Drastic Diet? Thoughts...?

Adopted a cat yesterday.

She weighs 11.47 lbs.

Both the shelter and a new vet recommended that Josie should shed some pounds; I agree.  Both the shelter and the vet thought somewhere between 9-10 lbs would be ideal;  I also concur.

That said, it is my understanding that the average cat should receive 30 kcal/lb/day to maintain their existing body weight. For her existing weight, that would be approximately 344 kcals/day (30 x 11.47)

The shelter recommended that she be fed 235 kcalories per day.  That works out to being 68.29% of the total kcalories necessary to maintain her current weight.  The "nutritionist" at the vet today recommended that she only be given 200 kcalories per day.  That works out to 58.12% of the total kcalories necessary to maintain her current weight.

The dilemma:  It is my understanding that a cat should never be given LESS than 85-90% of their existing total kcalorie intake when on a diet, lest take the risk of them going into hepatic lipidosis -- resulting in liver failure and possibly death. That is to day, if she's been on a diet of 344 kcals/day, maintaining her existing 11.47 lbs of weight, she should be given no less than 292.4 kcals/day (85% of 344).

I am apprehensive about decreasing her intake so drastically.

Do other folks have any thoughts on this they would like to share?

Thanks,

CheetahCats

CheetahCats said:

Adopted a cat yesterday.

She weighs 11.47 lbs.

Both the shelter and a new vet recommended that Josie should shed some pounds; I agree.  Both the shelter and the vet thought somewhere between 9-10 lbs would be ideal;  I also concur....

The dilemma:  It is my understanding that a cat should never be given LESS than 85-90% of their existing total kcalorie intake when on a diet, lest take the risk of them going into hepatic lipidosis -- resulting in liver failure and possibly death. That is to day, if she's been on a diet of 344 kcals/day, maintaining her existing 11.47 lbs of weight, she should be given no less than 292.4 kcals/day (85% of 344).

Click to expand...

Thanks for saving Josie!  

I agree with you, 100%   

There is no need to put her on a "crash" diet. Losing weight slowly is much safer and healthier for her.   

If you pet her on a primarilly wet, low carb, grain free diet, that will allow her to lose weight naturally.

My Kitties are loving Wellness Chicken - also Turkey and Turkey & Salmon on occasion.

Thanks for your prompt reply, SevenWonders. 

I appreciate it.

I recently saw a sheet which listed the kcalories for each of the major cat food brands. According to it, Science Diet Original is 493 kcals per cup.

Using lunidoo's post which lists the average amount of kcals a cat needs per kilogram in weight, I adjusted for pounds, and came up with the following spreadsheet. (2.2 lbs per kilogram):



Thus, per my calculations, she should receive 130.45 grams of Science Diet per day.  It would be 90% of what she has been getting, and wouldn't seem to risk any chance of hepatic lipidosis.

And at the end of the month, when she's reweighed, the numbers can be readjusted according to her new weight.

If anyone sees a blatant error in my assumptions or calculations -- or would like to share their thoughts -- please chime in!

Thanks, kindly

CheetahCats

Aw, I agree! Thanks for rescuing Josie! If you know what she was eating and how much of it, then using 90% of that is a good approach.

However, just as people have varying rates of metabolism, and age and level of exercise/energy use vary considerably between cats, there is no one number of calories per pound that can be used to calculate how many calories per pound are required. The rule of thumb our vet uses is 25 calories per pound, but if you do even a short, limited search online, you'll find the recommended amount of calories per pound ranges from 15 to 45! For feeding wet food, if looked at in ounces per pound, the range is typically 0.5 oz per pound to 1 oz per pound, another range so wide you could drive a truck through it. And for raw feeding, the recommended amount of food is 2% - 4% of the cat's body weight.

I found, when feeding wet food, that my cats need about 15 calories per pound (on average). They're older, and weren't terribly active.

All of that said, cats' bodies work much differently than people's bodies do. Cats are carnivores, and one of the reasons they run the risk of hepatic lipidosis at all is because they are not designed to "store" fat for potential future use as energy. Cats have zero nutritional requirement for carbohydrates. Their bodies do not use carbs efficiently, which is why they have the tendency to gain weight on a diet high in carbohydrates. People are designed to store fat as future energy. When we consume less calories and exercise, we burn fat and lose weight. While the same basic principle is true for cats, because they are not designed to burn stored fat as energy, if their diet "forces" them to burn too much excess fat at one time, it overwhelms their livers. What they need to lose weight, more than anything, is a high-protein diet at just under their daily required need. They use all of that protein for energy, and then gradually burn off their excess weight, not overwhelming their livers.

As SevenWonders pointed out, moving to a grain-free food with the carbohydrate content considered (the cans do not provide this information: you can use this online calculator http://www.scheyderweb.com/cats/catfood.html, or just take 100%, and from the guaranteed analysis provided, subtract protein, fat, fiber, moisture, and ash: what's leftover is carbs). For any cat, of any condition, the optimal diet targets only 10% carbs at most. But this is particularly important for cats that need to lose weight. They can very efficiently convert protein and the fat they're eating into energy, but the carbs not so much. This is part of why there is a HUGE range in calories required per pound. Cats eating a high-carb diet need more calories per pound, because they do not use those calories efficiently. Cats eating a high protein diet need fewer calories per pound, because they use those calories far more efficiently.

If you want to compare wet food and dry food, you really need to analyze the foods on a dry matter basis (remove the water content of the foods in order to compare them on an apples-to-apples basis). You'll see that most canned foods have 9% - 12% protein, and 68% - 75% moisture. Most dry foods have something like 40% - 50% protein, and around 10% moisture. Do dry foods have more protein than wet foods? Not usually. They just look so different on the "guaranteed analysis" because of the different moisture content.

You can either download this Dry-Matter-Basis converter: http://catcentric.org/ (left side column, under Special Features - it's an excel spreadsheet), or just calculate yourself. To do this, calculate the amount of dry matter in the food: Start at 100 (100%), and subtract the moisture content. If you're looking at a wet food, let's say it's got 75% moisture. So the dry matter is 25%. If the protein content is listed as 10%, as a percent of the dry matter, that is 10%/25% = 40%. Or just 10/25 * 100. Take each component in the guaranteed analysis, and divide by the dry matter content of the food.

In a search for a high protein/low carb food, when comparing kibble to kibble, or canned food to canned food, the differences in moisture content will likely be small, and converting to a dry matter basis is not as important. But when comparing dry food to wet food, it is imperative.

But in summary, feeding her a percent of exactly what she was eating, and the amount she was eating, is a good start. But changing her diet to a high-protein, low-carb diet will be the best thing for her overall health, not just for her losing weight. Adding as much moisture as possible will also help "rev up" her metabolism, and it is NOT recommended to do this by making kibble moist.

I dunno, when we got  Sneakers she weighed 16 pounds. Vet said she should weigh maybe 12 pounds at most, maybe less. We didn't decrease her food at all, all we did was switch her to a high protein grain free diet and move the food upstairs so she had to go up and down to eat, and she lost weight. The people that had her before were feeding dry Purina Deli-cat, so it's no big surprise.

Unfortunately she's now underweight since she is now at least 17 years old and has CRF and high blood pressure...

Sneakers when we first got her:

Thanks for the input folks. I appreciate it.

I especially appreciate the links that you left LDG, and the extended time you took to providing details and background information!

I checked out the links you had provided, and was unaware they had existed.  They are very helpful, indeed

Thanks again,

Cheetah