Antioxidants: key to a healthy immune system
At birth, the puppy’s immune system is not fully developed. Rather, it matures during the first few months of life. The immune system is important for protecting puppies from disease and infection. A mature immune system is necessary for an effective response to vaccination. The immune system can be divided into two major components:
Cell-mediated Immunity: Cells (T- and B-lymphocytes and macrophages) that recognise foreign agents (antigens) and initiate a rapid defense.
Humoral Immunity: Antibodies that circulate throughout the body binding to and thereby neutralising—toxins and microorganisms.
What are antioxidants?
Antioxidants are important, naturally occurring nutrients that help maintain health by slowing the destructive aging process of cellular molecules. They can also be important in improving immune responses and vaccine recognition in dogs and cats. They can reverse decreases in immune-cell function for senior dogs and cats. A blend of several antioxidants in moderate amounts may be more effective than high levels of one antioxidant. Antioxidants are nutrients found naturally in the body and in plants such as fruits and vegetables.
Why do puppies need antioxidants?
Antioxidants, such as vitamin E, beta-carotene, and lutein, have been shown to boost both cell-mediated and humoral immune function in dogs. Lutein and beta-carotene have also been shown to optimise vaccine antigen recognition, an effect that is very important for puppies undergoing their initial vaccination series.
The study: A group of 40, six-week-old puppies were randomly allotted into two subgroups. For 120 days, puppies were fed either a control puppy diet or the same diet formulated with added vitamin E, beta-carotene, and lutein. During the study, all the puppies received their normal vaccinations. At the end of the 120-day feeding period, all the puppies were vaccinated against distemper and parvovirus, and antibody responses were measured. Following that, all the puppies received an injection of a novel antigen and the antibody responses were measured.
Findings: Compared with puppies fed the control diet, puppies fed the diet with the antioxidant combination had enhanced responses to vaccination (see chart below). There were more antibodies present following injection with a novel antigen, indicating that the immune systems of puppies fed antioxidants may be better able to respond to challenges from infectious agents. There was greater cell-mediated immune response, indicating that feeding antioxidants to puppies increases both T- and B-cell activity.
How antioxidants work?
As cells function normally in the body, they produce damaged molecules—called free radicals. These free radicals are highly unstable and steal components from other cellular molecules, such as fat, protein, or DNA, thereby spreading the damage. This damage continues in a chain reaction, and entire cells soon become damaged and die. This process is called peroxidation.
Peroxidation is useful because it helps the body destroy cells that have outlived their usefulness and kills germs and parasites. However, peroxidation, when left unchecked, also destroys or damages healthy cells. Antioxidants help prevent widespread cellular destruction by willingly donating components to stabilise free radicals. More importantly, antioxidants return to the surface of the cell to stabilise rather than damage other cellular components. When there are not enough antioxidants to hold peroxidation in check, free radicals begin damaging healthy cells, which, in turn, can lead to problems. For example, free radical damage to immune cells can lead to an increased risk of infections.
Because antioxidants play a key role in minimizing damage to cells, their addition to high-quality puppy diet can help maintain good health and protect against viruses, bacteria and parasites.
Antioxidants and aging
Recent research also examined the effect of aging on immune responses. The findings indicate that as dogs and cats age, immune cell responses may decline. Including antioxidants in the diet can reverse the age related decrease in immune cell function.
All Eukanuba and IAMS dog and cat foods and Eukanuba Veterinary Diets contain added antioxidants to help support a healthy immune system.