The immune system is an intricate network of specialized tissues, organs, cells, and hormones. The lymph system and lymph nodes, spleen, bone marrow, and thymus gland all play a role, as do lymphocytes (specialized white blood cells), antibodies, and specialized proteins.
There are two main types of immunity; innate and acquired. Innate immunity is the body’s built in system of resisting disease including the skin, lining of the gastrointestinal tract, mucous secretions, and stomach acid.
Acquired or adaptive immunity involves the immune system’s further defenses against invaders created as the body is exposed to different pathogens through exposure, illness or vaccination. The immune system develops a memory of each disease it fights and is able to quickly recognize and defend against the pathogen the next time it appears.
Symptoms of a weakened immune system include skin infections, recurring parasitic infections, and initially mild infections or illnesses that progress into serious health issues when the body cannot build a strong enough response to defend itself. For cats, frequent upper respiratory infections are also indicative of a weak immune system.
Building a Healthy Immune System
- Diet is always the first line of defense. High quality, nutritious food is the first step in building a strong immune system. If your companion is consuming food containing inferior protein sources such as by-product meals, corn and soy, cheap fillers such as beet pulp and pea fiber, and includes any number of toxins such as chemical preservatives, food dyes, and additives; his immune system is being depleted daily just to cope with his diet. Every extra penny you spend on better quality food saves you hundreds in veterinary bills. Many people wait until their animal has a serious or chronic illness such as cancer, kidney disease or allergies to finally change their diet. Prevention is so much kinder and immeasurably more effective. Please see the article about How to Choose the Best Pet Food for more information about proper diet. Feeding a varied diet that includes as much fresh food as possible does take a bit more effort than scooping kibble out of a bag, but it is truly worth the effort in the long run.
- Healthy Digestive Tract: One of the benefits of a healthy diet is a healthy gastrointestinal tract. If the digestive tract is weakened by inflammation from allergies, inflammatory bowel disease or other digestive disorders, even the nutrients in a healthy diet are harder to process and absorb. Healing and maintaining the digestive tract is vital to overall health and immunity. Digestive enzymes, probiotics and essential fatty acids all play a role in gastrointestinal health and proper digestion.
- Exercise must also be mentioned for its role in helping build and maintain a strong immune system. Moderate exercise has been shown to improve immune factors in humans and animals. You both need the exercise – so go for a good long walk every day.
- Weight control is also key – overweight animals are much more susceptible to chronic and acute diseases and infections. Proper diet AND exercise are needed to help with weight control. (See How to Tell if Your Dog or Cat is Overweight)
- A good quality daily multi-vitamin and mineral supplement is a simple way to help bolster the immune system. I like to alternate the vitamin supplements I use for my cats and dogs to provide a more varied source of extra nutrition. For instance, I often give a regular multi-vitamin at one meal and a “greens” supplement at another meal. Please see the article Daily Supplements for a Healthy Companion for more information.
Antioxidants for a Power Boost
Antioxidants help prevent oxidation, help increase immune function, and possibly decrease the risk of infection and cancer. Antioxidants exist as vitamins, minerals and other compounds in foods. They act as scavengers, helping to prevent cell and tissue damage by destroying free radicals. Free radicals are highly reactive molecules and fragments of molecules that can damage the body at the cellular level, leaving the body susceptible to cancer, heart disease, and many other degenerative diseases.
Vitamins A, C and E are the most commonly known antioxidants. Vitamin A is found in the liver and other animal tissues. It is abundant in fish liver oils such as cod liver oil. Carotene is a precursor to vitamin A found in plant material. Dogs can convert carotene to vitamin A by way of an enzyme found in the wall of the intestine. Cats, however, do not convert carotene well and must receive adequate vitamin A from animal sources.
Vitamin A helps regulate the immune system by making white blood cells that destroy harmful bacteria and viruses. Vitamin A also helps maintain the integrity of skin and mucous membranes, which also function as a barrier to bacteria and viruses as well as protect against shedding of cells into the urinary tract which can lead to the formation of stones and cause urinary tract problems.
Vitamin C is the most abundant water-soluble antioxidant in the body and is manufactured in the liver and kidneys of dogs and cats. It is available from fresh or lightly cooked fruits and vegetables. Vitamin C is especially good at combating free-radical formation caused by pollution.
Vitamin E is the most abundant fat-soluble antioxidant in the body. It is present in many foods including vegetable oils, cereal grains, greens, liver and eggs. It is particularly helpful in protecting against oxidation, especially in fatty tissues.
Other powerful antioxidants include green tea, selenium, Co-Enzyme Q10, bioflavonoids, N-acetylcysteine, proanthocyanidins (pycnogenol) typically derived from grape seed extract or pine bark, quercetin, soy isoflavones, and zinc.
Herbs, Mushrooms and Nutraceuticals for Extra Support
Chinese Herbs are available in a variety of combinations for immune support. Astragalus is one of the more commonly found Chinese herbs in immune formulations. Selecting the proper Chinese herbal formula is not always straightforward since a variety of conditions need to be considered before deciding on the best combination, so sometimes the guidance of a trained holistic veterinarian is important.
Green tea contains polyphenols which target cancer cells for destruction and helps eliminate free radicals. It also supports the production of a protein that protects healthy cells.
Circumin, or turmeric root, has very powerful antioxidant and anti-inflammatory properties. It has a wide range of uses for both chronic and acute illnesses and is an excellent cancer preventative.
Echinacea stimulates the immune system to fight bacterial and viral infections. It is a good choice for acute conditions but is not recommended for continual long term use. Echinacea works best when given as a preventative – to help an animal avoid contracting an illness or infection they may be exposed to.
Mushrooms such as Maitake, Reishi and Shitake stimulate T-helper cells (which are integral to a strong immune response) and powerfully boost the overall immune system. Cordyseps is a Chinese mushroom with antioxidant, antiviral and cancer fighting properties.
Colostrum is the first milk produced by mothers. Most colostrum commercially available is from cows. It has many immune boosting properties including factors that support T-helper cells. It may also play a role in the metabolism of essential fatty acids. Useful for acute and chronic disease including autoimmune disorders.
Cat’s Claw (Una de gato) has anti-oxidant and immune enhancing properties as well as anti-hypertensive effects (lowers blood pressure & supports circulation). Cat’s Claw is derived from a vine found in South America. It is often used in combination with other herbs. It can be useful in treating a wide variety of illness including parasites, colitis, gastritis, leaky gut, tumors and for acute conditions such as viral and respiratory infections.
Again, prevention is the best course, but should your companion fall ill, extra support for the immune system through nutrition, herbs and supplements can give her the upper hand and aid in her speedy recovery.