Carbohydrates in kibble

What is the purpose of carbohydrates and why are they essential in an animal's diet?

Carbohydrates (more commonly known as "sugars," or formerly, "carbohydrates") are the primary source of energy that the body can easily use and mobilize, for example, during physical exertion. The carbohydrates contained in food are an important source of energy. Therefore, they should not be neglected. However, in cases of diagnosed pathologies or diseases such as diabetes, it is necessary to control carbohydrate intake. This requires understanding the difference in carbohydrate content between different foods and understanding their equivalents. Carbohydrates provide glucose, the fuel for all the body's cells. Thus, for the brain, glucose is the only usable energy source (it cannot produce backup energy).

Sugars are simple carbohydrates (fast-acting sugars)

Simple carbohydrates, also called monosaccharides, contain only one basic molecule. Among them, we distinguish:

• Glucose , not very common in its free form in foods, but which is part of the composition of many other sugars;
• Fructose , present in honey and fruit, is also a component of sucrose.
• Galactose , which is a component of lactose (milk sugar), in association with glucose
• These sugars are frequently combined to form other carbohydrates called disaccharides. The most common compound sugars are:
• Sucrose , which is ordinary sugar, is composed of two molecules, one of glucose and the other of fructose; the most widespread sugar in nature, it is found in fruits and vegetables, and it can be obtained from beetroot and sugar cane;
• Lactose , a sugar found in milk and dairy products.
• Maltose , present in cereals and especially in beer.

These sugars are called "fast-absorbing sugars" because they are absorbed immediately. They have the disadvantage of abruptly stimulating the mechanisms that regulate blood sugar (insulin secretion during a meal) and not satisfying hunger for long enough. Fructose is absorbed as quickly as other simple sugars, but half is used immediately and half is stored in the body as glycogen. Therefore, its consumption does not trigger insulin secretion, unlike other "fast" sugars, which could be beneficial in cases of diabetes.

Sugars, complex carbohydrates (slow-release sugars)

Finally, there are sugars, called polysaccharides, composed of more than ten basic carbohydrate molecules (generally several thousand). Complex carbohydrates are made up of several simple carbohydrate molecules and are transformed into glucose during digestion. These carbohydrates are called "slow-release sugars" because they are absorbed gradually by the intestine. They are found in bread, pasta, rice, cereals, some fresh vegetables, and legumes. Fiber has no impact on blood sugar levels. It is initially broken down into basic carbohydrate molecules (glucose, fructose, and galactose). The main ones are:

• Starch , which is found in foods of plant origin, especially cereals, pulses, tubers (potatoes), and certain fruits (bananas, chestnuts);
• Glycogen , of animal origin, is much less widespread, and its contribution is almost nil.

Certain carbohydrate-rich foods are essential for a balanced diet. These include grains and grain products, vegetables (both dried and fresh), fruits, and dairy products. It's important to note that the carbohydrate content of fruits and vegetables varies depending on several factors, such as their ripeness, origin, cooking method, and whether they are eaten alone or as part of a meal. Other foods are essential solely for human enjoyment: these are foods containing simple carbohydrates like honey, jam, sweets, and sugary drinks. These types of carbohydrates should be completely removed from animal feed. Two different foods with the same carbohydrate content do not necessarily produce the same blood sugar spike. Some simple carbohydrates are absorbed slowly, while others are absorbed quickly. The rate at which a carbohydrate is digested depends largely on how it is consumed: cooking method, whether it's eaten alone or as part of a meal containing other nutrients such as fats, proteins, or fiber. This is why carbohydrate equivalents can be adjusted using the glycemic index. Therefore, favor foods with a low glycemic index, such as pasta cooked al dente, rice, and legumes, and limit (but do not eliminate) foods with a high glycemic index. Note : Cellulose, found in plants, forms the structure of plant fibers that facilitate intestinal transit, but it is not absorbed by the body.

Understanding the Glycemic Index in our pets

Glycemic Index and Diabetes in Dogs and Cats (based on the Veterinary Medicine thesis by Nicolas Georges PUCHEU) Excerpt: We will try to understand how to adapt the concept of the glycemic index to domestic carnivores, and what its benefits would be. While the glycemic index of many foods has been measured in humans, this is not the case for animals, for several reasons. First, a species-specific index is necessary. Indeed, depending on the digestive characteristics (enzymes, chewing, etc.) specific to a species, it is not necessarily possible to predict the index of a food from an index measurement in another species. It is therefore necessary to measure the index of each food for a given species, which is long and tedious, and often of little use. Furthermore, the diet of domestic carnivores is very different from ours: they generally do not consume the same foods, nor the same quantities, as humans. Almost all the results obtained in humans, if they could simply be extrapolated, would therefore not be of great interest. To date, and to our knowledge, no measurements of the glycemic index have been carried out in animals. The closest experiments were conducted in dogs in 1998 and 2001. Without specifically measuring a glycemic index, Nguyen et al. determined in 1998 the glycemic and insulinemic responses following the ingestion of commercial foods [1] [44], and demonstrated that a meal richer in fiber has a beneficial effect on postprandial hyperglycemia. Hesta et al. confirmed these results in 2001 [2] .

Is man comparable to an animal?

The definition, as proposed for humans, may not be directly applicable to animals. Indeed, while some large dogs would have no difficulty ingesting food containing 50 grams of carbohydrates, this quantity is too high for cats and small dogs. There is no well-defined quantity for each species, let alone for each breed. The principle, however, remains the same: to compare the blood glucose response between a food being tested and a reference food. As we have said, the quantity tested is ultimately of little importance since it is a comparison; the only requirement is to match the carbohydrate content of the food being tested and the reference food. For diabetic animals, the benefit of a low-glycemic-index food is even greater. Every meal causes a rise in blood glucose. In the case of diabetes, to counteract this rise, insulin injections administered by the owner are necessary. This forms the basis of diabetes treatment, in conjunction with weight loss if the animal is obese, and a specific diet. Currently, a diet rich in complex carbohydrates (starch and dietary fiber providing 50 to 55% of energy), free of simple sugars, low in fat (less than 20% of energy), and moderate in protein (14 to 30% of energy) is recommended for dogs [3] . The aim of such a diet is to limit postprandial hyperglycemia. As in humans, a low-glycemic-index food results in a more modest rise in blood glucose than a high-glycemic-index food. It has been shown that a food rich in insoluble fiber, and therefore theoretically low in glycemic index, improves blood glucose control in dogs [4] [5] and cats [6] . A moderate rise in blood glucose is more easily managed with insulin. Regardless of the type of insulin used, the required doses will be lower, and therefore the side effects will be fewer. Thus, the risk of hypoglycemia is significantly reduced, and the risk of developing insulin resistance is lower. In dogs, the benefit of a low glycemic index diet lies in a reduction of fructosamines, glycated hemoglobin, and HDL and LDL (Low Density Lipoprotein), the former being markers of frequent hyperglycemia [7] . This is true in dogs, due to their eating habits (1 to 2 meals per day), but much less so in cats, which eat many small meals day and night, sometimes up to 20 in total. The rise in blood glucose is less pronounced after each meal because of the small amount ingested. It is therefore not certain that feeding a diabetic cat a low [8] glycemic index food brings about a notable improvement, and experiments will be needed to determine whether such a diet has a direct benefit in the management of feline diabetes.

Glycemic index and obesity in dogs and cats:

It has been shown that consuming high glycemic index foods induces an immediate hypersecretion of insulin and greater fat deposition after 4 weeks in rats [9] . Insulin sensitivity is not affected by such a diet over this period [10] , which is too short a time to assess the insulin resistance potentially triggered by high glycemic index foods. No studies have yet been conducted on this subject in domestic carnivores. As in humans, obesity in domestic carnivores is steadily increasing in industrialized countries. The stronger the emotional bond with the animal, the more likely it is to be fed in quantities exceeding normal amounts. Although animal and human obesity are often compared, far fewer correlations between obesity and disease have been established in domestic carnivores. However, many similarities exist between humans and dogs regarding the molecular mechanisms leading to the development of insulin resistance and dyslipidemia [11] . The general mechanisms appear similar, and it therefore seems reasonable to assume that the results obtained in humans concerning glycemic index and obesity are applicable to dogs with minimal adjustments. For cats, on the other hand, further experiments would be necessary because little data is available on the frequency and mechanisms of obesity in cats [12] .

The main pathologies resulting from obesity in animals are:

• Osteoarthritis, caused by excess weight, particularly on the hips. This is the condition most often linked to obesity.
• breathing difficulties, less related to discomfort due to weight than to the narrowing of the anatomical airways,
• a higher prevalence of infectious diseases,
• liver diseases such as lipidosis, particularly in cats,
• Feline urinary syndrome (FUS), with an enigmatic causal relationship,
• and finally, diabetes.

This list is not exhaustive, but it illustrates the problems caused by morbid overweight in animals. The treatment of obesity, that is, the reduction of body mass, can be approached in two ways: either by increasing energy expenditure through a resumption or increase in physical activity, or by reducing energy intake. In both cases, a complete clinical examination is an essential prerequisite, to which it is advisable to add blood and biochemical tests to rule out any other underlying cause of obesity, such as a thyroid hormone imbalance. Increasing energy expenditure is sometimes impossible, in the case of animals belonging to people who cannot provide them with sufficient physical exercise, or difficult in cats, which are sometimes averse to exercise.

Reduction in energy intake

Reducing energy intake can take two forms. One option is outright fasting, which, besides being ethically questionable and even more difficult for owners to accept, poses health risks to the animal. Indeed, in obese cats, hepatic lipidosis is often triggered by fasting, which will therefore indirectly lead to the animal's death. A more practical solution is to implement a reduced or "light" diet, meaning one with lower energy content. Veterinarians frequently encounter situations where such a diet is necessary. Reduced ("light") formulations generally simply contain less available energy. They differ from dietetic foods for obese animals, which are specifically formulated to provide adequate nutrition during a weight-loss phase. Measuring the glycemic index of these dietetic foods would be very beneficial. In fact, a food's low fat content does not necessarily mean its available energy is low. In humans, a food with a low glycemic index leads to a greater and longer-lasting feeling of satiety than a food with a high glycemic index [13] . In this case, the next meal is smaller or less frequent. If the same is true in animals, as one might expect, this would contribute to reducing energy intake, thus playing a more active role in obesity treatment. Mentioning the glycemic index could therefore be a valuable piece of information or even a selling point for dietetic foods. Ultimately, it would be useful for practitioners to know the glycemic index of the foods they prescribe for the treatment of obesity and diabetes, especially in dogs due to their eating habits. This would be valuable information for better assessing the expected benefits of a diet. Regarding homemade diets, the basic dietary rules for creating a balanced diet take precedence over everything else. Furthermore, measuring the glycemic index of a home-prepared meal is pointless, as the homeowner cannot standardize their preparation process. The glycemic index of the meal is therefore likely to vary from day to day. However, if possible, it would be advisable to create this diet using ingredients with a low glycemic index, for example, favoring brown rice over white rice, etc. The benefit of such a diet is uncertain, since it cannot be measured; but if such a meal were easily prepared in practice and compatible with good diabetes management, there would be no contraindication to its preparation.

Other diseases:

The glycemic index has diverse biological applications, and it may be worthwhile to study its effects in areas other than the management of obesity and diabetes. Let's return to the basic principle: a food with a low glycemic index causes a smaller but more sustained rise in blood glucose than a food with a high glycemic index. Conversely, a food with a high glycemic index causes a significant rise in blood glucose over a shorter period. In a healthy, properly fed cat, gluconeogenesis functions continuously at the body's maximum enzymatic capacity. Therefore, it cannot increase when the cat is under stress. However, hyperglycemia is common during stress, caused by insulin resistance due to an increase in circulating glucagon and corticosteroids. In the case of a hospitalized cat, stressed by both the hospitalization and its illness, the nutritional objective should be to ensure sufficient energy intake while avoiding exacerbating any existing hyperglycemia. Low glycemic index foods would therefore be a particularly interesting option in this case. Indeed, they provide the necessary energy to the animal, but over a longer period. The already high blood sugar level will rise less sharply and to a more limited extent. This would, to some extent, help to mitigate the effects of stress on the energy metabolism of the hospitalized cat. Any hospitalized cat could therefore be fed, if its health permits, with low glycemic index foods, provided it eats spontaneously. However, in the case of assisted enteral nutrition, the indication seems less clear. Indeed, low glycemic index foods, due to their high fiber content, are generally more viscous and less digestible than other foods. This could impede the flow of food through the feeding tube, obstruct it, or promote food adhesion and stagnation on its walls, etc. Foods specifically formulated for enteral nutrition are more appropriate, but it may be possible to develop a low-glycemic index food suitable for this purpose, if its real benefit is demonstrated. Low-glycemic index foods are therefore suitable for cases where a more gradual, sustained energy supply is desired. Each indication is determined by the veterinarian's judgment based on the specific characteristics of the animal and its condition.

Should high glycemic index foods be banned from the diet of domestic carnivores?

These foods are not harmful, and some of their characteristics can prove useful and compatible with daily veterinary practice. Chronic enteropathy of the large intestine due to bacterial overgrowth is a relatively common condition in veterinary medicine. The cause of this overgrowth is generally unknown, although intestinal stasis is frequently a determining factor. In young dogs, bacterial overgrowth typically manifests as chronic intermittent diarrhea, sometimes accompanied by weight loss or stunted growth. This overgrowth, which generally affects the entire colon and sometimes the small intestine, requires appropriate antibiotic treatment, ideally guided by an antibiogram. Indeed, the presence of an abnormal bacterial population in the small intestine interferes with the digestive process and deprives the body of nutrients, as the bacteria divert them for their own benefit. Competition for nutrient absorption, particularly carbohydrates, arises between the cells of the intestinal villi and bacteria. However, a high-glycemic-index food contains readily available, rapidly absorbed carbohydrates, making them less accessible to bacteria and thus creating a less favorable environment for their growth. Studies have shown that when dogs are fed rice (with a high glycemic index) instead of the grains (with a lower glycemic index) found in commercial dog food, carbohydrate digestibility is increased [14] . These carbohydrates, which cannot be digested by the dog itself, are sometimes fermented by the bacterial population, which thus acquires nutrients. Therefore, feeding a high-glycemic-index food results in a reduced availability of usable fiber for bacteria. This has not yet been validated by experiments but warrants further investigation. High glycemic index foods could therefore be indicated alongside appropriate antibiotic treatment and help improve the health of an animal suffering from chronic enteropathy. For the same reasons, after a relatively large small intestine enterectomy, the absorption surface area is reduced compared to a normal animal, and a food with rapidly assimilable energy and a high glycemic index seems more suitable.

Carbohydrates in sporting dogs

In the field of specific nutrition, for a sporting animal performing short but intense efforts, such as an agility dog ​​or a racing greyhound, it would be beneficial to distribute a high glycemic index food between half an hour and three-quarters of an hour before the start of the event, in order to provide a large amount of available energy over a short period. However, for a dog performing sustained exertion over time, such as a hunting dog, it seems more appropriate to provide a low-glycemic index food to ensure a long-lasting energy supply. Results obtained in humans indicate that athletes practicing endurance-based disciplines derive greater benefit from consuming low-glycemic index foods [15] . In summary, high-glycemic index foods could be beneficial when a short but significant carbohydrate absorption is desired, both for sporting animals and for animals with conditions that reduce intestinal absorption. Thus, knowing the glycemic index of a food provides the practicing veterinarian with a simple piece of information that translates concretely at the biological level. Depending on the desired effect, they could recommend a type of food suited to each case, taking into account the other properties of the food. It would be possible, for example, to develop a range of foods with varying glycemic index values. One could imagine a low-glycemic-index food containing little but high-quality protein for a hospitalized cat with kidney failure; or the same food with a high glycemic index for another cat with kidney failure but suffering from bacterial enteropathy. Without going so far as such costly specialization, knowing the glycemic index of a compound food would help guide veterinary prescriptions, particularly for diets prescribed for diabetes and obesity.

APPENDICES:

Excerpt from the website: What if I make homemade rations? I would like to understand the impact of food on my dog's body:

Rice

White rice is excellent in terms of digestibility and is also one of the least allergenic starches. Broken rice is simply pieces of broken rice. Puffed rice is even more digestible and doesn't require cooking. Wholegrain rice, on the other hand, contains wheat bran and therefore provides more fiber for the same amount of energy, which can be irritating to a dog's intestines. The amount of rice should not exceed half the amount of other starches. For example, you can give 50% white rice and 50% wholegrain rice.

Potatoes and sweet potatoes:

Potatoes and sweet potatoes require extra preparation as they need to be peeled and mashed. A good alternative is to use potato flakes.

Quinoa

Quinoa is a grain richer in calories, protein, fat, and minerals than other grains. When quinoa is cooked, the germ separates from the seed. It can be used occasionally in homemade meals.

But and oats

Oatmeal is rich in protein and iron, and it has a calming effect. Corn is good for the coat. It can be given fresh or in flake form. Corn flakes are already cooked; be sure to buy them plain and unsweetened. Polenta is a cornmeal.

Pasta and wheat: (caution: gluten)

Pasta is generally made from wheat flour, but other types of pasta containing vegetables or other non-allergenic grains are also available. Wheat contains gluten and can cause allergies in some dogs. Wheat semolina can also be used.

Too much or not enough

Starchy foods are useful but not essential in a dog's diet: there is no "minimum" as long as there is enough protein. Their use is primarily a way to reduce protein and fat intake in order to tailor rations to the needs of different dogs. Their quantity should remain small compared to other foods; in fact, it is the portion of starchy food that is reduced if the ration calculated by the veterinarian causes the dog to gain a little weight and needs to be readjusted. In excess, they can be poorly digested and lead to diarrhea and inflammation, in addition to increasing stool volume. The importance of cooking: Starchy foods must be cooked very thoroughly, almost as if pre-digested, thus transforming the starch into something usable by the dog's digestive system. The trick is simply to double the cooking time. To simplify recipes, rice or other starchy foods can be cooked at the same time as vegetables. There's no need to rinse the rice or pasta; simply drain it after cooking. One trick is to use puffed rice, which doesn't need to be cooked! It only needs enough moisture or the addition of hot water to crackle like the cereals of our childhood and make us think, "Mmm, your dog is going to love this!"

How to determine and calculate the impact of carbohydrates in the diet? (Excerpt from a website)

The glycemic index

Carbohydrates are classified according to their ability to trigger insulin production. The faster a sugar enters the bloodstream after ingestion, the more insulin is produced. Insulin is a hormone produced by the pancreas. It lowers blood sugar levels by:

	increase in sugar in adipose (fatty) cells and in muscle cells.
	decrease in the use of fats (lipids).
	increased production of reserve glycogen in the liver.

The glycemic index is 100 for glucose, 51 for pasta, 39 for apples and 29 for fructose.

Glycemic index for an equal amount of carbohydrates
Fast-acting sugars		Average Sugars		Slow-release sugars
glucose	100	sugar (sucrose)	65	wholemeal pasta	42
carrots	92	wholemeal bread	65	oranges, apples	40
Honey	88	brown rice	66	cooked chickpeas	35
corn flakes, mashed potatoes	80	bananas	62	lenses	30
white rice, bread	72	pasta	50	fructose	29
steamed potatoes	70	oat flakes	50	soybean sprouts	15

We note that:

	Simple sugars have a high glycemic index, with the exception of fructose, which, although rapidly assimilated, does not alter insulin production.
	Foods rich in fiber have a low glycemic index.
	Simple sugars taken at the end of a meal behave like slow-release sugars;
	Fruit juices have a higher glycemic index than the corresponding fruits;
	Mashed potatoes have a higher index than steamed potatoes.
	The glycemic index is modified by the method of preparation, the quantity ingested, the association with other foods, and the timing of ingestion during the meal.

Taking the glycemic index into account is important in the case of diabetes .

Carbohydrate content of some foods

(as a percentage of weight)

Foods containing fast-acting sugars	Carbohydrates
refined sugar	100
Honey	75
jam	70
dried fruit	60 to 70
chocolate	60
fresh fruit	10 to 20
sodas	10 to 20
freshly squeezed orange	10
skimmed milk	5
Foods composed of slow-release carbohydrates	Carbohydrates
raw rice	77
wheat rusks	75
dried beans	60
white bread	55