research and development before these foods become mainstream.


  1. Valdes et al., Insects as Feed for Companion and Exotic Pets: A Current Trend. Animals 2022, 12, 1450.
  2. Melissa Reed, Bailey F. Norwood, W. Wyatt Hoback, Angel Riggs, A survey of willingness to consume insects and a measure of college student perceptions of insect consumption using Q methodology, Future Foods,Volume 4, 2021,100046,ISSN 2666-8335,
  3. Jennifer E. Higa, Matthew B. Ruby, Paul Rozin, Americans’ acceptance of black soldier fly larvae as food for themselves, their dogs, and farmed animals, Food Quality and Preference,Volume 90,2021, 104119, ISSN 0950-3293,


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A safe place for a cat when visitors come. This cat can CHOOSE to go higher or to another room if he wants to avoid strangers.

The doorbell rings and your cat runs and hides under the bed. You answer the door and your friend comes in. After some small talk, she says “By the way, how is Fluffy?” You explain that Fluffy is fine and is hiding – she just isn’t a very friendly cat.

The cat afraid of strangers may freeze or feel she has to protect herself with her claws and teeth during her veterinary exam.  Medication and training help but these will work better if your cat has some ongoing positive or at least neutral experiences with strangers.

Socialization for the cat afraid of strangers

Kittens handled gently and appropriately by a variety of humans when they are 2-7 weeks old (the sensitive period) quickly learn to accept people and enjoy being with them.

That is fine and good you say, but my cat is older now and I don’t have a time machine. It is true that we can’t have the same impact on an older cat as a kitten.  However,  we can still provide the older cat positive, predictable experiences with humans in and outside the cat’s household.

Ways to Socialize the cat afraid of strangers

Safe Places
Consider having some high perches or maybe a cat tree in your living room. Cats are curious folk and want to satisfy their curiosity if they can do it safely. A high perch or cat tree allows a cat to CHOOSE to interact or not.

CAT guidelines – Rules for Humans!
If a cat anticipates that a human will treat her in a positive and predictable way, she will be more likely to interact with that person. The CAT human-cat interaction guidelines  developed at the Battersea Dogs and Cats Home, aim to make cats more comfortable when interacting with us and are easy follow.

Point out these guidelines to guests and ask that they follow them. The video version may be more appealing to children. After a few experiences of visitors seemingly ignoring your cat, she may start to show up when strangers come over.

Desensitizing Your Cat to the Sound of the Doorbell
Doorbells can be noisy and startling.  After all, doorbells are designed to alert us to deliveries or the arrival of visitors.

  • Record the doorbell sound on your phone.
  • Lure your cat to her high perch or cat tree in the livingroom.
  • Play the doorbell sound at a very low volume and offer her a high value treat.
  • Lure her down with target stick or treat. Repeat.

Gradually increase the volume of the doorbell sound over time. The doorbell will still be an unexpected noise but now has a positive association with it. You can also use the doorbell sound to cue your cat to go to her safe place (very useful if you have a door-dashing cat).

The Calm Before The Storm

For big holiday gatherings, you may also want to consider giving the cat afraid of strangers a supplement such as Zylkene or Anxitane a few days before the big event. These non-prescription supplements can make your kitty feel calmer when lots of unfamiliar humans are around.

Regular veterinary care is an essential part of a long and pain-free life for your cat. Regular visits can head off problems and spread veterinary costs out over time. Desensitizing your cat to strangers can help reduce his fear and anxiety at the vet clinic, making it easier to take him to the vet.

If you have concerns about how your cat is handled at the veterinary practice, consider taking your cat to a Cat Friendly practice, where staff is trained in feline handling techniques.

This is the final post in the “Better Vet Visits for Your Cat” series. I hope you try some of the techniques suggested in these posts. Remember to break things up in simple steps that your cat can understand and master. And, always try to see things from the “feline purrspective”.


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