How does aging affect your immune system and susceptibility to illness

As we get older, our immune system changes in ways that can make us more likely to get sick. This is because aging affects how well our body defends itself against infections and diseases.

One key change is something called **immune decline** or **immunosenescence**. This means the immune system doesn’t work as strongly as it used to. The cells that fight off germs don’t regenerate as quickly, and their ability to respond to new threats weakens over time[3]. Because of this, older adults often have a harder time fighting infections like the flu or pneumonia.

Another important factor is **chronic inflammation**, sometimes called “inflammaging.” As we age, low-level inflammation sticks around longer than it should. While some inflammation helps protect us from harm, chronic inflammation can damage tissues and organs over time[2][4]. This ongoing irritation contributes not only to infections but also increases risks for diseases such as heart disease and Alzheimer’s.

However, there’s good news: researchers have found that some people maintain what’s called **immune resilience**—the ability of the immune system to stay strong despite aging[1][3][5]. Immune resilience helps keep the immune response youthful by preserving key genes involved in regenerating immune cells. People with higher immune resilience tend to live healthier lives with fewer serious illnesses even into old age.

Studies show that boosting this resilience during midlife (around ages 40–70) can significantly reduce risks of death from infections and chronic diseases later on[3]. It also improves how well vaccines work for older adults by helping their bodies mount a better defense when vaccinated.

In summary:

– Aging slows down your immune system’s ability to fight germs.
– Chronic low-grade inflammation increases with age and harms your health.
– Immune resilience counters these effects by keeping your defenses stronger.
– Midlife is an important time to support your immunity for healthier aging.

Taking care of your health through good nutrition, exercise, stress management, and possibly medical interventions aimed at boosting immunity could help maintain this resilience. That way you’re better protected against illness even as you grow older.