Pets and the Science of Aging

Filed Under: Dogs, Cats, General Care

Remember those not so distant days spent studying American history? It was always tough to keep all of the early explorers straight. It seems like they were always on the hunt for gold, with a few notable exceptions: Ponce de Leon trampled all over the state of Florida looking for what the Indians told him was the “Fountain of Youth.” Obviously that wasn’t the case, but today we may have the first nutritional supplements that just might help us keep a youthful appearance and vigor in the form of antioxidants.

Have you considered that “Old Age” is not a disease, but rather a reflection of the effects of time upon our physical, mental, and internal age? Each one of our organ systems degenerates or ages at a different rate, thus determining our “Biological Age.”

There are four general factors involved in aging that include: 1. The accumulation of toxic substances within the cells; 2. Cumulative cell damage resulting from ionizing irradiation, oxygen derived free radical-mediated damage, and/or environmental pollutants; 3. Immune mediated or pathology caused by a compromised immune system; and 4. Genetically preprogrammed cell death, which is specified by individual genes responsible for lifespan.    

In 1956, Denham Harmon first proposed the “Free-Radical Theory of Aging.” The theory, which has since been proven, states that the production of free radicals associated with aging or those produced from chronic inflammation can have devastating effects upon the body’s cells, cellular DNA, organelles within the cells, and the cell membranes. The accumulation of excess free radicals is also known as “oxidative stress.” Dietary or supplemental antioxidants can help decrease the cellular damage produced by these free radicals.

Antioxidants that can be supplemented by dietary means include vitamins E and C, zinc, omega-3 fatty acids, DHA (Docosahexaenoic Acid) and EPA (Eicosapentaenoic Acid), lipoic acid, L-carnitine, carotenoids, flavonoids, SAMe/SOD, and lutein. Each antioxidant has its own unique mechanism of action. It is generally accepted that an “antioxidant package” comprised of several different antioxidants is a superior supplemental strategy to picking or choosing only certain antioxidants to medicate with.

Vitamins E and C are both potent antioxidants and immune-enhancers. Vitamin C is required for the growth and repair of tissues, especially in the healing of wounds. Vitamin C is necessary to form collagen, which is an important protein necessary to make skin, scar tissue, tendons, ligaments, and blood vessels. Animals other than humans, monkeys, and guinea pigs will manufacture required amounts of vitamin C. People, monkeys, and guinea pigs, however, cannot manufacture their own Vitamin C and therefore require vitamin C from their diet. Vitamin E is also important in combating oxidative stress, which is involved in and responsible for chronic degenerative diseases including cancer and cardiovascular disease.

Omega-3 fatty acids are commonly found in fish, walnuts, leafy vegetables, flaxseeds, and hemp seeds. Omega-3 fatty acids are acted upon by an enzyme called “desaturase,” which converts it into DHA and EPA. Both DHA and EPA have anti-inflammatory and platelet inhibiting effects. Omega-3 fatty acids may also reduce pain by directly interacting with an ion channel found in neurons and in the brain that is involved in signaling inflammatory pain. In addition, these particular fatty acids may help modulate behavior. Ever wonder why some individuals are always in a bad mood? Maybe you should suggest they eat more “good fats.”

Alpha lipoic acid is a unique antioxidant that functions in water-soluble as well as fat-soluble environments. Lipoic acid increases the formation of glutathione (which is a potent antioxidant) and is naturally found in small amounts in spinach, broccoli, peas, Brewer’s yeast, Brussels sprouts, rice bran, and organ meats. Most dietary supplements must be manufactured since naturally occurring lipoic acid is found in nature at such low levels.

Thanks to its water-soluble characteristics, alpha lipoic acid is commonly used in the treatment of peripheral neuropathy. Peripheral neuropathy results in the loss of sensation, numbness, or itching of the extremities following such conditions as diabetes, thyroid or Lyme disease, secondary to their effects on nerve tissue.

L-carnitine or carnitines are naturally occurring amino acids that play significant roles in fat metabolism. These proteins are directly responsible for the transport of fatty acids directly into the mitochondria. Mitochondria are the metabolic furnace, or energy producer, for each individual cell.

Carnitines are synthesized in the liver and kidneys from the amino acids lysine and methionine. Up to 98% of all carnitines are found in muscle tissue. L-carnitines are found naturally in red meat, dairy products, avocados, and tempeh (fermented soybean cake).

Carnitines are used by those wishing to increase endurance and improve fitness. The use of carnitines allows the body to burn more fat while having a sparing effect on the body stores of glycogen (glucose packaged for emergency usage). These amino acids are also believed to be helpful in the treatment of diabetes, chronic fatigue, kidney disease, and liver disease.

Most individuals will obtain sufficient levels from carnitines in their diet, rendering supplementation unnecessary. When carnitine is provided at excessive levels, the excess is simply excreted from the body.

Ever wonder what causes those vivid orange, yellow, and green colors of our fruits and vegetables? The vivid color is due to carotenoids, a group of naturally occurring pigments found in carrots, sweet potatoes, spinach, kale, collard greens, and tomatoes. Carotenoids not only impart color to our food but are potent antioxidants as well. Beta-carotene, one such carotenoid, is also believed to be an important immune system enhancer. Carotenoids are also considered to be very important in cell-to-cell communication, and are thereby believed to function in the prevention of cancer.

Flavonoids are compounds that are naturally found in certain fruits, vegetables, and in particular beverages such as beer because of hops. Flavonoids are polyphenolic compounds that have potent antioxidant activities. Flavonoids also prevent LDL, or low-density lipoprotein, from being oxidized and forming atherosclerotic plaques which are involved in heart attacks and strokes.

SAMe (S-adenosylmethionine) is manufactured from methionine, which is an amino acid found in protein-rich foods and is necessary for a body process termed “methylation.” When a SAMe molecule loses its methyl group it becomes homocysteine, which is an extremely toxic substance if it is allowed to build up within individual cells. High levels of homocysteine have been linked with certain birth defects such as spina bifida or with heart disease and stroke. With the help of B6, B12, and folic acid, homocysteine is converted to glutathione or it is remethylated back into methionine.

SAMe is believed to fight depression and relieve symptoms of arthritis, where it may be as effective as a nonsteroidal anti-inflammatory.

Lutein is a another naturally occurring antioxidant. Found in carrots, squash, and additional yellow/orange vegetables, as well as in leafy green vegetables such as spinach. Lutein slows the development of macular degeneration and cataracts.

Have we found the fountain of youth? Probably not quite yet! A good combination of antioxidants may, however, be able to slow down the aging of our pets and make them more comfortable in their senior years.


“Nutritional Supplements.” Antech Diagnostics. August 2008. P. 1-2.

Fortney, William. “The Diagnosis and Management of Common Problems of Aging in Dogs and Cats.” Ralph Lee’s Great Smokies Veterinary Conference: Notes. 2009. Pp. 427-431.

Robinson, Narda. “Fatty Acids Play Key Role in Overall Health.”  Veterinary Practice News. January 2008. Pp. 34.

Robinson, Narda. “How Fatty Acids Fight Inflammation.”  Veterinary Practice News. May 2008. P. 22.

Topics: aging, antioxidants, vitamins

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