Physiological condition, rather than chronological age, determines whether a dog is mature. Aging begins when the body's systems start to slow down, when cells deteriorate faster than the body can repair them. Though large breeds tend to age faster than smaller breeds, the mature years generally begin at around 7 years (5 years for large breeds). If you feed your dog a diet designed to address the nutritional needs of his age, you can best maintain his overall health and well-being.
As your dog ages, it is important to detect and address with his veterinarian the telltale signs of aging or disease: a dull, dry coat and flaky skin, joint stiffness, energy loss, weight gain, increased water intake, digestive problems, and frequent constipation. These signs, among others, may be caused either by normal wear-and-tear or perhaps by the onset of disease. In any case, detecting and addressing them early may give your dog a greater chance to stay active and healthy.
When and how your dog responds to the aging process has a lot to do with genetics and environment, but nutrition plays an equally important role. The quality of food and its ability to maintain and nourish your dog's cells can help promote a long, healthy life.
As your dog ages and his systems become less efficient, he relies increasingly on the food you provide to make up for his body's shortfalls. According to Michael Hayek, PhD, an IAMS research nutritionist who specializes in geriatric nutrition, 'Aging dogs need the same nutrients as younger dogs; however, the quantity or the way the nutrients are provided may change.'
Dog-food products described as light, lite, or low calorie must meet specific calorie levels set by the Association of American Feed Control Officials (AAFCO), while dog foods named “less” or “reduced calorie” must show a percent reduction in calories as compared to a product in the same moisture-content category. The following table shows the guidelines as set by AAFCO for both dog and cat foods for determining whether a product can use the term “light.”
| Food Texture | Moisture Content | Dog Foods Maximum kcal ME/kg | Cat Foods Maximum kcalME/kg |
|---|---|---|---|
| Dry | less than 20% moisture | 3,100 | 3,250 |
| Semi-Moist | between 20 and 64% moisture | 2,500 | 2,650 |
| Canned | 65% or more moisture | 900 | 950 |
Like light versus reduced-calorie foods, lean or low-fat dog-food products must meet specific fat levels set by AAFCO, and less-fat or reduced-fat dog-food products need to show a percent reduction in fat as compared to a product in the same moisture category. AAFCO guidelines for dog and cat foods with “lean,” “low fat,” or similar words are shown in the following table.
| Food Texture | Moisture Content | Dog Foods Maximum % Crude Fat | Cat Foods Maximum % Crude Fat |
|---|---|---|---|
| Dry | less than 20% moisture | 9 | 10 |
| Semi-Moist | between 20 and 64% moisture | 7 | 8 |
| Canned | 65% or more moisture | 4 | 5 |