You have a powerful defense system that protects you against viruses, bacteria, and cancer. What is it? Your immune system, of course! Your immune system is capable of launching a coordinated attack should the need arise. The cells and proteins that make up this system are always on guard and ready to fight off invaders. These cells never have the luxury of sleeping – nor do you want them to.
As with other organs in your body, your immune system ages. The cells that once protected you become more sluggish with age. As a result, up to 30% of elderly people don’t make enough protective antibodies to a flu vaccine to offer protection against influenza. Not surprisingly, older people are more prone to infectious diseases and are more likely to die from them due to immune system aging. Other types of problems can arise as well. The risk of launching inappropriate attacks against normal tissues increases as well. When that happens, you develop an autoimmune disease or ongoing destruction of normal cells and tissues.
With your immune system playing such an important role in keeping you healthy, you want it to age as “gracefully” as possible. If you think about it, the most powerful lifestyle habit you have against generalized aging is exercise. Can exercise also slow the aging of your immune system?
What Causes Immune System Aging
Aging of the immune system is called immunosenescence. If you want to live a long time, keeping your immune system “young” will help get you there. A study showed that a healthy immune system is a feature linked with exceptional longevity. Your immune system ages in two ways. As mentioned, it becomes less effective at protecting you against foreign invaders AND it becomes more prone to mistakes, for example, attacking normal tissue. Sometimes, as you age, immune cells outstay their welcome and don’t die when they should. That’s not a good thing either. The good news is your immune system is capable of remodeling itself as you age. Can exercise help build a more youthful immune system?
Exercise and Immune System Aging
Of the types of exercise you do to maintain health and ward off the aging process, endurance exercise appears most beneficial for preserving immune health. Your immune system has two main components: the innate immune system and the adaptive immune system.
In the adaptive component of the immune system, you have a branch that consists of T-cells and another group called B-cells. It’s B-cells that can turn into antibody-producing cells. However, T-cells have important regulatory and cytotoxic functions that protect against foreign invaders. Some studies show endurance training helps preserve T-cell function as you age.
In addition, another type of cell, part of the innate immune system, are natural killer cells, or NK cells. These cells have the remarkable ability to destroy viruses and cancer cells on contact. Studies show that moderate exercise can boost the function of these protective immune cells.
Interestingly, a study carried out in cancer patients showed that when survivors exercised after completing chemotherapy, their immune systems remodeled and became more effective at fending off a future cancer recurrence. We know that exercise seems to lower the risk of some forms of cancer. Immune system remodeling could partially explain these protective effects. Researchers involved in the study believe exercise may help eliminate “bad” immune T-cells and replace them with healthier, more efficient ones.
Regular physical activity may also help tame tissue damage due to an overactive immune system. Remember, the immune system can become inappropriately active as well. We know that inflammation is the underlying cause of a number of health problems and there’s evidence that exercise helps reign in inflammation. So, exercise may help modulate immune function, keeping it at a level where it’s efficient but not so out of control that it damages cells and tissues.
One thing to be aware of. Moderate exercise appears to be beneficial for immune health, regardless of age, while exhaustive exercise has the opposite effect, it can suppress healthy function and increase the risk of colds and viruses. The effect would be enhanced if you’re skimping on sleep or under physical or mental stress. Stress and lack of sleep are both damaging to immune function.
Another time when exercise can suppress immune function is right after an intense or long duration workout. Studies show there’s a window period of between 3 and 72 hours where high-intensity exercise can suppress immune function. This mostly applies to athletes that train hard and for long periods of time as well as marathon runners after a race. Studies suggest that supplementing with carbohydrates (by drinking a sports beverage) during sessions longer than 90 minutes may improve immune function and lower the risk of illness.
A Note on Immune System Function and Diet
Despite what you read, there really are no magical immune boosting foods. However, diet quality is important for immune system health. Low levels of certain vitamins, particularly vitamins A, C, E, and D can impact immune activity. Also, reduced levels of iron, selenium, and zinc are linked, in some studies, with sluggish immune function. People who are malnourished are at higher risk of infection. This may also hold true if you eat a diet that excessively restricts calories. Make sure you’re eating a nutrient-dense diet.
The Bottom Line
It looks as if aerobic exercise may have an anti-aging effect on your immune system too. The key is to keep your training consistent and balanced and not over-train. Regular exercise may help to keep your immune system spry and that’s important for health no matter what your age.
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