Dog Nutrition
Balanced Nutrition
Mother Nature, created the nutrient composition of the whole animal carcass to perfectly meet the nutritional needs of the carnivore. Prey and predator are similar in terms of elemental constituents, so they are nutritionally exchangeable. The body composition of the dog gives an indication of the type of diet needed for physical maintenance: water 42-67%, protein 16% -60%, fat 10-41%, minerals 3.5% and carbohydrates 1.7%.
A raw adult White Tailed Deer comprises of approximately 47% protein and 41% fat. A wild canine will usually consume this prey in its entirety, including the bones. Bones in the White-Tailed Deer provide a 2:1 ratio of calcium to phosphorus for the maintenance of the canine’s skeleton. Besides, calcium and phosphorus, a White-Tailed Deer supplies the essential vitamins and minerals as well as numerous antioxidants. Dogs are opportunistic eaters and have developed characteristics that permit digestion and usage of a varied diet.
Protein
Proteins are made from amino acids. There are 23 naturally occurring amino acids and as many of these may be joined in any sequence, there is an almost infinite variety of proteins possible. Amino acids may be divided into two groups – essential and non-essential.
Essential amino acids are those which must be present in the diet as the body is unable to make them at a rate sufficient to meet the dog’s requirements. The actual amino acids counted as essential varies from species to species. There are ten amino acids which are essential for the dog: arginine, histidine, Isoleucine, lysine, methionine, phenylalanine, Threonine, tryptophan and valine.
Taurine is considered essential for cats; however, dogs have no essential dietary taurine requirement because they have the metabolic capacity to synthesize it from sulfur amino acids such as cystine and methionine in raw animal tissue. Research indicates that it may be “conditionally” essential. In one study researchers showed that feeding a high- fat food (24%DM) significantly reduced plasma taurine concentrations, with values becoming marginally deficient.
Studies in various species have shown taurine to be essential in certain aspects of development, and have demonstrated that low levels of taurine are associated with various pathological lesions, including cardiomyopathy, retinal degeneration, and growth retardation, especially if deficiency occurs during development.
Investigations to find out how diet composition affects taurine metabolism in dogs, and how taurine deficiency may play a role in the development of Dilated Cardiomyopathy (DCM), particularly in large-breed dogs are underway. When DCM has occurred there has been a reversal in the symptoms when taurine is administered. Some companies have begun adding taurine to their dog foods since dietary taurine is destroyed when meat products undergo heating. Unlike true amino acids, taurine is not incorporated into proteins. It is one of the most abundant free amino acids in many animal tissues, including skeletal and cardiac muscle, and the brain.
Non-essential amino acids can be manufactured by the body from other amino acids, but their inclusion in the diet means that a lesser quantity of essential amino acids is required. Since cell replacement and repair is an ongoing feature of living creatures, essential amino acids need to be present in the diet on a daily basis.
Proteins occur in both animals and plants. The quality or biological value is important as the higher values will be best utilized by the body leaving few waste residues to be excreted. Protein is required for tissue building and growth, the structural components of cells, movement of muscle contraction. Protein provides strength with flexibility in ligaments, tendons, and cartilage and transports nutrients. Protein deficiency can interfere with any body systems, leading to poor growth or loss of body weight, poor coat condition and impaired immunity among other problems. If more protein is consumed than is needed for growth, repair, and other functions, the excess is used for energy or stored as fat. This leaves wastes, which are converted to urea by the liver and excreted primarily through the kidney. Energy is produced less efficiently from protein than from fat or carbohydrate.
The quality or “biological value” of a nutrient is the amount of that nutrient absorbed and utilized by the body. It is expressed as a percentage and can be applied to all nutrients but is particularly used in reference to protein quality. The biological value of a protein is a measure of how closely the proportions of essential amino acids match the requirements of the animal. High biological value proteins are highly digestible and leave fewer waste products to be excreted from the body. Animal proteins are of higher biological value than plant proteins.
Fats
Evolution has made fat the “fuel” of choice for the canine species. It provides approximately twice the energy provided by protein and carbohydrate. The digestion of fat and protein in the dog’s gut is extremely efficient. Fat carries the fat-soluble vitamins A, D, E and K. Fat contains essential fatty acids (EFAs) that dogs cannot make, but are vital for health. Dogs have an essential requirement for one particular fatty acid, omega-6 or linoleic acid. It helps regulate the blood flow to body tissues; aids in clotting after an injury and is required for normal reproduction. It helps a dog's immune system respond to injury and infection, and help a normal, healthy pet maintain a handsome coat and healthy skin.
Omega-3 fatty acids are also important for maintaining healthy skin and coat. These fatty acids are found in high concentrations in fish oils and certain plants. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are provided by including fish such as salmon, herring, mackerel, anchovies, and sardines or fish oil in the diet. Eicosapentaenoic acid (EPA) is not currently considered essential in companion animal nutrition. Research suggests that this class of fatty acids may benefit pets during certain life stages or when suffering from certain diseases. Omega 3 fats play an important role in the production of powerful hormone-like substances called prostaglandins. Prostaglandins help regulate many important physiological functions including blood pressure, blood clotting, nerve transmission, the inflammatory and allergic responses, the functions of the kidneys and gastrointestinal tract, and the production of other hormones.
Docosahexaenoic acid (DHA) is the most abundant fatty acid in the dam's milk and is important for normal eye and brain development. Experimental animals whose diets are low in DHA have been found to have smaller brains, reduced brain development, diminished visual acuity and delayed central nervous system development. DHA is found in animal organs such as brain and liver, and cold water fish.
Carbohydrates
Dogs do not have an essential requirement for carbohydrates. In their natural habitat, dogs consume prey that is high in protein with moderate amounts of fat and minimal amounts of carbohydrate (1-2%) are utilized in the diet (soluble or insoluble fiber). Although dogs can use carbohydrates as a source of energy, the limitations of substituting animal-origin nutrients with plant-origin nutrients in dog foods are being increasingly realized. Recent research has shown that high-carbohydrate diets are responsible for many cases of canine diabetes. In fact, not only diabetes but many serious health problems in dogs have a dietary factor. Some are caused by diet, and all are affected by it. Diet-related diseases include obesity, chronic vomiting, pancreatitis, arthritis, heart disease, allergies, inflammatory bowel disease, urinary tract disease, hyperthyroidism, skin and coat problems, and cancer.
Dogs lack salivary amylase, the enzyme responsible for initiating carbohydrate digestion. Many pet owners and pet food manufacturers insist on adding vegetables or grains to a dog's diet claiming that they would eat them along with the stomach and intestines of their prey. However, this does not take into account that the amount of vegetable matter in small prey is small and more often than not, the stomach and the intestines are not eaten from large herbivorous prey.
Dogs do have a metabolic requirement for glucose. This requirement can be supplied either through endogenous synthesis (endogenous synthesis refers to the synthesis of a compound by the body) of glucose or from carbohydrate food sources. Metabolic pathways in the liver and kidney use other nutrients to produce glucose through a process called gluconeogenesis. This glucose is then released into the bloodstream to be carried to the body’s tissues. The dog can maintain normal blood glucose levels and health even when fed a carbohydrate-free diet.
Fiber
There are two forms of fiber – insoluble and soluble. Soluble fiber keeps food in the stomach longer whereas insoluble fiber stimulates the bowel. Fiber is a natural part of the dogs’ diet, coming from the fur, feathers, bones, cartilage and viscera of its prey. A variety of fiber sources such as beet pulp, chicory, rice bran, and psyllium are some of the fiber sources commonly used in prepared commercial cat diets, all poor substitutes when compared to nature’s model.
Vitamins
Vitamins are complex organic substances required in very small amounts to maintain growth, health, and survival of living creatures. Plants can manufacture the vitamins they require but animals, on the whole, cannot, and therefore require them as an essential part of the diet. The dietary source may be in the form of a precursor from which the animal is able to manufacture the vitamin. Some vitamins are produced by bacteria within the large intestine which may then be utilized by the dog.
There are 13 major vitamins, A, B-complex, C, D, E, and K, and these take part in many of the chemical reactions of metabolism. Vitamins act as enzymes, coenzymes (molecules that attach to a protein to form active enzymes) and enzyme precursors. Since most metabolic reactions are but one part of a sequence of reactions, slowing any one reaction through the absence of a vitamin can have widespread effects on the body. A lack or poor absorption of a vitamin causes deficiency and an excess can cause hypervitaminosis.
Vitamin A
The water-soluble vitamins include vitamin C and the B-complex family and play many roles in health and metabolism. Dogs require B vitamins in their diet. As its name implies, vitamin B complex is a combination or mixture of eight essential vitamins. Although each is chemically distinct, the B vitamins coexist in many of the same foods and often work together to bolster metabolism, maintain healthy skin and muscle tone, enhance immune and nervous system function, and promote cell growth and division - including that of the red blood cells that help prevent anemia. Together they also combat stress, depression, and cardiovascular disease. B vitamins, which are water soluble, are dispersed throughout the body and must be replenished daily with any excess excreted in the urine. B complex vitamins are plentiful in meat and organs.
B Vitamins
The B-complex vitamins are actually a group of eight vitamins, which include thiamine (B1), riboflavin (B2), niacin (B3), pyridoxine (B6), folic acid (B9), cyanocobalamin (B12), pantothenic acid and biotin. These vitamins are essential for: the breakdown of fats and proteins (which aids the normal functioning of the nervous system), muscle tone in the stomach and intestinal tract, skin, hair, eyes, mouth and liver function. The B vitamins are most effective for health when consumed as a complex, rather than individually.
Vitamin C
Dogs do not have an essential requirement for a dietary source of vitamin C. Under normal conditions, they synthesize vitamin C in their liver which produces the active enzyme L-gulonolactone oxidase, the last of the chain of four enzymes which synthesize ascorbic acid. There is no purpose in supplementing the dog’s diet unless there is a high metabolic need or inadequate synthesis. It is important to note that dietary vitamin C in natural products has a distinct advantage over supplemental synthetic vitamin C, e.g. in supplemental form since food sources also provide a number of other important micronutrients, bioflavonoids, carotenoids, and pectin. Vitamin C, in the form of ascorbic acid and dehydroascorbic acid, is widely available in foods of both plant and animal origin. Fruits, vegetables, and organ meats, e.g. liver, kidney, thymus, spleen and lungs, are generally the best sources.
Vitamin D
A dog's body has two sources of Vitamin D. It is consumed in the diet from organ meats, fish liver, and egg yolks, and is also manufactured in the skin by the sun. Ultraviolet radiation from the sun is important to convert Vitamin D precursors into the active D form. This conversion takes place in the outer skin layers. Whether a dog ingests vitamin D in their diet from plants or animal tissue, it goes through two organs before it's activated; the first is the liver and then it goes from the liver to the kidney, where it's activated to 1-25 dihydroxy vitamin D. How much sunlight does a dog need for D synthesis? That depends on the time of day, season of the year, where it lives, its age, and how much pigmentation occurs in its skin. About 10-15 minutes of sunshine daily is usually enough for the dog’s body to make vitamin D providing all the factors previously mentioned are in place.
Vitamin D is needed for calcium and phosphorus absorption and is essential for strong bones, healthy teeth, nerve function and normal growth. Low levels of Vitamin D will cause a bone demineralization referred to as rickets. Vitamin D toxicities are extremely rare. A dog fed Vitamin D in excess could have abnormal amounts of calcium deposited within the heart, various muscles, and other soft tissues.
Vitamin E
Vitamin E is a fat-soluble vitamin. Vitamin E is highly concentrated in meats such as liver and fat. Vitamin E plays a role in the formation of cell membranes, cell respiration, and in the metabolism of fats. It is an antioxidant and protects various hormones from oxidation.
Deficiencies of Vitamin E cause cell damage and death in skeletal muscle, heart, testes, liver, and nerves. It is essential in keeping the cells of these organs alive and functioning. Vitamin E deficiencies have been well documented in both dogs and cats. The 'Brown Bowel Syndrome' is the condition usually used to describe a dog or cat suffering from inadequate Vitamin E. These animals have affected bowels which ulcerate, hemorrhage, and degenerate. In addition, the cells of the eyes and testes can also be affected. There are no known Vitamin E toxicities in dogs. When administered at high levels, no interruptions of bodily function were demonstrated.
Vitamin K
Vitamin K is another fat soluble vitamin. Vitamin K exists in three forms. Vitamin K1 is found in green plants, vitamin K2 can be synthesized by the bacteria in the intestine and vitamin K3, also known as menadione, is a synthetic precursor of the others. Since the bacteria in the intestine can manufacture Vitamin K, it is not needed in high levels in food supplements.
Vitamin K is needed for blood clotting and plays an important role in bone formation. The actual dietary requirement for Vitamin K is uncertain. Since bacteria within the intestines manufacture Vitamin K, the exact amounts produced are unknown. Dietary Vitamin K is found in liver, egg yolks, and dark green leafy plants and vegetables.
Minerals
More than 18 mineral elements are believed to be essential for mammals. There are seven macrominerals: calcium, phosphorus, sodium, magnesium, potassium, chloride, and sulfur. There are at least 11 microminerals or trace elements: iron, zinc, copper, iodine, selenium, cobalt, molybdenum, fluorine, boron, and chromium.
Minerals are inorganic elements that are vital to life and are components of muscles, tissues, and bones. Minerals play an important role in sustaining and regulating various chemical reactions and bodily functions, including acid-base balance, oxygen transport, nerve conduction and immunological responses. Some minerals act as antioxidants, which may help prevent diseases that are caused by the damaging effects of free radicals (i.e., autoimmune disease and diabetes). Various factors can interfere with mineral absorption and possibly result in a deficiency of that mineral, including aging, pregnancy, stress, disease and other nutrients or medications. Mineral composition - specifically the large particle size of many minerals - also may cause inadequate absorption in the gastrointestinal tract.
Whether a mineral is considered essential or not is based on its nutritional benefits. An element may be considered nutritionally beneficial if a low intake of that element has detrimental consequences (i.e., signs of deficiency).With a move toward disease prevention, an element also may be considered nutritionally beneficial if it has been found to reduce the risks of chronic diseases. Therefore, in reviewing minerals it is important to consider the primary goal of preventing nutrient deficiencies, as well as the secondary goal of reducing the risk of chronic diseases.
The Major Minerals
Calcium
Calcium is the most common mineral found in the dog’s body. Calcium is found in bones and teeth, and about 1 percent is present in the blood, muscles, and tissues. Functions of calcium include maintaining skeletal structure, mediating the constriction and dilation of blood vessels, conducting nerve impulses, muscle contraction and activating the blood-clotting cascade. Consequences of calcium deficiency include nutritional secondary hyperparathyroidism; loss of bone mineral content, which can lead to collapse and curvature of lumbar vertebrae and pelvic bones; bone pain, which can progress to pathological fractures.
There is a balance and movement between calcium in the bloodstream and calcium in the bone. When there is a deficiency of calcium in the blood, the body draws it out of the bone, causing the bone to be brittle, weakened and at risk for fractures. Another mechanism in which bone becomes weakened is through the remodeling process. Bone continuously is broken down (resorption) and replaced with new bone (formation). When bone resorption exceeds bone formation, bones become frail and weakened, increasing the risk of fractures and bone pain.
Phosphorus
Phosphorus is the second most essential mineral found in the body. It is a component of bone, and approximately 85 percent of the body’s phosphate is present in the bone in the form of calcium phosphate. The remaining percentage is present in the muscle and other soft tissues. Phosphorus is responsible for maintaining acid-base balance, oxygen delivery, energy production, kidney function and heart muscle contraction. Symptoms of low blood phosphorus levels (hypophosphatemia) include anemia, muscle weakness, bone pain and numbness of the extremities.
Magnesium
Approximately 60 percent of magnesium in the body is present in bones and the skeleton, and the remaining is found in the muscle and in other tissues that are metabolically active including the brain, heart, liver, and kidney. Magnesium plays a role in bone growth, muscle relaxation, cellular energy production, conduction of nerve impulses and normal heart rhythm. Although magnesium deficiency is rare, certain conditions (i.e. gastrointestinal disorders, renal disorders and old age) can lead to depletion of magnesium.
Potassium
Potassium is an electrolyte responsible for controlling nerve impulse conduction, muscle contraction and heart function. Potassium is found in the muscle, kidney, and liver. Signs of deficiencies include anorexia; retarded growth; neurological disorders, including ataxia and severe muscle weakness.
Chloride
Chloride is an electrolyte present in the highest concentrations in cerebrospinal fluid and the gastrointestinal tract. It is responsible for controlling water and acid-base balance in the body. Sodium and potassium are other electrolytes that work with chloride in maintaining that balance. Additional functions of chloride include stimulating the liver to filter wastes, hair coat, and teeth growth and producing the stomach acid necessary for digestion. Chloride deficiency may be caused by continuous vomiting and diarrhea or prolonged illness. Those conditions could lead to an acid-base imbalance in the body, which may present as nausea, vomiting, confusion and weakness.
Sodium
Sodium, an electrolyte found in the dog’s body, is an essential mineral, which is consumed as sodium chloride—otherwise known as table salt. Similar to potassium and chloride, sodium is responsible for conduction of nerve impulses, muscle contraction, cardiac function and maintaining blood pressure. Initial symptoms of sodium deficiency include vomiting, muscle cramps, and confusion.
Sulfur
Sulfur is concentrated in muscles, skin and bones and aids in the secretion of bile from the liver, removing potentially toxic substances (i.e., cadmium, copper, mercury, arsenic, lead, and aluminum) from the body and making collagen.
The Trace Minerals
Arsenic
Typically known as a toxic or poisonous element, arsenic has been identified as an essential trace mineral. Arsenic is believed to be involved in the metabolism of amino acids in the body, as well as other enzyme reactions.
Boron
The potential benefits of boron as an essential trace mineral only recently have been recognized. Boron aids in vitamin D metabolism, absorption, and utilization of calcium and development and maintenance of bone. It also promotes normal growth and development.
Chromium
The primary role of chromium as an essential trace mineral is in the metabolism of glucose and enhancing the response of insulin receptors to insulin. The liver is considered to be rich in chromium.
Copper
Copper’s primary role is in the synthesis and use of hemoglobin, as well as the storage and metabolism of iron, maintenance of bone, strengthening of connective tissues (especially in the heart), and enhancement of the immune system, skin pigmentation, and production of neurotransmitters. Although copper deficiency is uncommon, the most common sign is anemia, in addition to low white blood cell count, loss of skin pigmentation, impaired growth, cardiovascular abnormalities, reduced weight gain and longer time to conceive.
Fluoride
Approximately 95 percent to 99 percent of the body’s total fluoride is present in bones and teeth. Calcium by itself won’t build a molecule of bone. To use calcium, the body has to have adequate supplies of at least 9 other minerals, and fluoride is one of those minerals.
Iodine
Iodine is an essential mineral required in small amounts for the synthesis of thyroid hormones—thyroxine (T4) and triiodothyronine (T3)—that regulate growth and development, muscle function and functioning of the nervous and circulatory system. Approximately 75 percent of the body’s iodine is found in the thyroid gland, and the remaining iodine is distributed throughout the body. Iodine deficiency results in hypothyroidism and symptoms include lethargy, fatigue, sensitivity to cold, weight gain and dry skin and hair.
Iron
The two main sources of iron in the body, hemoglobin, and myoglobin, are responsible for the storage and delivery of oxygen. The remaining iron is stored in the muscles, heart, liver, spleen and bone marrow. Iron deficiency occurs in various stages, beginning with depletion of iron stores and developing to decreased red blood cell formation and, ultimately, reduced hemoglobin production (iron deficiency anemia). Iron deficiency anemia is characterized by symptoms of fatigue, increased heart rate, rapid breathing, and increased susceptibility to infections.
Manganese
Manganese is required by the body in small amounts for various enzyme reactions, which play a role in the breakdown of fats, protein, and carbohydrates, strengthening of bone, nerve transmission, reproductive processes and the production of collagen. Although rarely seen, signs of manganese deficiency include impaired growth and reproductive function, impaired glucose tolerance, possible neurological disorders (i.e., seizures) and altered lipid metabolism.
Molybdenum
Adequate levels of molybdenum are required for various enzyme processes (i.e., protein formation, carbohydrate metabolism and utilization of iron), fetal development and formation of bones and teeth. Deficiency of molybdenum is extremely rare because the dog’s typical diet provides enough of this trace mineral to perform the necessary functions.
Nickel
Studies have yet to determine an exact function of nickel in the body, and, therefore, a dietary reference intake has not been established. Highest concentrations of nickel are found in the thyroid gland, adrenal glands, and the lungs. Nickel may play a role in hormone production and activation of enzymes; with most of the information available from animal studies. Nickel deficiency has been linked to abnormal bone growth, poor absorption of iron and altered metabolism of calcium and vitamin B12.
Selenium
Selenium works as an antioxidant, along with vitamin E, to prevent body tissues from the damaging effects of free radicals. Highest selenium concentrations are present in the kidneys, liver, spleen, pancreas and testes. Selenium is required for normal growth, development and thyroid function. The level of selenium in meat and organs may vary depending on the selenium content of the soil, the feedstuffs grown on that soil, and whether the feed animal has been supplemented with selenium. As a result, the actual contribution of selenium to the diet may be variable.
Silicon
From animal studies, it appears that silicon plays a role in the formation of collagen, cartilage, and bone. Connective tissue and bone disorders are the most common signs of deficiency.
Vanadium
Vanadium is involved in a number of enzyme reactions and is most known for its ability to mimic the effects of insulin. The highest concentrations of vanadium in the body are present in the kidneys, spleen, liver, bone, testes and lungs. Vanadium may play a role in thyroid hormone metabolism and may have potential hypoglycemic and lipid-lowering effects. In animals, deficiency primarily caused decreased growth and thyroid function.
Zinc
Zinc is found in high concentrations in the eyes, brain, liver, kidneys and bones. Zinc is essential for immune system function, neurological responses (taste and smell sensations), reproductive health, wound healing and growth. Early signs of zinc deficiency include poor appetite, weight loss and slow healing of wounds developing to severe symptoms, such as hair loss, diarrhea, immunosuppression, reduced growth, impaired taste and impaired vision.
Other Trace Minerals
Although other trace minerals (i.e., aluminum, bromine, cadmium, cobalt, germanium, lead, lithium, rubidium, and tin) are present in small amounts in various tissues, there is limited evidence of their uses in the prevention or treatment of chronic disease.
Antioxidants and Zoochemicals
The use of oxygen in the body's normal processes creates chemicals known as free radicals. These have unpaired electrons and so they try to steal them from other molecules. These attacks damage the body's cells - a process called oxidation. In much the same way that air turns a cut apple brown, so oxidation damages the cell membranes, the genetic material in cells (DNA), fatty acids and other body structures.
Free radicals can affect the rate at which the body ages, start cancers by damaging the DNA in cells, increase heart disease, produce cataracts and encourage degeneration of the lens of the eye that ultimately leads to blindness and contributes to inflammation of the joints, as in arthritis. Antioxidants (AO) come to the rescue and neutralize free radicals. Although the body produces its own antioxidants to deal with free radicals produced each day as part of normal oxidation in the cells, an overload may leave the body's system unable to cope.
Early research centered on the antioxidant vitamins A, C and E also known as the ‘ACE’ vitamins and minerals such as copper, selenium, iron, manganese, and zinc. But in the last few years, researchers have discovered many, many more naturally occurring anti-oxidants which are not strictly nutrients from plants but “zoochemicals” derived from animals. Meat, organs, and fat found in the animal carcass include antioxidants such as carnosine, glutathione, CoQ10, L-Carnitine, alpha-lipoic acid and conjugated linoleic acid (CLA).
Carnosine
Carnosine is a small molecule composed of the amino acids, histidine, and alanine. It is found in relatively high concentrations in several body tissues; most notably in skeletal muscle, heart muscle, and brain. The exact biological role of carnosine is not completely understood, but numerous animal studies have demonstrated that it possesses strong and specific antioxidant properties, protects against radiation damage, contributes to the function of the heart, and wound healing. Carnosine has been suggested to be the water-soluble counterpart to vitamin E in protecting cell membranes from oxidative damage. Other suggested roles for carnosine include actions as a neurotransmitter (chemical messenger in the nervous system), modulator of enzyme activities, and chelator of heavy metals (i.e., a substance that binds heavy metals, possibly reducing their toxicity).
Alpha-Lipoic Acid
Alpha lipoic acid (ALA) is a sulphur-containing antioxidant, which occurs naturally, in small amounts, in muscle tissue (meat), kidney, and heart. Alpha lipoic acid (ALA) is readily soluble in water and fat, enabling it to exert an antioxidant effect in almost any part of the body, including the brain. At the cellular level, alpha lipoic acid (ALA) can act both as an antioxidant, capable of recycling other antioxidant nutrients such as vitamin C and vitamin E, and as a coenzyme for key metabolic enzymes involved in energy production. In addition to its role as an antioxidant, alpha lipoic acid (ALA) also raises the levels within cells of a substance called glutathione.
Glutathione
Due to its antioxidant properties, glutathione participates in a process which cells use to break down highly toxic peroxide and other high-energy, oxygen-rich compounds, in turn preventing them from destroying cell membranes, genetic materials (eg. DNA), and other cell constituents. Glutathione is also involved in repair of damaged DNA. It can bind carcinogens in the body, aiding in their removal via the urine or feces. It plays a role in immune function and can recycle vitamins C and E back to their active forms. Fresh muscle meat is an especially rich source.
Coenzyme Q10
Coenzyme Q10, or simply CoQ10 is a fat-soluble vitamin-like substance present in every cell of the body and serves as a coenzyme for several of the key enzymatic steps in the production of energy within the cell. It also functions as an antioxidant. It is naturally present in small amounts in a wide variety of foods but is particularly high in organ meats such as heart, liver, and kidney. CoQ10 is also synthesized in all tissues and in healthy individuals normal levels are maintained both by CoQ10 intake and by the body's synthesis of CoQ10.
L-Carnitine
L-Carnitine is a water-soluble vitamin known as vitamin BT. Because of the close structural sameness, it is often classed with amino acids. L-Carnitine is synthesized from the essential amino acids lysine and methionine, but enough vitamin B1 (thiamine) and B6 (pyridoxine) must be available. Unlike a true amino acid, it is not used in protein synthesis or as neurotransmitter, but is used for long-chain fatty acid transport and is required for entry of these long-chain fatty acids into the mitochondria of the cell, as well as for the removal of short-chain organic acids from the mitochondria, which frees the intra-mitochondrial coenzyme. It is therefore important for the energy supply within the cell, as well as muscles, and it assists in preventing fatty build-up in areas such as the heart, liver, and skeletal muscles.
Supplemental L-carnitine has been found to be beneficial for dogs with certain cardiac diseases such as decreased cardiac arrhythmia and to improve heart rate. It is also recommended for weight loss in obese dogs. Until recently, pet food companies paid little attention to L-carnitine in commercial diets. Because L-carnitine is sensitive to heat, losses can occur quickly during the processing of dry and canned pet foods. Therefore, it is becoming increasingly common as an additive in pet diets. However, L-carnitine has always been present in the carnivore’s natural diet, mainly in muscle tissue (meat) and liver.
Conjugated Linoleic Acid (CLA)
"CLA" stands for "conjugated linoleic acid" - a fatty acid identified in the 1970s by Dr. Michael Pariza, researcher, and director of the Food Research Institute at the University of Wisconsin, Madison. Pariza had been investigating the potential for carcinogenic effects in ground beef when he instead discovered a compound that could block the growth of tissues that support cancer. The active compound was identified as CLA - a form of linoleic acid with a differing arrangement of bonds within the molecule - hence the term "conjugated." Preliminary research suggests that CLA may not only suppress cancer cell development, but may also help reduce the risk of heart disease, boost the immune system, and help build lean muscles in animals. CLA is a naturally occurring substance in the guts of ruminant or cud-chewing animals like cows, and is present in fats in the meat of animals, specifically those that are grass-fed.
Nutrient Synergy
Nutrients never occur as isolates in natural foods. They are integrally related with many other natural molecules that are required for their absorption, assimilation, and non-toxicity. Most often, supplemental vitamins, minerals, and antioxidants are only a part of the whole nutrient complex. Isolated and synthetic nutrients are unnatural, usually poorly absorbed, and missing known and unknown co-factor nutrients. Although some isolated or synthetic nutrients can and do have some benefit, they are a vastly inferior way to obtain nutrients. In order for the body to absorb and utilize a synthetic or isolated nutrient, it must reform them into organic complexes (as they are in whole foods). Only a small percentage is able to be re-formed into absorbable, usable matter. The remaining unusable portion either, at best, settles out in the tissues as harmful deposits, or taxes the liver and kidneys before it is excreted in the urine.
If an isolated or synthetic nutrient is an antioxidant, it may actually weaken the body's immune system. The body's white blood cells use free radicals to destroy foreign bacteria. Isolated or synthetic antioxidants may weaken the body's ability to do so. They can also interfere with the body's use of oxygen. Antioxidants in whole foods (in addition to being much more effective), do not interfere with the body's ability to use free radicals constructively or it's ability to use oxygen (they enhance both). Despite modern advances, the best source of nutrients, by far, is natural food!