The Guaranteed Analysis and Metabolizable Energy Numbers: How Close to Reality Are They?

As I’ve been updating this book, I’ve taken a hard look at the numbers involved. I’ve also developed spreadsheets to calculate some of the more complicated formulas. I’ve learned a few things about the numbers that I’d like to share.

Let’s first look at the Guaranteed Analysis. Want to know why every pet food company tries to steer you away from using these numbers? The reality is that there’s a huge “fudge factor” built in. The pet food manufacturing process isn’t very precise or consistent, even using the latest computer manufacturing technology (which not every company uses). The biggest variations come in the ingredients. Mother Nature isn’t consistent, so ingredients like corn can have different nutrient content, and different moisture content. Suffice it to say that  there are plenty of variables, and they all come into play to make each batch of food slightly different than  the last one.

Because of these differences, there has to be enough room in the Guaranteed Analysis so the manufacturer doesn’t bust out beyond the limit he’s guaranteeing and violate the law. In other words, if the protein level in the final product ranges from 26.8% to 27.8%, the manufacturer will give himself some breathing room and put 26% on the label as the guaranteed minimum. The same goes for the minimum level of fat, and the maximum levels of fiber and moisture.

Here are some examples of the Guaranteed Analysis and the reality, which is the Average Analysis – several samples analyzed and averaged:

Those discrepancies affect other numbers, too. The best way to determine the Metabolizable Energy (kilocalories) for example, is to feed several dogs the food, collect urine and feces, and calculate what goes in versus what comes out. But that’s an expensive proposition, and generally only the larger companies will run this test. It’s much easier to use a slightly-complicated formula, called the Modified Atwater Formula, which is based on some basic knowledge of how much energy protein, fat, and carbohydrates contain.

To show you how these figures can vary, I plugged the two sets of numbers for Iams Chunks/MiniChunks into the Modified Atwater Formula. I used the ash content from the Average Anal-ysis, and the 3.3 oz. weight of a cup of the food that Iams uses.

Based on the Guaranteed Analysis, ME is 327.5 Kilocalories/cup.
Based on the Average Analysis, ME is 347.8 Kilocalories/cup.
Based on Animal Tests by Iams, ME is really 381 Kilocalories/cup.

Just to add another layer of confusion, two formulas can be used. The Atwater Formula is the one used to calculate the ME of foods for people. It assumes a high level of digestibility. The Modified Atwater Formula includes adjustments for lower quality ingredients, such as those traditionally included in pet food. The problem is that some foods (especially raw meat diets, high meat content commercial foods, most canned petfoods and baked foods) are more digestible than ever before. Should we use the Atwater Formula or the Modified Atwater Formula? Here’s what the Atwater numbers look like. You can compare them to the Modified Atwater numbers above.

Based on the Guaranteed Analysis, ME is 364.3 Kilocalories/cup.
Based on the Average Analysis, ME is 386.6 Kilocalories/cup.

As you can see, the Atwater Formula using the Actual Analy-sis figures is almost exactly what the Animal Tests showed the real ME is. To me, that says that this food is made with the equivalent of human-grade food, at least when it comes to providing ME.

The moral of this story is that the Guaranteed Analysis has a wide margin of error built in, and isn’t a great set of numbers to use for comparison. The Average Analysis is much more accurate, but much harder to extract from the petfood companies. Iams has their numbers and plenty of other data on their website (www., but you may have to call the other companies to get the Average Analysis for other brands.

The other moral of the story is that the ME should also be considered a guideline, and another piece of the puzzle. In the example above, there was a 14% difference between the standard calculation and the real, Average Analysis-based ME.

In our reviews, the ME shown is either the number supplied by the manufacturer (which could be by calculation or by feeding trial), or one that we calculated using Modified Atwater. We ran into some cases where the manufacturer didn’t have a clue how to calculate the ME, and others where our calculations were much more accurate than theirs. We provide the numbers in which we have the most confidence. For raw food diets, we provide both Modified Atwater and plain-old Atwater numbers.

Ross Becker – 1999

How Many Calories Does Your Dog Need? How To Use The Calorie Chart

The first chart, “How Many Calories Does Your Dog Need?” gives you an estimate of how many calories your dog needs per day. It’s based on a standard formula used in the pet food industry (ME=K x Metabolic body size). Themetabolic body size is the weight, in kilograms, to the 0.67 power.) The formula is a bit complicated to calculate, so we’ve done it for you. All you have to do is look up your dog’s weight, and estimate his activity level, to find the estimated number of calories per day your dog needs.The shaded columns are a good starting point for typical dogs.

Traditionally, the industry has used activity K figures of 132 for inactive, 145 for active, 200 for very active, and 300 for endurance/performance/sled dogs. These numbers are now considered to be about 30% too high for most dogs, with 99 to 110 typical of the average house dog. Since dog food companies base the feeding recommendations on the bag on the old numbers, those feeding recommendations are about 30% too high. (One exception is the Eukanuba line, which has made the adjustment on the bag.)

To accommodate all types of dogs, we’ve provided a wide variety of activity levels. Choose the one you think is best. If you want to be safe, err on the lower side. The gray columns are starting points for three different typical activity levels. You’ll also note that the latest research has shown that working sled dogs use a huge amount of energy – vastly different from what was previously thought.

All of the estimates are based on how much energy your dog uses, and that’s the part that’s impossible to pinpoint. One dog may get the same amount of exercise as another, but use up a different amount of energy. So, use this table as a starting point only. Adjust the number of calories based on your dog’s needs, and weigh your dog every few weeks to see the result of any changes in diet.

These numbers are for ADULT DOGS only. You can adjust for different lifestages and situations like this:

Growing puppies, weaning to 11 weeks:  k=375 (1.875 x 200 column)
3-4 months Pre-Adolescent puppies K=350 (1.75 x 200 column)
5-7 months Adolescent puppies K= 225 (1.125 x 200 column)
8-12 months Teenage K=160
12 months = Adult level
Large breeds – back off 10% to 15% (65 lbs or bigger)
Pregnant, late in pregnancy                Calories x 1.5
Nursing mothers                                    Calories x 3
Prolonged physical work                      Calories x 2 or 4
Living in cold or extremely hot weather Go up 1 column in heat if panting a lot, 2 columns in cold weather

Remember, the objective is weight maintenance. Weigh your dog monthly and keep track of gain  or loss. (If you can lift your dog, you can get on the scale with your dog and subtract your weight. Otherwise, make a date to take your dog to a pet store or vet clinic that has a scale. Record the weight on your calendar.) Weight measurement is important, especially if you’re changing the diet. Don’t trust your eye – it’s very difficult to discern changes.

To calculate how much to feed, take the number of calories per day from the chart, and divide by the ME per cup listed for your dog food. Feed that many cups per day. Deduct some if you add treats, canned food, table scraps or home cooked mix-ins. We recommend feeding at least twice a day, so remember to divide the amount in two. Don’t forget to adjust the amount you feed for changing weather conditions and changing daily activity levels.

For weight loss or weight gain, use the numbers for the weight you’d like your dog to achieve.

Ross Becker

Thanks to Dr. Dan Carey of The Iams Company for the update on K figures.

Can Your Dog Get Mad Cow Disease?

Everyoneʼs been talking about BSE. Even Oprah. But what does it mean for you and your pets?

Now that BSE has been in the news in a big way, it’s time for Good Dog! to offer some comments. We’ve known about BSE for several years, but had vowed to ourselves to keep our mouths shut. We didn’t want to start a big scare if it was not warranted.

dog stethescope

Well, it’s probably still not warranted, even if you’re one of our readers living in
England and feeding a British-made food.

BSE is Bovine Spongiform Encephalopathy. It’s a mystery disease that causes the brain to turn to Swiss cheese. Well, not exactly. But the brain develops holes like Swiss cheese, and begins to look like a sponge. That’s why it’s called “spongi-form.” In sheep, the disease is called scrapie. In people, it’s Creutzfeld-Jakob Disease (CJD). A similar disease also affects cats. So far, no cases of any similar diseases have been reported in dogs anywhere in the world.

We’ve been following the story in our sister publication, Dog Industry Newsletter, for several years. Judging from the response to our articles, the American pet food industry has been quite concerned.

Here in the U.S., there have been no cases of BSE reported – even after a decade-long search by the U.S. Department of Agriculture. But steps are being taken anyway, to make sure that BSE doesn’t get a toehold here, and even if it does, that it doesn’t become an epidemic. One step being taken is a long-standing ban on the importation of meat and by-products from any country with BSE. That’s handled by the U.S.D.A.’s APHIS animal and plant inspection service (the Beagle Brigade people.) APHIS is tightening their surveillance, as are the USDA’s meat inspectors at the slaughterhouses.

A few years ago, a voluntary ban on old sheep was instituted by American rendering plants. These factories take animal carcasses and body parts not used for human consumption, and use heat to make them into meat meals for use in animal feed. The ban covers older sheep, which are more likely to have scrapie. (It takes several years for scrapie and BSE to show up, so animals under the age of one year are unlikely to have the diseases.)  In addition, the renderers will only work with  sheep carcasses that come from federally-inspected meat plants.

The last major scrapie outbreak occurred in the early 1950’s in the U.S. In 1952, there was also a major outbreak in Australia and New Zealand. Those countries killed their entire flocks of sheep, and eradicated scrapie. The U.S. sheep industry didn’t go as far, and scrapie still exists here, although on a very small scale. Still, nearly all pet food manufacturers have chosen to buy lamb for their lamb and rice pet foods from scrapie-free Australia and New Zealand.

These brain diseases are still not well-understood. They’re not caused by a bacteria or a virus, but by an unusual type of protein. It’s not alive, and therefore it can’t be killed. But high heat can inactivate the protein, to a degree.

The disease can be spread by consumption of brains and spinal cords that contain the protein. It can apparently also be transmitted through blood. Six of the ten most recent British deaths from CJD were people who had worked in jobs where their blood might have come in contact with contaminated beef. The disease can also be transmitted through blood donations from people with CJD, and through growth and fertility hormones. What’s the connection with the hormones? They’re derived from corpses, and sometimes the corpses contain the protein. Five women and one man died in Australia after receiving the hormones. One scientist in Australia estimates that there could be up to 60 cases of CJD a year in Australia. Switzerland has had four to seven cases of CJD a year between 1991 and 1995, and 68 cases of BSE in 1995, 64 in 1994. No cases of BSE have been reported in the U.S.

Cats are affected, too. In the past six years, 70 domestic cats have died from encephalopathy in the United Kingdom. They call it “mad cat disease” there. The speculation is that the disease was transmitted through pet food containing the remains of BSE-infected cattle.

Various countries have been taking action to protect people and pets from the BSE family of diseases. The United Kingdom’s Pet Food Manufacturers’ Association introduced a voluntary ban on what is euphemistically called “specified bovine offal” of SBO. The voluntary ban went into effect before the government introduced legislation in June of 1989. The ban on SBO in human food followed five months later.

Andrew Mackin, an animal nutritionist at Edinburgh University’s Royal Dick Veterinary College said, “It would have been safer to eat a tin of (dog food) than a beef burger in summer, 1989.” Speaking about today’s products, he said, “Pet foods are highly processed and sterilized to a very high standard.”

As for the need for a study of the problem in animals, the question of statistical significance comes up. A British Ministry of Agriculture spokesman said, “There have only been 70 cases out of a (current) cat population of 7 million. They need something like 200 cases to form a proper study and to come to any proper conclusions.” Remember, though, that those 70 cases occurred over a long period of time, and out of many millions of cats. And most of the cases occurred in older cats, who were alive before the ban on SBO.

Meanwhile, the British government is considering banning the use of all mammal protein in pet food and other animal feed. The government just rejected a plan to do a mass slaughter of all British cattle to restore confidence. But the damage has been done to the reputation of British foods abroad. Glen Brookfield, Route Managing Director for Pets Choice Ltd. said, “The problem is market forces … we spent two years penetrating the French market and just as we managed it, we’re out overnight.”

The Japanese have extended a 45-year ban on British beef imports to include pet food. “Japan has not allowed imports of beef from England, but it is possible that some beef is contained in pet food,” Agriculture Minister Ichizo Ohara told the Japanese Parliament. “We will inform the British Embassy here of the banning of all imports of beef products, including processed foods.”

Switzerland has also banned the use of meat, offal (by-products) and bone meal in animal feed. All cattle, sheep and goats more than six months old must be examined by an expert before slaughter, and all animal owners must report animals suspected of sickness to a veterinarian.

Here in the U.S., the Department of Agriculture is increasing its role in surveillance inspections for BSE. Inspectors from the Food Safety and Inspection Service will now look for any animals that show symptoms associated with BSE. There are specific procedures they’ll follow to insure that those animals are kept out of the meat or feed supply. The U.S. has not imported processed beef, or cattle, from the United Kingdom since 1989. Similar stringent restrictions on the importation of cattle and beef protect us from the possibility of BSE coming in from other countries where it is prevalent.

The USDA has examined over 2,660 suspected animals from 43 states, and hasn’t found BSE in American cattle. On March 22, the USDA held a meeting with 70 people from various international health authorities, state and public health agencies, the scientific community and industry. The goal was to discuss the situation and see what could be done to further prevent the spread of the disease.

Meanwhile, the U.S. Food and Drug Administration (FDA) is considering a ban on the use of cattle and sheep remains in cattle feed. The agency is considering whether to issue extended regulations based on an August, 1994 proposal to ban the use of goats and certain parts of sheep in animal feeds. According to the experts at the FDA we spoke with, the regulations will codify the voluntary ban on feeding ruminant by-products to other ruminants. A new proposed regulation is being drafted now. The purpose behind this regulation will be to add another layer of safety into the food supply. If there were a case of BSE, it would not be spread in animal feed, and an epidemic would be prevented. The safety factor would help protect people as well as food animals and pets.

Another safety factor involves the way meat meals are processed in the U.S. A new study shows that in Britain and other European nations, four of the 15 rendering processes used aren’t hot enough to inactivate the protein. In the U.S., renderers have always used high-temperature rendering. (In England, farmers used to feed their baby calves “greaves,” which were by-products that were not fully rendered. That practice has now been stopped.)

What does the FDA say about pet food? Dr. David Dzanis of the FDA’s Center for Veterinary Medicine says he sees little cause for concern. He told Good Dog! “There have been no reported cases of brain diseases like this in dogs, anywhere in the world. (See article below for an update.) The U.S. is currently BSE-free, and our high-temperature rendering processes would help inactivate the protein that causes BSE. Add to that the extra steps that are being taken to prevent BSE from getting into the country, and the ruminant to ruminant ban that’s being implemented voluntarily, and you’ve got a very safe pet food supply.”

Keith Hansen, Nutritionist for Merrick Petfoods (which owns its own rendering plant), concurs: “We have, without question, the safest beef supply, and the safest feed supply in the world.”

But the whole issue might become moot, sooner, rather than later. A new, simple test for BSE and similar diseases has been developed which appears to be accurate in people, cows and other animals.

Dr. Michael Harrington, of the Cali-fornia Institute of Technology in Pasadena, California, is working with scientists from the U.S. National Institutes of Health in Bethesda, Maryland. He expects to submit a paper on the new test to the peer-reviewed New England Journal of Medicine in the next few weeks.

Harrington, a native of Glasgow, Scotland, said he identified two proteins 10 years ago. These proteins are present in cases of CJD, and in the similar diseases which affect animals. His first test for the proteins, developed a decade ago, was too technologically complex for widespread use.

Dr. Harrington told the Reuters wire service, “The test has been available but no one has done it. Why is that? Because the technology is really more than hospitals and clinics will ever do. It takes about three days to do and they just don’t like the technical complexities.”

Harrington received funding a year ago to devise a simpler test. The new test uses an antibody to identify the proteins, which he has numbered 130 and 131. The same two proteins, or markers, which are extracted from spinal fluid, are also found in cows with BSE. Using the new test, a handful of technicians could test up to 2,000 cows a month.

Harrington said that in the thousands of human cases he has examined using the old test and the new test, only three diagnoses were found to be inaccurate. The tests he has run on cows and other animals, while accurate in detecting spongiform encephalopathy such as BSE, have only been used on a small number of animals.

With this new test, Harrington believes that cows with BSE could be singled out. But more rigorous testing of the test is needed, according to Harrington. Once his data is published, other scientists can work with the procedure.

It’s still not known how early the two proteins appear during the development of the disease, which has a long incubation period. “But that can be evaluated once people get hold of this marker and start studying it,” Harrington said. “One can look at it experimentally and find out how early it appears in the course of the disease. Then we’ll have some idea, (if) this appears only in the established clinical syndrome in the animal or the human, or (if) it appears  before that.” In other words, will the marker be detectable ahead of the symptoms?

What does this all mean to you and your pets? Not a whole lot, at this point. Our advice is to stay calm, and to not fret. The food supply in the U.S. is quite safe right now, and even more precautions are being piled on, just in case. So all you  have do to is watch the situation and see if it changes. If you’re exceptionally concerned and have to do something, you can feed a chicken or poultry-based food. These brain diseases don’t affect any birds, including chickens or turkeys. (Then again, they don’t affect dogs, either, so why worry?)

The bottom line is that there’s no need for concern at this point. The pet food industry is watching carefully, the U.S. Department of Agriculture is watching carefully, and the Food and Drug Administration is watching carefully. So far, so good. But we’ll be watching carefully, too, and we’ll let you know if there are any further developments.

Poop Eaters Anonymous

What do you do with a dog who eats feces?

Anna Lee Rucker

The subject of coprophagia is taboo. This may be because it’s impossible to pronounce, difficult to spell, and hard to remember. Most of all, people just don’t want to know about it.

It’s hard for us dog-lovers to accept such a truth about our beloved dogs. After all, who wants to be kissed, rather wetly, by a dog that eats his own – or other animals’ feces?

Perhaps there’s another reason we hesitate to mention it – we feel there are more pressing problems that crop up with dogs. Coprophagia isn’t particularly harmful to the animals and, anyway, there’s no absolute cure.

There are several theories about the cause(s) of coprophagia in dogs. One is dietary deficiency. Another is boredom associated with kennel life. Maybe they experienced neglect or another traumatic experience. (This is especially true in dog rescue situations.) Or could be they do it because they’re dogs and they like it!

I’m inclined to believe that female dogs are more prone than males to engage in this forbidden passion – a leftover from cleaning their puppies. When males do it, it’s more out of curiosity or stark boredom. Or they just want to irritate and intimidate us!

Let me tell you my main reason for choosing to “go public.” I hope to convince breeders to make sure their puppies don’t leave for new homes unless this habit – often formed in puppyhood – is broken. If it isn’t, we may be sending our precious puppies to a lonely backyard existence. This could very well happen when owners see the habit for the first time and realize they have no tools to fight it.

There’s another reason, just as important. I’d like to give the wonderful people who take in rescue dogs that have this habit some hope. I don’t have a lot of remedies, but what I have, I offer to anyone who wants to try.

My first purebred dog shocked me with her craving for horse manure! I took her to the vet, where I heard of this disease for the first time. I tried what he suggested, to no avail. So I simply decided not to take her to the park where she encountered that particular delicacy.

That was her cure. She never carried her peculiar vice over into the dog world. On the other hand, my mutt, who lived with this dog, would’ve died before engaging in such an atrocious habit!

Actions and habits are not the same. I think habits can lead to addictions, but habits are changeable and curable. Curable addictions are another matter.

My next encounter with copro-phagia (I’m trying desperately to spell this word the same way twice!) was with my first show female. I got her after she had already been on the show circuit. I soon learned that she was addicted to her own poop. After 15 years, she still is! I tried everything: advice from the vet; supplies from a catalog; racing to her with my pooper-scooper (a race she always won). I changed her diet numerous times hoping that the diet-deficiency theory would prove correct. We still struggle over this problem, but I mostly just turn my head.

Now this plague has raised its ugly head again. I’m cursed! This time it’s a beautiful female that I rescued. Evidently she had lived with one person she adored for about four years. Then she went to a kennel owned by a friend of the dog’s owner. She stayed in that kennel about eight months. Next, she was placed in a home that didn’t work out because she “chased our cats.” Finally, I put her with a girl who was active in 4H work. That didn’t last. So I brought her home.

A woman in another state heard about her through our rescue network. She wanted her. I was so excited! Here, at last, was a good home. I had the dog spayed and, while she was recuperating, I learned of her addiction to poop.

The prospective owner had already sent air fare to have the dog shipped to her. But I felt compelled to explain the problem. She had never heard of such a thing! I told her to discuss it with her veterinarian who advised her (she was quite elderly) not to take on a problem dog. The woman was thoroughly disappointed and made me promise that I would be sure she got a very good home. I promised.

Missy had other problems. She stuffed her blanket into her water bowl several times a day. She wouldn’t look at me, but past me, as if searching for the someone dear to her. She didn’t feel well. She had tapeworms. Her surgery revealed massive infection in her uterus. And it was some time before she felt like eating again, even after the infection cleared up and the tapeworms had gone.

My diagnosis was that Missy was a heartbroken little dog that had gone from a loving situation to the coldness of kennel life … to a yard because she chased the house cats … to someone who didn’t want her, after all …  and on and on. She seemed unable to adjust to any further changes in her life. Any wonder?

The first time I saw Missy engage in coprophagia, I reacted without thought – just pure disgust. I screamed, “No!”

Whether it was the word or the scream, Missy quickly abandoned her actions. But I had frightened this already miserable little dog. As I screamed, I realized that I couldn’t send her to her new home – I was stuck with another dog I had no room for. Immediately, I was ashamed of myself. I knew I would accomplish nothing by screaming at her. Missy became my newest project involving coprophagia. She was my experiment.

I knew it would take time – time that most people don’t have and a few won’t take. I accompanied Missy each time she went outdoors. When she attempted to eat her feces, instead of screaming at her, I called to her, cheerily, “Missy, Come!” To my amazement, she came charging across the yard and jumped on me! I always carry doggie biscuits and I offered her one while lavishing praise on her. “Good girl! Good girl, Missy!” She wagged her tail unmercifully!

What magic the biscuit and praise had produced. Was it a one-time thing? Well this little dog came every time after that. She had been so eager to please me and now she had found a way!

At other times, I watched her scavenging the yard. When she found poop left over from my clean-up job, I realized I had a bigger problem than with my first Cairn Terrier or my first show Cairn. Missy wasn’t as selective as the other two!

Now what would I do? I had my pooper-scooper in hand. I popped her gently on her rear and said, “No!” This time I didn’t scream. She circled me slowly, as if considering whether she wanted to give up her prize. Then she came and laid it before me. “Thanks, Pal,” I lied, but I didn’t give her a treat. I pointed to what she had brought me and quietly said, “No.” She never did that again.

It’s hard to determine a Cairn’s goal when she puts her nose in the grass and begins trailing away. Is she scenting squirrels? Cats? But all I had to do to be sure Missy wasn’t looking for poop was to pick up the pooper-scooper. She never really seemed to fear the scooper. It worked more as a signal than a threat.

I continued going outdoors with her. Our game never varied. Then I had to kennel all my dogs for about two weeks. I worried most about Missy: I’d have to regain her trust and I’d have to train her to stop.

Wrong! All the other dogs were now engaging in coprophagia –  but not Missy! She returned to our game immediately. With the others, I finally had to take each dog, individually, into the yard and “discuss” the fact that their poop belonged in my pooper-scooper! After several days, they returned to their previous acceptable behavior. They had begun to form a habit; theirs was not an addiction.

I placed a puppy for a friend about a year ago and one day the new owner invited me to come see her puppy.

When I got there, she told me her dog had a disgusting habit, but she didn’t know exactly how to say it. I told her that what her puppy was doing was natural and that many puppies did it. But I knew that if something couldn’t be done, she’d get rid of the puppy! I suggested crate-training the same way as for housebreaking. She thought crating was cruel until her vet told her the same thing. She crated the dog, even when she was home, and took him outside at the appropriate time until he learned where he was supposed to do certain things. Crate training worked for her.

The usual pet owner doesn’t want to have to cope with this particular habit. I always fear they’ll put the dog outdoors all the time and begin to neglect him. If we can prevent that by discussing the subject, maybe we can do some good by bringing it out of the closet.

It’s the same with rescue dogs and the people who take them. Lots of love, a little patience and time, plus some consistent discipline will help your dog overcome coprophagia unless it has become an addiction. Then, well, what can I say … you’ll just have to learn to turn your head, grin and bear it! Well, at least bear it.

I now trust Missy to go outdoors for her final time at night and for her early morning outing. I watch at the door. If she makes a “deposit” at either time, I’m there with her biscuit and lots of praise. I kept my promise to the lady in the other state, also. I made sure Missy went into a loving home … mine!

And wouldn’t it be great if someone came up with a magic pill for this problem?

First published in Canine Classified, July, 1994
Illustration by Melani Nardone.


Should You Add Anything To Your Dog’s Food?

Many people think it’s great to add fresh fruit and vegetables to their dog’s diet. They think that fresh foods will give their dog something that a processed food won’t. Some people even think that fresh foods are the only way to add “life force” to the diet.

While we won’t debate the issue of life force, adding foods to an already complete and balanced diet can cause some problems. Any additions to an already complete and balanced diet are likely to throw the finely-tuned balance of nutrients way off. For example, if you give your dog cottage cheese, milk or ice cream, the additional calcium could create a zinc deficiency and you will probably see flaking skin, and, possibly, other problems, too.

Fresh fruits and vegetables contain plenty of water. Cooked vegetables contain even more water. Believe it or not, adding extra water to the diet dilutes the nutrients your dog is getting from his food.

Since fruits and vegetables also contain carbohydrates, you’re diluting the prepared diet with those, too. Because you have added calories to the diet, you are diluting the amount of protein your dog is getting, as your dog will want to eat less of his dog food.

The additions you make to the food may also result in the undersupplying of different vitamins. While there is a margin of error included in the formulation of the dog food, how close to the wire are you getting?

What about adding rice? Rice is just water and starch – carbohydrate. Now you’re diluting the dog food with water and carbohydrates. The more you add, the more you dilute, and the less the dog gets of the balanced diet.

How about celery? Although it’s one of my favorite snacks, celery is worthless to the dog. It contains plenty of water, and is mostly fiber. The fiber takes up space in the stomach, so your dog will eat less of the food (and therefore the nutrients) he needs.

Some people like to cook beans for their dog. Well, as you may imagine, beans can cause gas in dogs. It’s not a balanced addition, and will dilute the vitamins, minerals and fatty acids in the rest of the diet.

Are fresher foods more natural and better for your dog? There’s some debate about this, but no hard evidence. Commercially-made dog foods are the result of years of nutritional research, all with the goal of providing your dog with all of the nutrients he needs to live a long, healthy life. Various analyses show that the commercial food your dog eats will provide all of those nutrients. Most manufacturers also perform standard feeding tests to make sure that their food works well in real dogs, not just in the laboratory.

Dog food manufacturers have worked hard to balance the diet using many of the same ingredients you’d add to the diet. There’s really no need to add anything else.