MODULE SUPPLEMENT: IMMUNE SYSTEM
What Happens with Age?

In general, the older adult can be considered to be in a state of immune dysregulation. Changes occur in different components of the immune system which alter its ability to function effectively and efficiently.

To understand the changes that occur with age, some basic background about immunity is needed. This review greatly simplifies the immune response, especially since our knowledge of its various components is expanding exponentially. However, it will facilitate an understanding of why older adults are vulnerable to many health related problems.

There are two main components of the immune system:

• The non-specific or innate.
  
  
• The specific or acquired. Acquired immunity can be obtained passively (through Mother's milk or immunoglobulin) or actively (through getting a disease or an immunization).

However, it is important to realize that these two components are intimately inter-related, a point to which we will return.