Endocrine System

The endocrine system consists of several glands and organs that produce hormones. Hormones act as messengers to help regulate and coordinate activities throughout the body. As people age, the levels and activity of some hormones (in addition to sex hormones) decrease. For example, the level of growth hormone decreases, causing changes in muscles such as a decrease in muscle mass. The level of aldosterone, a hormone produced by the adrenal glands, also decreases. This decrease may contribute to the tendency of older people to become dehydrated more easily.

Most hormonal changes do not affect how the body functions. However, during certain circumstances, the body's functions may be affected. For example, after eating a large meal, insulin released from the pancreas is not used as efficiently as usual. Insulin helps control the level of sugar in the blood. When insulin is used less efficiently, the level of sugar in the blood rises slightly higher than usual, and the level takes longer to return to normal. This change may have no noticeable effect. But in some people, it can be an early warning of diabetes.