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Why might older adults become more vulnerable to disease?

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primates — aging Primates are among the longest-lived groups of mammals.

Older adults become increasingly vulnerable to disease due to a combination of physiological decline and the cumulative effects of cellular damage over time.

Physiological and Cellular Decline

As individuals age, the performance of vital organs—including the heart, kidneys, and lungs—gradually declines. This is partly caused by a loss of cells and a reduction in the reserve capacities of these organs. Furthermore, remaining cells may function less efficiently, with reduced enzymatic activity slowing down essential chemical reactions.1

Immune System Changes

A primary factor in increased vulnerability is the decline of the immune system, particularly after age 60 or 70. The systems responsible for defending the body against infectious agents wear down, leaving individuals more susceptible to infection. Additionally, age-related changes can lead to autoimmune diseases, where the immune system mistakenly attacks healthy body tissue.23

Oxidative Stress and Inflammation

Accumulated oxidative damage from reactive oxygen species impairs cellular function and contributes to chronic inflammation. This inflammatory cascade is linked to numerous age-associated pathologies, such as cancer, cardiovascular disease, and neurodegenerative conditions.4