Each day, you are exposed to potential threats. To counter this relentless attack, your body has developed a complex way to keep you safe — your immune system.
Many people never give a thought to their immune system. However, it’s a good idea to become more pro-active in supporting your immune health, particularly as you grow older.
What Comprises Your Immune System?
The immune system is actually a vast network of organs, tissues, and cells working together to support health.
Your immune system allows your body to identify what is foreign and what is “self.” The immune system uses unique methods to support your health.
In general, there are two subsystems of your immune system — the innate and adaptive immune systems.
The innate immune system provides speedy defense against potential issues, but works in a nonspecific manner. And while it is your dominant system for defense, it does not offer long-lasting immunity.
It does provide specific barriers for optimal immune function.
For example, your skin acts as a mechanical barrier. Tears and urine, coughing and sneezing, and mucus in your gut and respiratory tract all help support your immune system.
Chemical barriers also help. Enzymes in tears and saliva along with acids and enzymes in the stomach also serve to promote a healthy immune response.
An example of a biological barrier includes the beneficial probiotic bacteria in your gut, bacteria that should ideally outnumber and compete with unfriendly bacteria.
There are several different types of specialized innate immune cells. White blood cells called neutrophils are the most numerous innate immune cells.
Innate cells respond quickly and broadly to potential problems, and initiate the second type of immune response, called adaptive immunity.
Unlike innate responses, adaptive immune responses offer long-lasting effects. Adaptive immune responses involve white blood cells called B and T lymphocytes.
Where is Your Immune System Located?
Your immune system is dispersed throughout the body.
Skin. As you’ve seen, your skin is your first line of defense.
Bone Marrow. The bone marrow houses stems cells that can develop into different cell types. One bone marrow stem cell is a precursor to innate immune cells. Another stem cell gives rise to adaptive immune cells — the B cells and T cells.
Thymus. This tiny organ is found in the upper chest in front of the heart. T cells mature in the thymus. However, with aging, the thymus becomes less functional.
Lymphatic System. This system contains a network of vessels carrying a clear fluid called lymph as well as tissues called lymph nodes. The lymphatic system transports immune cells to around 600 lymph nodes clustered throughout the body. Lymph nodes contain white blood cells, especially lymphocytes, which support immune health.
Mucosal Tissue. Because mucosal surfaces are potential entry points, special immune hubs are located in mucosal tissues like the gastrointestinal and respiratory tracts. The gut contains 70% of the body’s immune cells and produces the majority of antibodies.
Spleen. This organ is located on the left side of the body behind the stomach. It contains many B lymphocytes to help support immune response.
Factors Affecting Immune Health
In older adults, immune cell response and the production of antibodies can change. The bone marrow of an older person can’t produce as many stem cells to develop into immune cells.
Older individuals tend to suffer more with imbalanced inflammatory response.
Nutritional issues also impact immune health. Older people tend to consume less food and have less variety in their diets, so their vitamin consumption may be less than optimal. Research shows that vitamins and minerals help support immune system function.
Psychological health also impacts immune health at any age. Moodiness and excess stress can affect immune function.
How to Enhance Immune System Function
Because the aging process and other factors impact immune function, it’s important to know how to support your immune health. Here are some simple strategies:
Avoid Smoking and Minimize Alcohol Consumption. Tobacco smoking and over-consumption of alcohol can affect immune system function.
Stay Active and Maintain Your Optimal Weight. Exercise supports antibody production and immune cell health and promotes healthy levels of stress hormones. When it comes to weight, recent Australian research found that even modest weight loss can promote immune health.
Manage Your Stress Level and Emotional Health. While short-term stress may promote immune health, long-term stress does not. Research demonstrates that immune cell activity is lowered with mood concerns and social isolation. This makes it important to engage in social relationships, learn stress-reducing techniques, and seek professional help for emotional issues.
Get Sufficient Sleep. Good sleep promotes immune response. Most health professionals recommend 7 to 9 hours of good quality sleep each night for adults of all ages. Continued sleep loss can lead to imbalanced levels of inflammation.
Look at Diet and Supplemental Nutrients. For optimal immune health, it’s good to load up on phytonutrient- and antioxidant-rich foods: dark leafy green vegetables, tomatoes, peppers, broccoli, berries, and other colorful fruits. Foods to avoid for better immune health include all processed foods, sugar, trans fats, refined vegetable oils, and white flour. Certain nutrients have been shown to bolster immunity. Dietary omega-3s, found in fatty fish or marine oil supplements, help support immune function. Probiotic supplements help support the population of “friendly” intestinal bacteria for optimal immune function. Other herbal nutrients, vitamins such as vitamin C and D3, and minerals such as zinc also help support immune health.