How To Slow Down The Aging Of Your Immune System?

The immune system is one of the most critical systems of our body. It helps protect our body against the invasion of any foreign and harmful substances like bacteria, viruses, cancer cells, and many other harmful invaders that try to enter our body and cause harm. The immune system manufactures different types of antibodies and cells that help fight against and destroy these harmful invaders. However, as you grow older, your immune system starts slowing down and may not work as well as before. At the same time, stress of any kind can further accelerate our immune system’s aging process. Here’s everything you need to know about how to slow down the aging of your immune system.  

Medical experts say that there are primarily two types of stress – physical stress and psychological stress. A new study has now shown that any kind of stress can boost the aging process of the immune system as we get older.

The new study, published in March 2022, has shown that a major stressor to the immune system as we get older is stress. Immune aging is one of the factors that explains why older adults usually benefit less from vaccines and also why they experience more severe complications when afflicted by infections like COVID-19.⁽¹⁾ The study was conducted by the Leonard Davis School of Gerontology located at the University of Southern California. The study suggested that social stress could actually accelerate the aging of the immune system.^{(2, 3)}

The fact is that this was long suspected by those experts who study the link between immunity and aging, known as immunosenescence, that as people grow older, they witness a decrease in immune protection. However, why exactly the immune system witnesses a faster decline in certain people as compared to others is not yet clearly understood. This is the main reason why the study was launched.^{(4, 5, 6)}

The immune system is responsible for producing T cells that protect and fight against foreign invaders.⁽⁷⁾ However, T cells are born in an immature state, also referred to as naive cells, and as they start to mature, they wait to be called into action. Once they get activated, they immediately latch onto a virus or other infectious substances that may be trying to harm us or infect us. Soon, T cells transform into memory T cells, which are always ready to fight the same type of infections once again if they try to attack the body. These cells can also age to become terminally differentiated T cells that can go on to have a negative effect on other cells.^{(8, 9)}

The study above found that as they age, all people start to have fewer naive cells and more differentiated T cells. It is believed that stress can accelerate this trajectory of a reduction in immature T cells.

There is no doubt that we live in a time where stress seems to come at us from all directions. From dealing with the pandemic to facing political unrest, rising gas prices, extreme weather, and a thousand other day-to-day problems, there is no end to the stress in all of our lives.

Since stress is such a generalized and overused term, experts have begun to break it down into two categories – physical and psychological. While physical stress includes everything from activity level, weight, eating habits, and even illness and physical injuries, psychological stress arises from the many challenges in life, emotional problems, discrimination, and other mental health battles.

The answer to preventing the aging of the immune system, though, does not lie in getting rid of all the stressors of life. You just need to know how to manage your stress. Stress needs to be looked at over a longer period of time, not short-term or in the moment type of stress. Too much stress over a long period of time is known to have an impact on the body’s immune response.^{(10, 11, 12)}

Interventions to help lower your stress levels and/or build up resilience and having coping mechanisms can help slow down the aging of the immune system, thus helping address the age-related health challenges. For example, if your weight or eating habits are the causes of your stress, you can change your habits and address the cause of stress.

While there is still more research needed, but primary evidence points to the fact that people who have a more aged immune system are less capable of fighting against acute infections like COVID-19 or the flu. They are also at a higher risk of cardiovascular disease and also at a higher risk of mortality.^{(13, 14)}

Even though nothing can really put a stop to the natural aging process, there are specific changes you can make to your lifestyle and eating habits that can help you remain healthy even in older age. Here are some ways in which to slow down the aging of your immune system.

1. Getting Regular Exercise

   Exercise has a profound impact on your immune system as per a recent research in the Nature Reviews Immunology journal.⁽¹⁵⁾ It is inevitable that as we age, we tend to become less active physically. However, evidence suggests that getting as much exercise as possible can help slow down or even reverse many of the effects of immunosenescence.⁽¹⁶⁾

   Your skeletal muscles produce a wide variety of proteins known as myokines. Myokines play an essential role in reducing inflammation and also preserve immune function. This is why it is necessary to maintain your muscle mass with exercise, as it protects against infections as well as conditions like heart disease and type 2 diabetes. These are conditions that are closely associated with chronic inflammation.⁽¹⁷⁾

   One study discovered that aerobic fitness in 102 healthy male participants between the ages of 18 to 61 years is inversely proportional to the number of senescent T cells present in the bloodstream. This means that a greater level of physical fitness is directly associated with less immunosenescence.⁽¹⁸⁾ In fact, the fittest male participants in the study had fewer senescent T cells and a higher number of naive T cells.

   Another study looked at the immune responses of 61 healthy male participants in the age group of 65 to 85 years to the flu vaccine.⁽¹⁹⁾ The study found that one-third of the male participants remained highly active by running or taking part in various sports. In contrast, one-third were relatively active, and the leftover one-third essentially had a sedentary lifestyle. The research team found that the intensively active and moderately active group of males produced more antibodies in response to the flu vaccine as compared to the least active participants. At the same time, the more active males also had greater serum concentrations of antibodies to several flu strains even before taking the vaccine.

   There have been many other studies that have also found similar benefits, both from long-term physical activity and also from single bouts of activity undertaken just before vaccination.

   However, it is important to keep in mind that the majority of research into the association of exercise and immunity in older adults has been done through cross-sectional studies, studies that investigate relationships between variables only at a single point in time.

   To confirm the benefits of exercise and physical activity on the immune system, more interventional studies are needed, which would follow the participants over a period of time.

2. Maintaining a Healthy Weight

   While muscles play a major role in bringing down inflammation in older adults, the presence of excess fat or adipose tissue has the opposite effect. Normal aging can often cause weight gain in many people owing to the build-up of fatty tissue around the organs and under the skin. According to a review of several studies on the aging immune system, fat tissue can significantly contribute to inflammation.⁽²⁰⁾

   It is estimated that approximately 30 percent of the pro-inflammatory cytokine called IL-6 in the blood originates from adipose tissue. This is why being obese or overweight in older age can be a major cause of chronic inflammation.^{(21, 22)}

3. Adopt Healthy Eating Habits Like The Mediterranean Diet

   While there is no direct proof to show that making dietary changes along with lifestyle changes can help slow down the rate of immunosenescence in older adults. However, a lot of indirect evidence has pointed to this fact. Research especially suggests that the kind of diet you consume determines the risk of older adults from developing sarcopenia. Sarcopenia is a condition that causes loss of muscle strength, mass, and functionality.

   Over the years, it has been established that there is a type of two-way relationship between the immune system and the skeletal muscles. As mentioned above, muscles produce anti-inflammatory myokines, but recent studies show that chronic inflammation helps accelerate muscle loss in conditions like sarcopenia.⁽²³⁾

   Taking certain dietary supplements has been shown to reduce the risk of sarcopenia, such as polyunsaturated fatty acids and vitamin D. These are believed to help because of their anti-inflammatory properties.

   A growing body of research now suggests that people who regularly consume a Mediterranean diet are far less likely to grow frail in old age, including losing muscle strength, tiring quickly, and walking slowly. The Mediterranean diet comprises of:^{(24, 25, 26)}

   • Low amounts of added sugar and red meat
   • Moderate amounts of poultry, fish, and dairy
   • Large amounts of leafy vegetables, fruits, and olive oil.

   Older studies have further linked this type of diet to a reduced risk of obesity, type 2 diabetes, cancer, and even heart disease.

   In 2018, a review of observational studies found that people who consumed a diet that closely resembled the Mediterranean diet were less likely to become frail over a four-year period.⁽²⁷⁾

   The benefits derived are believed to be the result of the anti-inflammatory properties of such a diet.

Exercising and eating a healthy diet seem to counter the effects of immune aging. It can also be that this happens because of the way these two lifestyle factors help prevent a person from gaining weight. Many studies have shown that older adults who exercise regularly and also have a healthy weight tend to have fewer senescent T cells and lower levels of pro-inflammatory cytokines in the bloodstream. However, whether or not exercise, healthy weight management, and consuming a healthy diet can help reverse the aging of your immune system remains unclear.

There is a lot of ongoing research to find answers to this question, including also looking at how stress over a lifetime may affect immunity. It is expected that once new data becomes available, it will be possible to look at the change in the percentages of different T cells over time. Studies are also exploring the impact of stress during childhood, as there is some evidence that childhood stress and adversity can impact your health as an adult. This is why it is assumed that this likely affects immune aging as well. However, until there is some confirmed evidence, those who are aging should be aware that taking the actions described here can help slow down the aging of their immune system.

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